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BEGIN:VEVENT
SUMMARY:Jishnu Ray (University of British Columbia)
DTSTART:20200423T210000Z
DTEND:20200423T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/1
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/1/"
 >Conjectures in Iwasawa Theory of Selmer groups and Iwasawa Algebras</a>\n
 by Jishnu Ray (University of British Columbia) as part of UCSD number theo
 ry seminar\n\n\nAbstract\nThe Iwasawa Theory of Selmer groups provides a n
 atural way for p-adic approach to the celebrated Birch and Swinnerton Dyer
  conjecture. Over a non-commutative p-adic Lie extension\, the (dual) Selm
 er group becomes a module over a non-commutative Iwasawa algebra and its s
 tructure can be understood by analyzing “(left) reflexive ideals” in t
 he Iwasawa algebra. In this talk\, we will start by recalling several exis
 ting conjectures in Iwasawa Theory and then we will give an explicit ring-
 theoretic presentation\, by generators and relations\, of such Iwasawa alg
 ebras and sketch its implications in understanding the (two-sides) reflexi
 ve ideals. Generalizing Clozel’s work for SL(2)\, we will also show that
  such an explicit presentation of Iwasawa algebras can be obtained for a m
 uch wider class of p-adic Lie groups viz. uniform pro-p groups and the pro
 -p Iwahori of GL(n\,Z_p). Further\, if time permits\, I will also sketch s
 ome of my recent Iwasawa theoretic results joint with Sujatha Ramdorai.\n\
 npretalk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jize Yu (California Institute of Technology)
DTSTART:20200430T210000Z
DTEND:20200430T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/2
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/2/"
 >The integral geometric Satake equivalence in mixed characteristic</a>\nby
  Jize Yu (California Institute of Technology) as part of UCSD number theor
 y seminar\n\nLecture held in APM 7321.\n\nAbstract\nThe geometric Satake e
 quivalence establishes a link between two monoidal categories: the categor
 y of perverse sheaves on the local Hecke stack and the category of finitel
 y generated representations of the Langlands dual group. It has many impor
 tant applications in the study of the geometric Langlands program and numb
 er theory. In this talk\, I will discuss the integral coefficient geometri
 c Satake equivalence in the mixed characteristic setting. It generalizes t
 he previous results of Lusztig\, Ginzburg\, Mirkovic-Vilonen\, and Zhu. Ti
 me permitting\, I will discuss an application of this result in constructi
 ng a Jacquet-Langlands transfer.\n\nThere will be a pretalk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Carl Wang-Erickson (University of Pittsburgh)
DTSTART:20200507T210000Z
DTEND:20200507T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/3
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/3/"
 >The Eisenstein ideal with squarefree level</a>\nby Carl Wang-Erickson (Un
 iversity of Pittsburgh) as part of UCSD number theory seminar\n\nLecture h
 eld in APM 7321.\n\nAbstract\nIn his landmark paper "Modular forms and the
  Eisenstein ideal\," Mazur studied congruences modulo a prime p between th
 e Hecke eigenvalues of an Eisenstein series and the Hecke eigenvalues of c
 usp forms\, assuming these modular forms have weight 2 and prime level N. 
 He asked about generalizations to squarefree levels N. I will present some
  work on such generalizations\, which is joint with Preston Wake and Cathe
 rine Hsu.\n\nThere will be a pretalk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jack Thorne (Cambridge University)
DTSTART:20200521T210000Z
DTEND:20200521T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/5
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/5/"
 >Symmetric power functoriality for holomorphic modular forms</a>\nby Jack 
 Thorne (Cambridge University) as part of UCSD number theory seminar\n\nLec
 ture held in APM 7321.\n\nAbstract\nLanglands’s functoriality conjecture
 s predict the existence of “liftings” of automorphic representations a
 long morphisms of L-groups. A basic case of interest comes from the irredu
 cible algebraic representations of GL(2)\, thought of as the L-group of th
 e reductive group GL(2) over Q. I will discuss the proof\, joint with Jame
 s Newton\,  of the existence of the corresponding functorial liftings for 
 a broad class of holomorphic modular forms\, including Ramanujan’s Delta
  function.\n\nThere will be a pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Elena Fuchs (University of California\, Davis)
DTSTART:20200528T210000Z
DTEND:20200528T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/6
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/6/"
 >Prime components in integral circle packings</a>\nby Elena Fuchs (Univers
 ity of California\, Davis) as part of UCSD number theory seminar\n\nLectur
 e held in APM 7321.\n\nAbstract\nCircle packings in which all circles have
  integer curvature\, particularly Apollonian circle packings\, have in the
  last decade become objects of great interest in number theory. In this ta
 lk\, we explore some of their most fascinating arithmetic features\, from 
 local to global properties to prime components in the packings\, going fro
 m theorems\, to widely believed conjectures\, to wild guesses as to what m
 ight be true.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Niccolo Ronchetti (University of California\, Los Angeles)
DTSTART:20200604T210000Z
DTEND:20200604T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/7
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/7/"
 >A derived Hecke action on the ordinary Hida tower</a>\nby Niccolo Ronchet
 ti (University of California\, Los Angeles) as part of UCSD number theory 
 seminar\n\nLecture held in APM 7321.\n\nAbstract\nWhen studying the cohomo
 logy of Shimura varieties and arithmetic manifolds\, one encounters the fo
 llowing phenomenon: the same Hecke eigensystem shows up in multiple degree
 s around the middle dimension\, and its multiplicities in these degrees re
 sembles that of an exterior algebra.\n\nIn a series of recent papers\, Ven
 katesh and his collaborators provide an explanation: they construct graded
  objects having a graded action on the cohomology\, and show that under go
 od circumstances this action factors through that of an explicit exterior 
 algebra\, which in turn acts faithfully and generate the entire Hecke eige
 nspace.\n\nIn this talk\, we discuss joint work with Khare where we invest
 igate the $p=p$ situation (as opposed to the $l \\neq p$ situation\, which
  is the main object of study of Venkatesh’s Derived Hecke Algebra paper)
 : we construct a degree-raising action on the cohomology of the ordinary H
 ida tower and show that (under some technical assumptions)\, this action g
 enerates the full Hecke eigenspace under its lowest nonzero degree. Then\,
  we bring Galois representations into the picture\, and show that the deri
 ved Hecke action constructed before is in fact related to the action of a 
 certain dual Selmer group.\n\nThere will be a pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Federico Pellarin (U. Jean Monnet\, Saint-Etienne\, France)
DTSTART:20200514T170000Z
DTEND:20200514T180000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/8
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/8/"
 >On Drinfeld modular forms in Tate algebras</a>\nby Federico Pellarin (U. 
 Jean Monnet\, Saint-Etienne\, France) as part of UCSD number theory semina
 r\n\nLecture held in APM 7321.\n\nAbstract\nIn this talk we will describe 
 some recent works on Drinfeld modular forms with values in Tate algebras (
 in 'equal positive characteristic'). In particular\, we will discuss some 
 remarkable identities (proved or conjectural) for Eisenstein and Poincaré
  series\, and the problem of analytically interpolate families of Drinfeld
  modular forms for congruence subgroups at the infinity place.\n\nThe pre-
 talk will begin 30 minutes prior (09:30 local time).\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xin Tong (University of California\, San Diego)
DTSTART:20200514T210000Z
DTEND:20200514T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/10
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/10/
 ">Towards a Hodge-Iwasawa theory</a>\nby Xin Tong (University of Californi
 a\, San Diego) as part of UCSD number theory seminar\n\n\nAbstract\nWith t
 he motivation of generalizing the corresponding geometrization of Tamagawa
 -Iwasawa theory after Kedlaya-Pottharst\, and with motivation of establish
 ing the corresponding equivariant version of the relative p-adic Hodge the
 ory after Kedlaya-Liu aiming at the deformation of representations of prof
 inite fundamental groups and the family of étale local systems\, we initi
 ate the corresponding Hodge-Iwasawa theory with deep point of view and phi
 losophy in mind from early work of Kato and Fukaya-Kato. In this talk\, we
  are going to discuss some foundational results on the Hodge-Iwasawa modul
 es and Hodge-Iwasawa sheaves\, as well as some interesting investigation t
 owards the goal in our mind\, which are taken from our first paper in this
  series project.\n\nThere will be a pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting (UCSD)
DTSTART:20201001T210000Z
DTEND:20201001T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/11
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/11/
 ">Organizational meeting</a>\nby Organizational meeting (UCSD) as part of 
 UCSD number theory seminar\n\nLecture held in normally APM 7321\, currentl
 y online.\n\nAbstract\nThis is an organizational meeting for the remainder
  of the term. The seminar itself will begin one week later.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aaron Pollack (UCSD)
DTSTART:20201008T210000Z
DTEND:20201008T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/12
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/12/
 ">Singular modular forms on quaternionic E_8</a>\nby Aaron Pollack (UCSD) 
 as part of UCSD number theory seminar\n\nLecture held in normally APM 7321
 \, currently online.\n\nAbstract\nThe exceptional group $E_{7\,3}$ has a s
 ymmetric space with Hermitian tube structure.  On it\, Henry Kim wrote dow
 n low weight holomorphic modular forms that are "singular" in the sense th
 at their Fourier expansion has many terms equal to zero.  The symmetric sp
 ace associated to the exceptional group $E_{8\,4}$ does not have a Hermiti
 an structure\, but it has what might be the next best thing: a quaternioni
 c structure and associated "modular forms". I will explain the constructio
 n of singular modular forms on $E_{8\,4}$\, and the proof that these speci
 al modular forms have rational Fourier expansions\, in a precise sense.  T
 his builds off of work of Wee Teck Gan and uses key input from Gordan Savi
 n.\n\npre-talk at 1:30pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Samuel Mundy (Columbia)
DTSTART:20201105T220000Z
DTEND:20201105T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/13
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/13/
 ">Archimedean components of Eisenstein series and CAP forms for $G_2$</a>\
 nby Samuel Mundy (Columbia) as part of UCSD number theory seminar\n\nLectu
 re held in normally APM 7321\, currently online.\n\nAbstract\nI will talk 
 about some recent work determining the archimedean components of certain E
 isenstein series and CAP forms induced from the long root parabolic of $G_
 2$. I will also discuss how these results are being used in some work in p
 rogress on producing nonzero classes in symmetric cube Selmer groups.\n\np
 re-talk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brandon Alberts (UCSD)
DTSTART:20201029T210000Z
DTEND:20201029T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/14
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/14/
 ">Modeling Malle's Conjecture with Random Groups</a>\nby Brandon Alberts (
 UCSD) as part of UCSD number theory seminar\n\nLecture held in normally AP
 M 7321\, currently online.\n\nAbstract\nWe construct a random group with a
  local structure that models the behavior of the absolute Galois group ${\
 \rm Gal}(\\overline{K}/K)$\, and prove that this random group satisfies Ma
 lle's conjecture for counting number fields ordered by discriminant with p
 robability 1. This work is motivated by the use of random groups to model 
 class group statistics in families of number fields (and generalizations).
  We take care to address the known counter-examples to Malle's conjecture 
 and how these may be incorporated into the random group.\n\npre-talk at 1:
 30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:James Upton (UCSD)
DTSTART:20201112T220000Z
DTEND:20201112T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/15
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/15/
 ">Newton Slopes in $\\mathbb{Z}_p$-Towers of Curves</a>\nby James Upton (U
 CSD) as part of UCSD number theory seminar\n\nLecture held in normally APM
  7321\, currently online.\n\nAbstract\nLet $X/\\mathbb{F}_q$ be a smooth a
 ffine curve over a finite field of characteristic $p > 2$. In this talk we
  discuss the $p$-adic variation of zeta functions $Z(X_n\,s)$ in a pro-cov
 ering $X_\\infty:\\cdots \\to X_1 \\to X_0 = X$ with total Galois group $\
 \mathbb{Z}_p$. For certain ``monodromy stable'' coverings over an ordinary
  curve $X$\, we prove that the $q$-adic Newton slopes of $Z(X_n\,s)/Z(X\,s
 )$ approach a uniform distribution in the interval $[0\,1]$\, confirming a
  conjecture of Daqing Wan. We also prove a ``Riemann hypothesis'' for a fa
 mily of Galois representations associated to $X_\\infty/X$\, analogous to 
 the Riemann hypothesis for equicharacteristic  $L$-series as posed by Davi
 d Goss. This is joint work with Joe Kramer-Miller.\n\npre-talk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yifeng Liu (Yale University)
DTSTART:20201120T000000Z
DTEND:20201120T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/16
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/16/
 ">Beilinson-Bloch conjecture and arithmetic inner product formula</a>\nby 
 Yifeng Liu (Yale University) as part of UCSD number theory seminar\n\nLect
 ure held in normally APM 7321\, currently online.\n\nAbstract\nIn this tal
 k\, we study the Chow group of the motive associated to a tempered global 
 L-packet \\pi of unitary groups of even rank with respect to a CM extensio
 n\, whose global root number is -1. We show that\, under some restrictions
  on the ramification of \\pi\, if the central derivative L'(1/2\,\\pi) is 
 nonvanishing\, then the \\pi-nearly isotypic localization of the Chow grou
 p of a certain unitary Shimura variety over its reflex field does not vani
 sh. This proves part of the Beilinson--Bloch conjecture for Chow groups an
 d L-functions. Moreover\, assuming the modularity of Kudla's generating fu
 nctions of special cycles\, we explicitly construct elements in a certain 
 \\pi-nearly isotypic subspace of the Chow group by arithmetic theta liftin
 g\, and compute their heights in terms of the central derivative L'(1/2\,\
 \pi) and local doubling zeta integrals. This is a joint work with Chao Li.
 \n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maxim Mornev (ETHZ)
DTSTART:20201203T180000Z
DTEND:20201203T190000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/17
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/17/
 ">Local monodromy of Drinfeld modules</a>\nby Maxim Mornev (ETHZ) as part 
 of UCSD number theory seminar\n\nLecture held in normally APM 7321\, curre
 ntly online.\n\nAbstract\nThe theory of Drinfeld modules is remarkably sim
 ilar to the theory of abelian varieties\, but their local monodromy behave
 s differently and is poorly understood. In this talk I will present a rese
 arch program which aims to fully describe this monodromy. The cornerstone 
 of this program is a "z-adic" variant of Grothendieck's l-adic monodromy t
 heorem.\n\nThe talk is aimed at a general audience of number theorists and
  arithmetic geometers. No special knowledge of monodromy theory or Drinfel
 d modules is assumed.\n\nThere will be a pre-talk introducing the theory o
 f t-motives.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Cristian Popescu (UCSD)
DTSTART:20201015T210000Z
DTEND:20201015T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/18
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/18/
 ">An equivariant Tamagawa number formula for Drinfeld modules and beyond</
 a>\nby Cristian Popescu (UCSD) as part of UCSD number theory seminar\n\nLe
 cture held in normally APM 7321\, currently online.\n\nAbstract\nI will pr
 esent a vast generalization of Taelman's 2012 celebrated class-number form
 ula for Drinfeld modules to the setting of (rigid analytic) L-functions of
  Drinfeld module motives with Galois equivariant coefficients. I will disc
 uss applications and potential extensions of this formula to the category 
 of t-modules and t-motives. This is based on joint work with Ferrara\, Gre
 en and Higgins\, and a result of meetings in the UCSD Drinfeld Module Semi
 nar.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paul Van Koughnett (Purdue)
DTSTART:20201022T210000Z
DTEND:20201022T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/19
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/19/
 ">Topological modular forms for number theorists</a>\nby Paul Van Koughnet
 t (Purdue) as part of UCSD number theory seminar\n\nLecture held in normal
 ly APM 7321\, currently online.\n\nAbstract\nThis will be a mainly exposit
 ory talk about some recent applications of number theory to topology. The 
 crux of these applications is the construction of a cohomology theory call
 ed topological modular forms (TMF) out of the moduli of elliptic curves. I
 'll explain what TMF is\, what we have been doing with it\, and what we'd 
 still like to know\; I'll also discuss more recent attempts to extend the 
 theory using level structures\, higher-dimensional abelian varieties\, and
  K3 surfaces. Time permitting\, I'll talk about my work with Dominic Culve
 r on some partial number-theoretic interpretations of TMF co-operations.\n
 \nI'll give a pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bao Le Hung (Northwestern University)
DTSTART:20201210T220000Z
DTEND:20201210T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/20
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/20/
 ">Moduli of Fontaine-Laffaille modules and mod p local-global compatibilit
 y.</a>\nby Bao Le Hung (Northwestern University) as part of UCSD number th
 eory seminar\n\nLecture held in normally APM 7321\, currently online.\n\nA
 bstract\nThe mod p cohomology of locally symmetric spaces for definite uni
 tary groups at infinite level is expected to realize the mod p local Langl
 ands correspondence for GL_n. In particular\, one expects the (component a
 t p) of the associated Galois representation to be determined by cohomolog
 y as a smooth representation. I will describe how one can establish this e
 xpectation in many cases when the local Galois representation is Fontaine-
 Laffaille.\nThis is joint work with D. Le\, S. Morra\, C. Park and Z. Qian
 .\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joshua Lam (Harvard University)
DTSTART:20210107T220000Z
DTEND:20210107T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/21
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/21/
 ">Calabi-Yau varieties and Shimura varieties</a>\nby Joshua Lam (Harvard U
 niversity) as part of UCSD number theory seminar\n\nLecture held in normal
 ly APM 7321\, currently online.\n\nAbstract\nI will discuss the Attractor 
 Conjecture for Calabi-Yau varieties\, which was formulated by Moore in the
  nineties\, highlighting the difference between Calabi-Yau varieties with 
 and without Shimura moduli. In the Shimura case\, I show that the conjectu
 re holds and gives rise to an explicit parametrization of CM points on cer
 tain Shimura varieties\; in the case without Shimura moduli\, I’ll prese
 nt counterexamples to the conjecture using unlikely intersection theory. P
 art of this is joint work with Arnav Tripathy.\n\nThere will be a 30 minut
 e pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aranya Lahiri (Indiana University)
DTSTART:20210114T220000Z
DTEND:20210114T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/22
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/22/
 ">Resolutions of locally analytic principal series representations of GL_2
 (F)</a>\nby Aranya Lahiri (Indiana University) as part of UCSD number theo
 ry seminar\n\nLecture held in normally APM 7321\, currently online.\n\nAbs
 tract\nLocally analytic representations of $p$-adic analytic groups have p
 layed a crucial role in many areas of arithmetic and representation theory
   (including in $p$-adic local Langlands program) since their introduction
  by Schneider and Teitelbaum. In this talk we will briefly review some asp
 ects of the theory of locally analytic representations.  Then\, for a loca
 lly analytic representation $V$ of $GL_2(F)$ we will construct a coefficie
 nt system attached to the Bruhat-Tits tree of $Gl_2(F)$. Finally we will u
 se this coefficient system to construct a resolution for locally analytic 
 principal series of $GL_2(F)$.\n\npre-talk at 1:30. I will discuss basics 
 and some key examples of locally analytic representations in the pre-talk.
 \n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Naomi Sweeting (Harvard University)
DTSTART:20210204T220000Z
DTEND:20210204T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/23
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/23/
 ">Kolyvagin's conjecture and higher congruences of modular forms</a>\nby N
 aomi Sweeting (Harvard University) as part of UCSD number theory seminar\n
 \nLecture held in normally APM 7321\, currently online.\n\nAbstract\nGiven
  an elliptic curve E\,  Kolyvagin used CM points on modular curves to cons
 truct a system of classes valued in the Galois cohomology of the torsion p
 oints of E.  Under the conjecture that not all of these classes vanish\, h
 e gave a description for the Selmer group of E.  This talk will report on 
 recent work proving new cases of Kolyvagin's conjecture.  The methods foll
 ow in the footsteps of Wei Zhang\, who used congruences between modular fo
 rms to prove Kolyvagin's conjecture under some technical hypotheses. We re
 move many of these hypotheses by considering congruences modulo  higher po
 wers of p.  The talk will explain the difficulties associated with higher 
 congruences of modular forms and how they can be overcome. I will also pro
 vide an introduction to the conjecture and its consequences\, including a 
 'converse theorem': algebraic rank one implies analytic rank one.\n\npre-t
 alk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kwun Angus Chung (University of Michigan)
DTSTART:20210121T220000Z
DTEND:20210121T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/24
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/24/
 ">$v$-adic convergence for exp and log in function fields and applications
  to $v$-adic $L$-values</a>\nby Kwun Angus Chung (University of Michigan) 
 as part of UCSD number theory seminar\n\nLecture held in normally APM 7321
 \, currently online.\n\nAbstract\nClassically over the rational numbers\, 
 the exponential and logarithm series converge $p$-adically within some ope
 n disc of $\\mathbb{C}_p$. For function fields\, exponential and logarithm
  series arise naturally from Drinfeld modules\, which are objects construc
 ted by Drinfeld in his thesis to prove the Langlands conjecture for $\\mat
 hrm{GL}_2$ over function fields. For a "finite place" $v$ on such a curve\
 , one can ask if the exp and log possess similar $v$-adic convergence prop
 erties. For the most basic case\, namely that of the Carlitz module over $
 \\mathbb{F}_q[T]$\, this question has been long understood. In this talk\,
  we will show the $v$-adic convergence for Drinfeld-(Hayes) modules on ell
 iptic curves and a certain class of hyperelliptic curves. As an applicatio
 n\, we are then able to obtain a formula for the $v$-adic $L$-value $L_v(1
 \,\\Psi)$ for characters in these cases\, analogous to Leopoldt's formula 
 in the number field case.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ashwin Iyengar (King's College\, London)
DTSTART:20210128T220000Z
DTEND:20210128T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/25
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/25/
 ">The Iwasawa Main Conjecture over the Extended Eigencurve</a>\nby Ashwin 
 Iyengar (King's College\, London) as part of UCSD number theory seminar\n\
 nLecture held in normally APM 7321\, currently online.\n\nAbstract\nI will
  give a brief historical motivation for the Iwasawa main conjecture\, and 
 then I will talk about a construction of a $p$-adic $L$-function in famili
 es over the extended eigencurve\, and how to formulate a two-variable Iwas
 awa main conjecture. If time permits\, I will state some open questions ab
 out this family of functions.\n\nI will give a pre-talk beforehand at 1:30
 .\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Allechar Serrano Lopez (University of Utah)
DTSTART:20210211T220000Z
DTEND:20210211T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/26
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/26/
 ">Counting elliptic curves with prescribed torsion over imaginary quadrati
 c fields</a>\nby Allechar Serrano Lopez (University of Utah) as part of UC
 SD number theory seminar\n\nLecture held in normally APM 7321\, currently 
 online.\n\nAbstract\nA generalization of Mazur's theorem states that there
  are 26 possibilities for the torsion subgroup of an elliptic curve over a
  quadratic extension of $\\mathbb{Q}$. If $G$ is one of these groups\, we 
 count the number of elliptic curves of bounded naive height whose torsion 
 subgroup is isomorphic to $G$ in the case of imaginary quadratic fields.\n
 \npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zuhair Mullath (University of Massachusetts\, Amherst)
DTSTART:20210218T220000Z
DTEND:20210218T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/27
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/27/
 ">Unobstructed Galois deformation problems associated to GSp(4)</a>\nby Zu
 hair Mullath (University of Massachusetts\, Amherst) as part of UCSD numbe
 r theory seminar\n\nLecture held in normally APM 7321\, currently online.\
 n\nAbstract\nTo a cuspidal automorphic representation of GSp(4) over $\\ma
 thbb Q$\, one can associate a compatible system of Galois representations 
 $\\{\\rho_p\\}_{p \\\; \\mathrm{prime}}$. For $p$ sufficiently large\, the
  deformation theory of the mod-$p$ reduction $\\overline \\rho_p$ is expec
 ted to be unobstructed -- meaning the universal deformation ring is a powe
 r series ring. The global obstructions to deforming $\\overline \\rho_p$ i
 s controlled by certain adjoint Bloch-Kato Selmer groups\, which are expec
 ted to be trivial for $p$ large enough.\n\nI will talk about some recent r
 esults showing that there are no local obstructions to the deformation the
 ory of $\\overline \\rho_p$ for almost all $p$. This is joint work with M.
  Broshi\, C. Sorensen\, and T. Weston.\n\nPre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tim Trudgian (UNSW Canberra at ADFA)
DTSTART:20210225T220000Z
DTEND:20210225T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/28
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/28/
 ">Verifying the Riemann hypothesis to a new height</a>\nby Tim Trudgian (U
 NSW Canberra at ADFA) as part of UCSD number theory seminar\n\nLecture hel
 d in normally APM 7321\, currently online.\n\nAbstract\nSadly\, I won’t 
 have time to prove the Riemann hypothesis in this talk. However\, I do hop
 e to outline recent work in a record partial-verification of RH. This is j
 oint work with Dave Platt\, in Bristol\, UK.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Soumya Sankar (The Ohio State University)
DTSTART:20210304T220000Z
DTEND:20210304T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/29
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/29/
 ">Counting elliptic curves with a rational $N$-isogeny</a>\nby Soumya Sank
 ar (The Ohio State University) as part of UCSD number theory seminar\n\nLe
 cture held in normally APM 7321\, currently online.\n\nAbstract\nThe class
 ical problem of counting elliptic curves with a rational N-isogeny can be 
 phrased in terms of counting rational points on certain moduli stacks of e
 lliptic curves. Counting points on stacks poses various challenges\, and I
  will discuss these along with a few ways to overcome them. I will also ta
 lk about the theory of heights on stacks developed in recent work of Ellen
 berg\, Satriano and Zureick-Brown and use it to count elliptic curves with
  an $N$-isogeny for certain $N$. The talk assumes no prior knowledge of st
 acks and is based on joint work with Brandon Boggess.\n\nThere will be a 3
 0 minute pre-talk for graduate students and postdocs preceding the main ta
 lk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting (UCSD)
DTSTART:20210311T220000Z
DTEND:20210311T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/30
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/30/
 ">Organizational meeting</a>\nby Organizational meeting (UCSD) as part of 
 UCSD number theory seminar\n\nLecture held in normally APM 7321\, currentl
 y online.\n\nAbstract\nOrganizational meeting to plan for next quarter. No
  talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Peter Koymans (MPIM)
DTSTART:20210401T180000Z
DTEND:20210401T190000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/31
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/31/
 ">Malle's conjecture for nonic Heisenberg extensions</a>\nby Peter Koymans
  (MPIM) as part of UCSD number theory seminar\n\nLecture held in normally 
 APM 7321\, currently online.\n\nAbstract\nIn 2002 Malle conjectured an asy
 mptotic formula for the number of $G$-extensions of a number field $K$ wit
 h discriminant bounded by $X$. In this talk I will discuss recent joint wo
 rk with Etienne Fouvry on this conjecture. Our main result proves Malle's 
 conjecture in the special case of nonic Heisenberg extensions.\n\npre-talk
 \n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mahesh Kakde (IISc\, Bangalore)
DTSTART:20210408T170000Z
DTEND:20210408T180000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/32
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/32/
 ">On the Brumer-Stark conjecture and applications to Hilbert's 12th proble
 m</a>\nby Mahesh Kakde (IISc\, Bangalore) as part of UCSD number theory se
 minar\n\nLecture held in normally APM 7321\, currently online.\n\nAbstract
 \nI will report on my joint work with Samit Dasgupta on the Brumer-Stark c
 onjecture proving existence of the Brumer-Stark units and on a conjecture 
 of Dasgupta giving a p-adic analytic formula for these units. I will prese
 nt a sketch of our proof of the Brumer-Stark conjecture and also mention a
 pplications to Hilbert's 12th problem\, or explicit class field theory.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lance Miller (University of Arkansas)
DTSTART:20210415T210000Z
DTEND:20210415T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/33
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/33/
 ">Finiteness of quasi-canonical lifts of elliptic curves</a>\nby Lance Mil
 ler (University of Arkansas) as part of UCSD number theory seminar\n\nLect
 ure held in normally APM 7321\, currently online.\n\nAbstract\nFix a prime
  integer $p$. Set $R$ the completed valuation ring of the maximal unramifi
 ed extension of $\\mathbb{Q}_p$. For  $X := X_1(N)$ the modular curve with
  $N$ at least 4 and coprime to $p$\, Buium-Poonen in 2009 showed that the 
 locus of canonical lifts enjoys finite intersection with preimages of fini
 te rank subgroups of $E(R)$ when $E$ is an elliptic curve with a surjectio
 n from $X$. This is done using Buium's theory of arithmetic ODEs\, in part
 icular interesting homomorphisms $E(R) \\to R$ which are arithmetic analog
 ues of Manin maps. \n\nIn this talk\, I will review the general idea behin
 d this result and other applications of arithmetic jet spaces to Diophanti
 ne geometry and discuss a recent analogous result for quasi-canonical lift
 s\, i.e.\, those curves with Serre-Tate parameter a root of unity. Here th
 e ODE Manin maps are insufficient\, so we introduce a PDE version of Buium
 's theory to provide the needed maps. All of this is joint work with A. Bu
 ium.\n\npre-talk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Owen Barrett (University of Chicago)
DTSTART:20210422T210000Z
DTEND:20210422T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/34
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/34/
 ">The derived category of the abelian category of constructible sheaves</a
 >\nby Owen Barrett (University of Chicago) as part of UCSD number theory s
 eminar\n\nLecture held in normally APM 7321\, currently online.\n\nAbstrac
 t\nNori proved in 2002 that given a complex algebraic variety $X$\, the bo
 unded\nderived category of the abelian category of constructible sheaves o
 n $X$ is\nequivalent to the usual triangulated category $D(X)$ of bounded\
 nconstructible complexes on $X$.\nHe moreover showed that given any constr
 uctible sheaf $\\mathcal F$ on\n$\\A^n$\, there is an injection $\\mathcal
  F\\hookrightarrow\\mathcal G$ with\n$\\mathcal G$ constructible and $H^i(
 \\A^n\,\\mathcal G)=0$ for $i>0$.\n\nIn this talk\, I'll discuss how to ex
 tend Nori's theorem to the case of a\nvariety over an algebraically closed
  field of positive characteristic\, with\nBetti constructible sheaves repl
 aced by $\\ell$-adic sheaves.\nThis is the case $p=0$ of the general probl
 em which asks whether the bounded\nderived category of $p$-perverse sheave
 s is equivalent to $D(X)$\, resolved\naffirmatively for the middle pervers
 ity by Beilinson.\n\npre-talk at 1:30pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/34/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Klevdal (University of Utah)
DTSTART:20210429T210000Z
DTEND:20210429T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/35
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/35/
 ">Integrality of G-local systems</a>\nby Christian Klevdal (University of 
 Utah) as part of UCSD number theory seminar\n\nLecture held in normally AP
 M 7321\, currently online.\n\nAbstract\nSimpson conjectured that for a red
 uctive group $G$\, rigid $G$-local systems on a smooth projective complex 
 variety are integral. I will discuss a proof of integrality for cohomologi
 cally rigid $G$-local systems. This generalizes and is inspired by work of
  Esnault and Groechenig for $GL_n$. Surprisingly\, the main tools used in 
 the proof (for general $G$ and $GL_n$) are the work of L. Lafforgue on the
  Langlands program for curves over function fields\, and work of Drinfeld 
 on companions of $\\ell$-adic sheaves. The major differences between gener
 al $G$ and $GL_n$ are first to make sense of companions for $G$-local syst
 ems\, and second to show that the monodromy group of a rigid G-local syste
 m is semisimple. All work is joint with Stefan Patrikis.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/35/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maria Fox (University of Oregon)
DTSTART:20210506T210000Z
DTEND:20210506T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/36
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/36/
 ">Supersingular Loci of Some Unitary Shimura Varieties</a>\nby Maria Fox (
 University of Oregon) as part of UCSD number theory seminar\n\nLecture hel
 d in normally APM 7321\, currently online.\n\nAbstract\nUnitary Shimura va
 rieties are moduli spaces of abelian varieties with an action of a quadrat
 ic imaginary field\, and extra structure. In this talk\, we'll discuss spe
 cific examples of unitary Shimura varieties whose supersingular loci can b
 e concretely described in terms of Deligne-Lusztig varieties. By Rapoport-
 Zink uniformization\, much of the structure of these supersingular loci ca
 n be understood by studying an associated moduli space of p-divisible grou
 ps (a Rapoport-Zink space). We'll discuss the geometric structure of these
  associated Rapoport-Zink spaces as well as some techniques for studying t
 hem.\n\nThere will be a pre-talk!\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/36/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sean Howe (University of Utah)
DTSTART:20210513T210000Z
DTEND:20210513T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/37
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/37/
 ">Bialgebraicity in local Shimura varieties</a>\nby Sean Howe (University 
 of Utah) as part of UCSD number theory seminar\n\nLecture held in normally
  APM 7321\, currently online.\n\nAbstract\nA classical transcendence resul
 t of Schneider on the modular $j$-invariant states that\, for $\\tau \\in 
 \\mathbb{H}$\, both $\\tau$ and $j(\\tau)$ are in $\\overline{\\mathbb{Q}}
 $ if and only if $\\tau$ is contained in an imaginary quadratic extension 
 of $\\mathbb{Q}$. The space $\\mathbb{H}$ has a natural interpretation as 
 a parameter space for $\\mathbb{Q}$-Hodge structures (or\, in this case\, 
 elliptic curves)\, and from this perspective the imaginary quadratic point
 s are distinguished as corresponding to objects with maximal symmetry. Thi
 s result has been generalized by Cohen and Shiga-Wolfart to more general m
 oduli of Hodge structures (corresponding to abelian-type Shimura varieties
 )\, and by Ullmo-Yafaev to higher dimensional loci of extra symmetry (spec
 ial subvarieties)\, where bialgebraicity is intimately connected with the 
 Pila-Zannier approach to the Andre-Oort conjecture.\n\nIn this talk\, I wi
 ll discuss work in progress with Christian Klevdal on an analogous bialgeb
 raicity characterization of special subvarieties in Scholze's local Shimur
 a varieties and more general diamond moduli of $p$-adic Hodge structures.\
 n\nThere will be a pretalk!\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/37/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nahid Walji (University of British Columbia)
DTSTART:20210520T210000Z
DTEND:20210520T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/38
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/38/
 ">On the conjectural decomposition of symmetric powers of automorphic repr
 esentations for GL(3) and GL(4)</a>\nby Nahid Walji (University of British
  Columbia) as part of UCSD number theory seminar\n\nLecture held in normal
 ly APM 7321\, currently online.\n\nAbstract\nLet $\\Pi$ be a cuspidal auto
 morphic representation for GL(3) over a number field. We fix an integer $k
  \\geq 2$ and we assume that the symmetric $m$th power lifts of $\\Pi$ are
  automorphic for $m \\leq k$\, cuspidal for $m < k$\, and that certain ass
 ociated Rankin–Selberg products are automorphic. In this setting\, we bo
 und the number of cuspidal isobaric summands in the $k$th symmetric power 
 lift. In particular\, we show it is bounded above by 3 for $k \\geq 7$\, a
 nd bounded above by 2 when $k \\geq 19$ with $k$ congruent to 1 mod 3. We 
 will also discuss the analogous problem for GL(4).\n\nThis will include a 
 pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/38/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Evan O'Dorney (Princeton University)
DTSTART:20210527T210000Z
DTEND:20210527T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/39
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/39/
 ">Arithmetic statistics of $H^1(K\, T)$</a>\nby Evan O'Dorney (Princeton U
 niversity) as part of UCSD number theory seminar\n\nLecture held in normal
 ly APM 7321\, currently online.\n\nAbstract\nCoclasses in a Galois cohomol
 ogy group $H^1(K\, T)$ parametrize extensions of a number field with certa
 in Galois group. It is natural to want to count these coclasses with gener
 al local conditions and with respect to a discriminant-like invariant. In 
 joint work with Brandon Alberts\, I present a novel tool for studying this
 : harmonic analysis on adelic cohomology\, modeled after the celebrated us
 e of harmonic analysis on the adeles in Tate's thesis. This leads to a mor
 e illuminating explanation of a fact previously noticed by Alberts\, namel
 y that the Dirichlet series counting such coclasses is a finite sum of Eul
 er products\; and we nail down the asymptotic count of coclasses in satisf
 ying generality.\n\nIn the pre-talk\, I will give a rundown on the needed 
 background in Galois cohomology\, etale algebras\, the local Tate pairing\
 , and Poitou-Tate duality.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/39/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kelly Isham (University of California Irvine)
DTSTART:20210603T210000Z
DTEND:20210603T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/40
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/40/
 ">Asymptotic growth of orders in a fixed number field via subrings in $\\m
 athbb{Z}^n$</a>\nby Kelly Isham (University of California Irvine) as part 
 of UCSD number theory seminar\n\nLecture held in normally APM 7321\, curre
 ntly online.\n\nAbstract\nLet $K$ be a number field of degree $n$ and $\\m
 athcal{O}_K$ be its ring of integers. An order in $\\mathcal{O}_K$ is a fi
 nite index subring that contains the identity. A major open question in ar
 ithmetic statistics asks for the asymptotic growth of orders in $K$. In th
 is talk\, we will give the best known lower bound for this asymptotic grow
 th. The main strategy is to relate orders in $\\mathcal{O}_K$ to subrings 
 in $\\mathbb{Z}^n$ via zeta functions. Along the way\, we will give lower 
 bounds for the asymptotic growth of subrings in $\\mathbb{Z}^n$ and for th
 e number of index $p^e$ subrings in $\\mathbb{Z}^n$. We will also discuss 
 analytic properties of these zeta functions.\n\nThere will be a pretalk at
  1:30 Pacific time.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/40/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kiran Kedlaya (UCSD)
DTSTART:20211007T210000Z
DTEND:20211007T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/42
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/42/
 ">Orders of abelian varieties over F_2</a>\nby Kiran Kedlaya (UCSD) as par
 t of UCSD number theory seminar\n\nLecture held in APM 7321 and online.\n\
 nAbstract\nWe describe several recent results on orders of abelian varieti
 es over $\\mathbb{F}_2$: every positive integer occurs as the order of an 
 ordinary abelian variety over $\\mathbb{F}_2$ (joint with E. Howe)\; every
  positive integer occurs infinitely often as the order of a simple abelian
  variety over $\\mathbb{F}_2$\; the geometric decomposition of the simple 
 abelian varieties over $\\mathbb{F}_2$ can be described explicitly (joint 
 with T. D'Nelly-Warady)\; and the relative class number one problem for fu
 nction fields is reduced to a finite computation (work in progress).\n\nAl
 l of these results rely on the relationship between isogeny classes of abe
 lian varieties over finite fields and Weil polynomials given by the work o
 f Weil and Honda-Tate. With these results in hand\, most of the work is to
  construct algebraic integers satisfying suitable archimedean constraints.
 \n\nTalk to be given in person and streamed via Zoom.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/42/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jeff Lagarias (Michigan)
DTSTART:20211014T210000Z
DTEND:20211014T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/43
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/43/
 ">Complex Equiangular Lines and the Stark Conjectures</a>\nby Jeff Lagaria
 s (Michigan) as part of UCSD number theory seminar\n\nLecture held in APM 
 7321 and online.\n\nAbstract\nThis talk is expository. It describes the hi
 story of  an exciting connection made by physicists between an unsolved \n
 problem in combinatorial design theory- the existence of maximal sets of $
 d^2$  complex equiangular lines in ${\\mathbb C}^d$-\nrephrased as a probl
 em in quantum information theory\, and topics\n in algebraic number theory
  involving class fields of real quadratic fields. Work of my former studen
 t\nGene Kopp recently  uncovered a surprising\, deep (unproved!) connectio
 n with\nthe Stark conjectures. For infinitely many dimensions $d$  he pred
 icts the existence of maximal equiangular sets\, \nconstructible by a spec
 ific recipe starting from suitable Stark units\, in the rank one case. Num
 erically computing\nspecial values at $s=0$ of suitable L-functions then p
 ermits recovering the units numerically to high precision\, \nthen reconst
 ructing them exactly\, then testing they satisfy suitable extra algebraic 
 identities to yield a construction\nof  the set of equiangular lines. It h
 as been carried out for $d=5\, 11\, 17$ and $23$.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/43/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Thomas Grubb (UCSD)
DTSTART:20211021T210000Z
DTEND:20211021T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/44
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/44/
 ">A cut-by-curves criterion for overconvergence of $F$-isocrystals</a>\nby
  Thomas Grubb (UCSD) as part of UCSD number theory seminar\n\nLecture held
  in APM 7321 and online.\n\nAbstract\nLet $X$ be a smooth\, geometrically 
 irreducible scheme over a finite field of characteristic $p > 0$. With res
 pect to rigid cohomology\, $p$-adic coefficient objects on $X$ come in two
  types: convergent $F$-isocrystals and the subcategory of overconvergent $
 F$-isocrystals. Overconvergent isocrystals are related to $\\ell$-adic eta
 le objects ($\\ell\\neq p$) via companions theory\, and as such it is desi
 rable to understand when an isocrystal is overconvergent. We show (under a
  geometric tameness hypothesis) that a convergent $F$-isocrystal $E$ is ov
 erconvergent if and only if its restriction to all smooth curves on $X$ is
 . The technique reduces to an algebraic setting where we use skeleton shea
 ves and crystalline companions to compare $E$ to an isocrystal which is pa
 tently overconvergent. Joint with Kiran Kedlaya and James Upton.\n\npre-ta
 lk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/44/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rahul Dalal (Johns Hopkins)
DTSTART:20211028T210000Z
DTEND:20211028T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/45
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/45/
 ">Counting level-1\, quaternionic automorphic representations on $G_2$</a>
 \nby Rahul Dalal (Johns Hopkins) as part of UCSD number theory seminar\n\n
 Lecture held in APM 7321 and online.\n\nAbstract\nQuaternionic automorphic
  representations are one attempt to generalize to other groups the special
  place holomorphic modular forms have among automorphic representations of
  $GL_2$. Like holomorphic modular forms\, they are defined by having their
  real component be one of a particularly nice class (in this case\, called
  quaternionic discrete series). We count quaternionic automorphic represen
 tations on the exceptional group $G_2$ by developing a $G_2$ version of th
 e classical Eichler-Selberg trace formula for holomorphic modular forms. \
 n\nThere are two main technical difficulties. First\, quaternionic discret
 e series come in L-packets with non-quaternionic members and standard inva
 riant trace formula techniques cannot easily distinguish between discrete 
 series with real component in the same L-packet. Using the more modern sta
 ble trace formula resolves this issue. Second\, quaternionic discrete seri
 es do not satisfy a technical condition of being "regular"\, so the trace 
 formula can a priori pick up unwanted contributions from automorphic repre
 sentations with non-tempered components at infinity. Applying some computa
 tions of Mundy\, this miraculously does not happen for our specific case o
 f quaternionic representations on $G_2$. \n\nFinally\, we are only studyin
 g level-1 forms\, so we can apply some tricks of Chenevier and Taïbi to r
 educe the problem to counting representations on the compact form of $G_2$
  and certain pairs of modular forms. This avoids involved computations on 
 the geometric side of the trace formula.\n\n30 min pre-talk before\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/45/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Linus Hamann (Princeton)
DTSTART:20211104T210000Z
DTEND:20211104T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/46
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/46/
 ">Compatibility of the Fargues-Scholze and Gan-Takeda local Langlands</a>\
 nby Linus Hamann (Princeton) as part of UCSD number theory seminar\n\nLect
 ure held in APM 6402 and online.\n\nAbstract\nGiven a prime $p$\, a finite
  extension $L/\\mathbb{Q}_{p}$\, a connected $p$-adic reductive group $G/L
 $\, and a smooth irreducible representation $\\pi$ of $G(L)$\, Fargues-Sch
 olze recently attached a semisimple Weil parameter to such $\\pi$\, giving
  a general candidate for the local Langlands correspondence. It is natural
  to ask whether this construction is compatible with known instances of th
 e correspondence after semisimplification. For $G = GL_{n}$ and its inner 
 forms\,  Fargues-Scholze and Hansen-Kaletha-Weinstein show that the corres
 pondence is compatible with the correspondence of Harris-Taylor/Henniart. 
 We verify a similar compatibility for $G = GSp_{4}$ and its unique non-spl
 it inner form $G = GU_{2}(D)$\, where $D$ is the quaternion division algeb
 ra over $L$\, assuming that $L/\\mathbb{Q}_{p}$ is unramified and $p > 2$.
  In this case\, the local Langlands correspondence has been constructed by
  Gan-Takeda and Gan-Tantono. Analogous to the case of $GL_{n}$ and its inn
 er forms\, this compatibility is proven by describing the Weil group actio
 n on the cohomology of a local Shimura variety associated to $GSp_{4}$\, u
 sing basic uniformization of abelian type Shimura varieties due to Shen\, 
 combined with various global results of Kret-Shin and Sorensen on Galois r
 epresentations in the cohomology of global Shimura varieties associated to
  inner forms of $GSp_{4}$ over a totally real field. After showing the par
 ameters are the same\, we apply some ideas from the geometry of the Fargue
 s-Scholze construction explored recently by Hansen\, to give a more precis
 e description of the cohomology of this local Shimura variety\, verifying 
 a strong form of the Kottwitz conjecture in the process.\n\npre-talk at 1:
 20pm.\n\nThe talk will be given via Zoom\, but we will meet in the lecture
  hall as usual.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/46/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriel Dorfsman-Hopkins (UC Berkeley)
DTSTART:20211118T220000Z
DTEND:20211118T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/47
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/47/
 ">Untilting Line Bundles on Perfectoid Spaces</a>\nby Gabriel Dorfsman-Hop
 kins (UC Berkeley) as part of UCSD number theory seminar\n\nLecture held i
 n APM 7321 and online.\n\nAbstract\nLet $X$ be a perfectoid space with til
 t $X^\\flat$.  We build a natural map $\\theta:\\Pic X^\\flat\\to\\lim\\Pi
 c X$ where the (inverse) limit is taken over the $p$-power map\, and show 
 that $\\theta$ is an isomorphism if $R = \\Gamma(X\,\\sO_X)$ is a perfecto
 id ring.  As a consequence we obtain a characterization of when the Picard
  groups of $X$ and $X^\\flat$ agree in terms of the $p$-divisibility of $\
 \Pic X$.  The main technical ingredient is the vanishing of higher derived
  limits of the unit group $R^*$\, whence the main result follows from the 
 Grothendieck spectral sequence.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/47/
END:VEVENT
BEGIN:VEVENT
SUMMARY:James Upton (UC San Diego)
DTSTART:20211202T220000Z
DTEND:20211202T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/48
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/48/
 ">Newton Polygons of Abelian $L$-Functions on Curves</a>\nby James Upton (
 UC San Diego) as part of UCSD number theory seminar\n\nLecture held in APM
  7321 and online.\n\nAbstract\nLet $X$ be a smooth\, affine\, geometricall
 y connected curve over a finite field of characteristic $p > 2$. Let $\\rh
 o:\\pi_1(X) \\to \\mathbb{C}^\\times$ be a character of finite order $p^n$
 . If $\\rho\\neq 1$\, then the Artin $L$-function $L(\\rho\,s)$ is a polyn
 omial\, and a theorem of Kramer-Miller states that its $p$-adic Newton pol
 ygon $\\mathrm{NP}(\\rho)$ is bounded below by a certain Hodge polygon $\\
 mathrm{HP}(\\rho)$ which is defined in terms of local monodromy invariants
 . In this talk we discuss the interaction between the polygons $\\mathrm{N
 P}(\\rho)$ and $\\mathrm{HP}(\\rho)$. Our main result states that if $X$ i
 s ordinary\, then $\\mathrm{NP}(\\rho)$ and $\\mathrm{HP}(\\rho)$ share a 
 vertex if and only if there is a corresponding vertex shared by certain "l
 ocal" Newton and Hodge polygons associated to each ramified point of $\\rh
 o$. As an application\, we give a local criterion that is necessary and su
 fficient for $\\mathrm{NP}(\\rho)$ and $\\mathrm{HP}(\\rho)$ to coincide. 
 This is joint work with Joe Kramer-Miller.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/48/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting (UCSD)
DTSTART:20210923T210000Z
DTEND:20210923T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/49
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/49/
 ">Organizational meeting (Zoom only)</a>\nby Organizational meeting (UCSD)
  as part of UCSD number theory seminar\n\nLecture held in APM 7321 and onl
 ine.\n\nAbstract\nThis meeting will take place exclusively over Zoom.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/49/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting
DTSTART:20220106T220000Z
DTEND:20220106T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/50
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/50/
 ">Organizational meeting (Zoom only)</a>\nby Organizational meeting as par
 t of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\nA
 bstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/50/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tong Liu (Purdue)
DTSTART:20220113T220000Z
DTEND:20220113T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/51
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/51/
 ">Prismatic F-crystal and lattice in crystalline representation</a>\nby To
 ng Liu (Purdue) as part of UCSD number theory seminar\n\n\nAbstract\nIn th
 is talk\, I will explain a theorem of Bhatt-Scholze: the equivalence betwe
 en prismatic $F$-crystal and $\\mathbb Z_p$-lattices inside crystalline re
 presentation\, and how to extend this theorem to allow more general types 
 of base ring like Tate algebra ${\\mathbb Z}_p \\langle t^{\\pm 1}\\rangle
 $.  This is a joint work with Heng Du\, Yong-Suk Moon and Koji Shimizu.  \
 n\nThis is a talk in integral $p$-adic Hodge theory.  So in the pre-talk\,
  I will explain the motivations and base ideas in integral $p$-adic Hodge 
 theory.\n\nonline only\; pre-talk at 1:30\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/51/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Claudius Heyer (Münster)
DTSTART:20220120T220000Z
DTEND:20220120T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/52
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/52/
 ">The left adjoint of derived parabolic induction</a>\nby Claudius Heyer (
 Münster) as part of UCSD number theory seminar\n\n\nAbstract\nRecent adva
 nces in the theory of smooth mod $p$ representations of a $p$-adic\nreduct
 ive group $G$ involve more and more derived methods.  It becomes\nincreasi
 ngly clear that the proper framework to study smooth mod $p$\nrepresentati
 ons is the derived category $D(G)$.\n\nI will talk about smooth mod $p$ re
 presentations and highlight their\nshortcomings compared to\, say\, smooth
  complex representations of $G$.  After\nexplaining how the situation impr
 oves in the derived category\, I will spend the\nremaining time on the lef
 t adjoint of the derived parabolic induction functor.\n\nThere will be a p
 re-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/52/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Petar Bakic (Utah)
DTSTART:20220127T220000Z
DTEND:20220127T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/53
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/53/
 ">Howe duality for exceptional theta correspondences</a>\nby Petar Bakic (
 Utah) as part of UCSD number theory seminar\n\nLecture held in online.\n\n
 Abstract\nThe theory of local theta correspondence is built up from two ma
 in ingredients: a reductive dual pair inside a symplectic group\, and a We
 il representation of its metaplectic cover. Exceptional correspondences ar
 ise similarly: dual pairs inside exceptional groups can be constructed usi
 ng so-called Freudenthal Jordan algebras\, while the minimal representatio
 n provides a suitable replacement for the Weil representation. The talk wi
 ll begin by recalling these constructions. Focusing on a particular dual p
 air\, we will explain how one obtains Howe duality for the correspondence 
 in question. Finally\, we will discuss applications of these results. The 
 new work in this talk is joint with Gordan Savin.\n\npre-talk at 1:30pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/53/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alex Smith (Stanford)
DTSTART:20220203T220000Z
DTEND:20220203T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/54
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/54/
 ">$2^k$-Selmer groups and Goldfeld's conjecture</a>\nby Alex Smith (Stanfo
 rd) as part of UCSD number theory seminar\n\nLecture held in APM 6402 and 
 online.\n\nAbstract\nTake $E$ to be an elliptic curve over a number field 
 whose four torsion obeys certain technical conditions. In this talk\, we w
 ill outline a proof that 100% of the quadratic twists of $E$ have rank at 
 most one. To do this\, we will find the distribution of $2^k$-Selmer ranks
  in this family for every positive $k$. We will also show how are techniqu
 es may be applied to find the distribution of $2^k$-class groups of quadra
 tic fields.\n\nThe pre-talk will focus on the definition of Selmer groups.
  We will also give some context for the study of the arithmetic statistics
  of these groups.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/54/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabrielle De Micheli (UCSD)
DTSTART:20220210T220000Z
DTEND:20220210T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/55
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/55/
 ">Lattice Enumeration for Tower NFS: a 521-bit Discrete Logarithm Computat
 ion</a>\nby Gabrielle De Micheli (UCSD) as part of UCSD number theory semi
 nar\n\nLecture held in APM 6402 and online.\n\nAbstract\nThe Tower variant
  of the Number Field Sieve (TNFS) is known to be asymptotically the most e
 fficient algorithm to solve the discrete logarithm problem in finite field
 s of medium characteristics\, when the extension degree is composite. A ma
 jor obstacle to an efficient implementation of TNFS is the collection of a
 lgebraic relations\, as it happens in dimensions greater than 2. This requ
 ires the construction of new sieving algorithms which remain efficient as 
 the dimension grows. In this talk\,  I will present how we overcome this d
 ifficulty by considering a lattice enumeration algorithm which we adapt to
  this specific context. We also consider a new sieving area\, a high-dimen
 sional sphere\, whereas previous sieving algorithms for the classical NFS 
 considered an orthotope. Our new sieving technique leads to a much smaller
  running time\, despite the larger dimension of the search space\, and eve
 n when considering a larger target\, as demonstrated by a record computati
 on we performed in a 521-bit finite field GF(p^6). The target finite field
  is of the same form as finite fields used in recent zero-knowledge proofs
  in some blockchains. This is the first reported implementation of TNFS.\n
 \nIn the pre-talk\, I will briefly present the core ideas of the quadratic
  sieve algorithm and its evolution to the Number Field Sieve algorithm.\n\
 npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/55/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aaron Pollack (UCSD)
DTSTART:20220217T220000Z
DTEND:20220217T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/56
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/56/
 ">A Cohen-Zagier modular form on G_2</a>\nby Aaron Pollack (UCSD) as part 
 of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\n\nA
 bstract\nI will report on joint work with Spencer Leslie where we define a
 n analogue of the Cohen-Zagier Eisenstein series to the exceptional group 
 $G_2$. Recall that the Cohen-Zagier Eisenstein series is a weight $3/2$ mo
 dular form whose Fourier coefficients see the class numbers of imaginary q
 uadratic fields. We define a particular modular form of weight $1/2$ on $G
 _2$\, and prove that its Fourier coefficients see (certain torsors for) th
 e 2-torsion in the narrow class groups of totally real cubic fields. In pa
 rticular: 1) we define a notion of modular forms of half-integral weight o
 n certain exceptional groups\, 2) we prove that these modular forms have a
  nice theory of Fourier coefficients\, and 3) we partially compute the Fou
 rier coefficients of a particular nice example on G_2.\n\npre-talk at 1:20
 pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/56/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Paulina Fust (Duisburg-Essen)
DTSTART:20220224T220000Z
DTEND:20220224T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/57
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/57/
 ">Continuous group cohomology and Ext-groups</a>\nby Paulina Fust (Duisbur
 g-Essen) as part of UCSD number theory seminar\n\nLecture held in APM 6402
  and online.\n\nAbstract\nWe prove that the continuous cohomology groups o
 f a $p$-adic reductive group with coefficients in an admissible unitary $\
 \mathbb{Q}_p$-Banach space representation $\\Pi$ are finite-dimensional an
 d compare them to certain Ext-groups. As an application of this result\, w
 e show that the continuous cohomology of $SL_2(\\mathbb{Q}_p) $ with value
 s in non-ordinary irreducible $\\mathbb{Q}_p$-Banach space representations
  of $GL_2(\\mathbb{Q}_p)$ vanishes.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/57/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Annie Carter (UCSD)
DTSTART:20220303T170000Z
DTEND:20220303T180000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/58
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/58/
 ">Two-variable polynomials with dynamical Mahler measure zero</a>\nby Anni
 e Carter (UCSD) as part of UCSD number theory seminar\n\n\nAbstract\nIntro
 duced by Lehmer in 1933\, the classical Mahler measure of a complex ration
 al function $P$ in one or more variables is given by integrating $\\log|P(
 x_1\, \\ldots\, x_n)|$ over the unit torus. Lehmer asked whether the Mahle
 r measures of integer polynomials\, when nonzero\, must be bounded away fr
 om zero\, a question that remains open to this day. In this talk we genera
 lize Mahler measure by associating it with a discrete dynamical system $f:
  \\mathbb{C} \\to \\mathbb{C}$\, replacing the unit torus by the $n$-fold 
 Cartesian product of the Julia set of $f$ and integrating with respect to 
 the equilibrium measure on the Julia set. We then characterize those two-v
 ariable integer polynomials with dynamical Mahler measure zero\, condition
 al on a dynamical version of Lehmer's conjecture.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/58/
END:VEVENT
BEGIN:VEVENT
SUMMARY:David Urbanik (Toronto)
DTSTART:20220310T220000Z
DTEND:20220310T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/59
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/59/
 ">Effective Methods for Shafarevich Problems</a>\nby David Urbanik (Toront
 o) as part of UCSD number theory seminar\n\nLecture held in APM 7321.\n\nA
 bstract\nGiven a smooth projective family $f : X \\to S$ defined over\nthe
  ring of integers of a number field\, the Shafarevich problem is to\ndescr
 ibe those fibres of f which have everywhere good reduction. This\ncan be i
 nterpreted as asking for the dimension of the Zariski closure\nof the set 
 of integral points of $S$\, and is ultimately a difficult\ndiophantine que
 stion about which little is known as soon as the\ndimension of $S$ is at l
 east 2. Recently\, Lawrence and Venkatesh gave a\ngeneral strategy for add
 ressing such problems which requires as input\nlower bounds on the monodro
 my of f over essentially arbitrary closed\nsubvarieties of $S$. In this ta
 lk we review their ideas\, and describe\nrecent work which gives a fully e
 ffective method for computing these\nlower bounds. This gives a fully effe
 ctive strategy for solving\nShafarevich-type problems for essentially arbi
 trary families $f$.\n\nThis week's talk is in APM 7321 rather than APM 640
 2.\n\npre-talk at 1:20 pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/59/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Amit Ophir (Hebrew U.)
DTSTART:20220414T170000Z
DTEND:20220414T180000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/60
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/60/
 ">Invariant norms on the p-adic Schrödinger representation</a>\nby Amit O
 phir (Hebrew U.) as part of UCSD number theory seminar\n\nLecture held in 
 online.\n\nAbstract\nMotivated by questions about a p-adic Fourier transfo
 rm\, we study invariant norms on the p-adic Schrödinger representations o
 f Heisenberg groups. These Heisenberg groups are p-adic\, and the Schrodin
 ger representations are explicit irreducible smooth representations that p
 lay an important role in their representation theory. \nClassically\, the 
 field of coefficients is taken to be the complex numbers and\, among other
  things\, one studies the unitary completions of the representations (whic
 h are well understood). By taking the field of coefficients to be an exten
 sion of the p-adic numbers\, we can consider completions that better captu
 re the p-adic topology\, but at the cost of losing the Haar measure and th
 e $L^2$-norm. Nevertheless\, we establish a rigidity property for a family
  of norms (parametrized by a Grassmannian) that are invariant under the ac
 tion of the Heisenberg group.\nThe irreducibility of some Banach represent
 ations follows as a result. The proof uses "q-arithmetics".\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/60/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brian Lawrence (UCLA)
DTSTART:20220428T210000Z
DTEND:20220428T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/61
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/61/
 ">Sparsity of Integral Points on Moduli Spaces of Varieties</a>\nby Brian 
 Lawrence (UCLA) as part of UCSD number theory seminar\n\nLecture held in A
 PM 6402 and online.\n\nAbstract\nInteresting moduli spaces don't have many
  integral points.  More precisely\, if X is a variety over a number field\
 , admitting a variation of Hodge structure whose associate period map is i
 njective\, then the number of S-integral points on X of height at most H g
 rows more slowly than H^{\\epsilon}\, for any positive \\epsilon.  This is
  a sort of weak generalization of the Shafarevich conjecture\; it is a con
 sequence of a point-counting theorem of Broberg\, and the largeness of the
  fundamental group of X.  Joint with Ellenberg and Venkatesh.\n\npre-talk 
 at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/61/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Michelle Manes (U. Hawaii)
DTSTART:20220519T210000Z
DTEND:20220519T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/62
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/62/
 ">Iterating Backwards in Arithmetic Dynamics</a>\nby Michelle Manes (U. Ha
 waii) as part of UCSD number theory seminar\n\nLecture held in APM 6402 an
 d online.\n\nAbstract\nIn classical real and complex dynamics\, one studie
 s topological and analytic properties of orbits of points under iteration 
 of self-maps of $\\mathbb R$ or $\\mathbb C$ (or more generally self-maps 
 of a real or complex manifold). In arithmetic dynamics\, a more recent sub
 ject\, one likewise studies properties of orbits of self-maps\, but with a
  number theoretic flavor. Many of the motivating problems in arithmetic dy
 namics come via analogy with classical problems in arithmetic geometry: ra
 tional and integral points on varieties correspond to rational and integra
 l points in orbits\; torsion points on abelian varieties correspond to per
 iodic and preperiodic points of rational maps\; and abelian varieties with
  complex multiplication correspond to post-critically finite rational maps
 .\n\nThis analogy focuses on forward iteration\, but sometimes surprising 
 and interesting results can be found by thinking instead about pre-images 
 of rational points under iteration. In this talk\, we will give some backg
 round and motivation for the field of arithmetic dynamics in order to desc
 ribe some of these "backwards iteration" results\, including uniform bound
 edness for rational pre-images and open image results for Galois represent
 ations associated to dynamical systems.\n\nA pre-talk for graduate student
 s will describe some of the motivating results in arithmetic geometry.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/62/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Koji Shimizu (UC Berkeley)
DTSTART:20220526T210000Z
DTEND:20220526T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/63
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/63/
 ">Robba site and Robba cohomology</a>\nby Koji Shimizu (UC Berkeley) as pa
 rt of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\n
 \nAbstract\nWe will discuss a $p$-adic cohomology theory for rigid analyti
 c varieties with overconvergent structure (dagger spaces) over a local fie
 ld of characteristic $p$. After explaining the motivation\, we will define
  a site (Robba site) and discuss its basic properties.\n\nThe main talk wi
 ll be preceded by a pre-talk.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/63/
END:VEVENT
BEGIN:VEVENT
SUMMARY:David Hansen (MPIM)
DTSTART:20220407T210000Z
DTEND:20220407T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/64
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/64/
 ">Duality and the p-adic Jacquet-Langlands correspondence</a>\nby David Ha
 nsen (MPIM) as part of UCSD number theory seminar\n\nLecture held in APM 6
 402 and online.\n\nAbstract\nIn joint work with Lucas Mann\, we establish 
 several new properties of the p-adic Jacquet-Langlands functor defined by 
 Scholze in terms of the cohomology of the Lubin-Tate tower. In particular\
 , we prove a duality theorem\, establish bounds on Gelfand-Kirillov dimens
 ion\, prove some non-vanishing results\, and show a kind of partial Künne
 th formula. The key new tool is the six functor formalism with solid almos
 t $\\mathcal{O}^+/p$-coefficients developed recently by Mann.\n\nPre-talk\
 n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/64/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting
DTSTART:20220331T210000Z
DTEND:20220331T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/65
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/65/
 ">Organizational meeting (Zoom only)</a>\nby Organizational meeting as par
 t of UCSD number theory seminar\n\nLecture held in online.\nAbstract: TBA\
 n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/65/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anthony Kling (U. Arizona)
DTSTART:20220421T210000Z
DTEND:20220421T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/66
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/66/
 ">Comparison of Integral Structures on the Space of Modular Forms of Full 
 Level $N$</a>\nby Anthony Kling (U. Arizona) as part of UCSD number theory
  seminar\n\nLecture held in APM 6402 and online.\n\nAbstract\nLet $N\\geq3
 $ and $r\\geq1$ be integers and $p\\geq2$ be a prime such that $p\\nmid N$
 . One can consider two different integral structures on the space of modul
 ar forms over $\\mathbb{Q}$\, one coming from arithmetic via $q$-expansion
 s\, the other coming from geometry via integral models of modular curves. 
 Both structures are stable under the Hecke operators\; furthermore\, their
  quotient is finite torsion. Our goal is to investigate the exponent of th
 e annihilator of the quotient. We will apply results due to Brian Conrad t
 o the situation of modular forms of even weight and level $\\Gamma(Np^{r})
 $ over $\\mathbb{Q}_{p}(\\zeta_{Np^{r}})$ to obtain an upper bound for the
  exponent. We also use Klein forms to construct explicit modular forms of 
 level $p^{r}$ whenever $p^{r}>3$\, allowing us to compute a lower bound wh
 ich agrees with the upper bound. Hence we are able to compute the exponent
  precisely.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/66/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Masahiro Nakahara (U. Washington)
DTSTART:20220505T210000Z
DTEND:20220505T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/67
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/67/
 ">Uniform potential density for rational points on algebraic groups and el
 liptic K3 surfaces</a>\nby Masahiro Nakahara (U. Washington) as part of UC
 SD number theory seminar\n\nLecture held in APM 6402 and online.\n\nAbstra
 ct\nA variety satisfies potential density if it contains a dense subset of
  rational points after extending its ground field by a finite degree. A co
 llection of varieties satisfies uniform potential density if that degree c
 an be uniformly bounded. I will discuss this property for connected algebr
 aic groups of a fixed dimension and elliptic K3 surfaces. This is joint wo
 rk with Kuan-Wen Lai.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/67/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gyujin Oh (Princeton)
DTSTART:20220512T210000Z
DTEND:20220512T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/68
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/68/
 ">A cohomological approach to harmonic Maass forms</a>\nby Gyujin Oh (Prin
 ceton) as part of UCSD number theory seminar\n\nLecture held in APM 6402 a
 nd online.\n\nAbstract\nWe interpret a harmonic Maass form as a variant of
  a local cohomology class of the modular curve. This is not only amenable 
 to algebraic interpretation\, but also nicely generalized to other Shimura
  varieties\, avoiding the barrier of Koecher's principle\, which could be 
 useful for developing a generalization of Borcherds lifts. In this talk\, 
 we will exhibit how the theory looks like in the case of Hilbert modular v
 arities.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/68/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alexandra Florea (UC Irvine)
DTSTART:20220602T210000Z
DTEND:20220602T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/69
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/69/
 ">Negative moments of the Riemann zeta function</a>\nby Alexandra Florea (
 UC Irvine) as part of UCSD number theory seminar\n\nLecture held in APM 64
 02 and online.\n\nAbstract\nI will talk about recent work towards a conjec
 ture of Gonek regarding negative shifted moments of the Riemann zeta funct
 ion. I will explain how to obtain asymptotic formulas when the shift in th
 e Riemann zeta function is big enough\, and how we can obtain non-trivial 
 upper bounds for smaller shifts. Joint work with H. Bui.\n\npre-talk at 1:
 20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/69/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting (UCSD)
DTSTART:20220929T210000Z
DTEND:20220929T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/70
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/70/
 ">Organizational meeting (APM 7321)</a>\nby Organizational meeting (UCSD) 
 as part of UCSD number theory seminar\n\nLecture held in APM 6402 and onli
 ne.\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/70/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Klevdal (UCSD)
DTSTART:20221006T210000Z
DTEND:20221006T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/71
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/71/
 ">Strong independence of $\\ell$ for Shimura varieties</a>\nby Christian K
 levdal (UCSD) as part of UCSD number theory seminar\n\nLecture held in APM
  6402 and online.\n\nAbstract\n(Joint with Stefan Patrikis.) In this talk\
 , we discuss a strong form of independence of $\\ell$ for canonical $\\ell
 $-adic local systems on Shimura varieties\, and sketch a proof of this for
  Shimura varieties arising from adjoint groups whose simple factors have r
 eal rank $\\geq 2$. Notably\, this includes all adjoint Shimura varieties 
 which are not of abelian type. The key tools used are the existence of com
 panions for $\\ell$-adic local systems and the superrigidity theorem of Ma
 rgulis for lattices in Lie groups of real rank $\\geq 2$.  \n\nThe indepen
 dence of $\\ell$ is motivated by a conjectural description of Shimura vari
 eties as moduli spaces of motives. For certain Shimura varieties that aris
 e as a moduli space of abelian varieties\, the strong independence of $\\e
 ll$ is proven (at the level of Galois representations) by recent work of K
 isin and Zhou\, refining the independence of $\\ell$ on the Tate module gi
 ven by Deligne's work on the Weil conjectures.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/71/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shishir Agrawal (UCSD)
DTSTART:20221013T210000Z
DTEND:20221013T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/72
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/72/
 ">From category $\\mathcal{O}^\\infty$ to locally analytic representations
 </a>\nby Shishir Agrawal (UCSD) as part of UCSD number theory seminar\n\nL
 ecture held in APM 6402 and online.\n\nAbstract\nLet $G$ be a $p$-adic red
 uctive group with $\\mathfrak{g} = \\mathrm{Lie}(G)$. I will summarize wor
 k with Matthias Strauch in which we construct an exact functor from catego
 ry $\\mathcal{O}^\\infty$\, the extension closure of the Bernstein-Gelfand
 -Gelfand category $\\mathcal{O}$ inside the category of $U(\\mathfrak{g})$
 -modules\, into the category of admissible locally analytic representation
 s of $G$. This expands on an earlier construction by Sascha Orlik and Matt
 hias Strauch. A key role in our new construction is played by $p$-adic log
 arithms on tori\, and representations in the image of this functor are rel
 ated to some that are known to arise in the context of the $p$-adic Langla
 nds program.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/72/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jon Aycock (UCSD)
DTSTART:20221020T210000Z
DTEND:20221020T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/73
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/73/
 ">Differential operators for overconvergent Hilbert modular forms</a>\nby 
 Jon Aycock (UCSD) as part of UCSD number theory seminar\n\nLecture held in
  APM 6402 and online.\n\nAbstract\nIn 1978\, Katz gave a construction of t
 he $p$-adic $L$-function of a CM field by using a $p$-adic analog of the M
 aass--Shimura operators acting on $p$-adic Hilbert modular forms. However\
 , this $p$-adic Maass--Shimura operator is only defined over the ordinary 
 locus\, which restricted Katz's choice of $p$ to one that splits in the CM
  field. In 2021\, Andreatta and Iovita extended Katz's construction to all
  $p$ for quadratic imaginary fields using overconvergent differential oper
 ators constructed by Harron--Xiao and Urban\, which act on elliptic modula
 r forms. Here we give a construction of such overconvergent differential o
 perators which act on Hilbert modular forms.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/73/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rusiru Gambheera Arachchige (UCSD)
DTSTART:20221027T210000Z
DTEND:20221027T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/74
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/74/
 ">An unconditional equivariant main conjecture in Iwasawa theory</a>\nby R
 usiru Gambheera Arachchige (UCSD) as part of UCSD number theory seminar\n\
 nLecture held in APM 6402 and online.\n\nAbstract\nIn 2015 Greither and Po
 pescu constructed a new class of Iwasawa modules\, which are the number fi
 eld analogues of $p-$adic realizations of Picard 1- motives constructed by
  Deligne. They proved an equivariant main conjecture by computing the Fitt
 ing ideal of these new modules over the appropriate profinite group ring. 
 This is an integral\, equivariant refinement of Wiles' classical main conj
 ecture. As a consequence they proved a refinement of the Brumer-Stark conj
 ecture away from 2. All of the above was proved under the assumption that 
 the relevant prime $p$ is odd and that the appropriate classical Iwasawa $
 \\mu$–invariants vanish. Recently\, Dasgupta and Kakde proved the Brumer
 -Stark conjecture\, away from 2\, unconditionally\, using a generalization
  of Ribet's method. We use the Dasgupta-Kakde results to prove an uncondit
 ional equivariant main conjecture\, which is a generalization of that of G
 reither and Popescu. As applications of our main theorem we prove a genera
 lization of a certain case of the main result of Dasgupta-Kakde and we com
 pute the Fitting ideal of a certain naturally arising Iwasawa module. This
  is joint work with Cristian Popescu.\n\npre-talk at 1:20\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/74/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Finn McGlade (UCSD)
DTSTART:20221103T210000Z
DTEND:20221103T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/75
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/75/
 ">Fourier coefficients on quaternionic U(2\,n)</a>\nby Finn McGlade (UCSD)
  as part of UCSD number theory seminar\n\nLecture held in APM 6402 and onl
 ine.\n\nAbstract\nLet $E/\\mathbb{Q}$ be an imaginary quadratic extension 
 and suppose $G$ is the unitary group attached to hermitian space over $E$ 
 of signature $(2\,n)$. The symmetric domain $X$ attached to $G$ is a quate
 rnionic Kahler manifold. In the late nineties N. Wallach studied harmonic 
 analysis on $X$ in the context of this quaternionic structure. He establis
 hed a multiplicity one theorem for spaces of generalized Whittaker periods
  appearing in the cohomology of certain $G$-bundles on $X$. \n\nWe prove a
 n analogous multiplicity one statement for some degenerate generalized Whi
 ttaker periods and give explicit formulas for these periods in terms of mo
 dified K-Bessel functions. Our results give a refinement of the Fourier ex
 pansion of certain automorphic forms on $G$ which are quaternionic discret
 e series at infinity. As an application\, we study the Fourier expansion o
 f cusp forms on $G$ which arise as theta lifts of holomorphic modular form
 s on quasi-split $\\mathrm{U}(1\,1)$. We show that these cusp forms can be
  normalized so that all their Fourier coefficients are algebraic numbers. 
 (joint with Anton Hilado and Pan Yan)\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/75/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kalyani Kansal (Johns Hopkins)
DTSTART:20221110T220000Z
DTEND:20221110T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/76
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/76/
 ">Intersections of components of Emerton-Gee stack for $\\mathrm{GL}_2$</a
 >\nby Kalyani Kansal (Johns Hopkins) as part of UCSD number theory seminar
 \n\nLecture held in APM 6402 and online.\n\nAbstract\nThe Emerton-Gee stac
 k for $\\mathrm{GL}_2$ is a stack of $(\\varphi\, \\Gamma)$-modules whose 
 reduced part $\\mathcal{X}_{2\, \\mathrm{red}}$ can be viewed as a moduli 
 stack of mod $p$ representations of a $p$-adic Galois group. We compute cr
 iteria for codimension one intersections of the irreducible components of 
 $\\mathcal{X}_{2\, \\mathrm{red}}$\, and interpret them in sheaf-theoretic
  terms. We also give a cohomological criterion for the number of top-dimen
 sional components in a codimension one intersection.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/76/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Romyar Sharifi (UCLA)
DTSTART:20221117T220000Z
DTEND:20221117T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/77
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/77/
 ">Cohomology of intermediate quotients</a>\nby Romyar Sharifi (UCLA) as pa
 rt of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\n
 \nAbstract\nWe will discuss Galois cohomology groups of “intermediate”
  quotients of an induced module\, which sit between Iwasawa cohomology up 
 a tower and cohomology over the ground field. Special elements in Iwasawa 
 cohomology that arise from Euler systems become divisible by a certain Eul
 er factor upon norming down to the ground field. In certain instances\, th
 ere are reasons to wonder whether this divisibility can also hold for the 
 image in intermediate cohomology. Using “intermediate” Coleman maps\, 
 we shall see that the situation locally at $p$ is as nice as one could ima
 gine.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/77/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christopher Keyes (Emory)
DTSTART:20221201T220000Z
DTEND:20221201T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/78
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/78/
 ">Local solubility in families of superelliptic curves</a>\nby Christopher
  Keyes (Emory) as part of UCSD number theory seminar\n\nLecture held in AP
 M 6402 and online.\n\nAbstract\nIf we choose at random an integral binary 
 form $f(x\, z)$ of fixed degree $d$\, what is the probability that the sup
 erelliptic curve with equation  $C \\colon: y^m = f(x\, z)$ has a $p$-adic
  point\, or better\, points everywhere locally? In joint work with Lea Ben
 eish\, we show that the proportion of forms $f(x\, z)$ for which $C$ is ev
 erywhere locally soluble is positive\, given by a product of local densiti
 es. By studying these local densities\, we produce bounds which are suitab
 le enough to pass to the large $d$ limit. In the specific case of curves o
 f the form $y^3 = f(x\, z)$ for a binary form of degree 6\, we determine t
 he probability of everywhere local solubility to be 96.94%\, with the exac
 t value given by an explicit infinite product of rational function express
 ions.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/78/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Simon Marshall (Wisconsin)
DTSTART:20230209T220000Z
DTEND:20230209T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/79
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/79/
 ">Large values of eigenfunctions on hyperbolic manifolds</a>\nby Simon Mar
 shall (Wisconsin) as part of UCSD number theory seminar\n\nLecture held in
  APM 6402 and online.\n\nAbstract\nIt is a folklore conjecture that the su
 p norm of a Laplace eigenfunction on a compact hyperbolic surface grows mo
 re slowly than any positive power of the eigenvalue.  In dimensions three 
 and higher\, this was shown to be false by Iwaniec-Sarnak and Donnelly.  I
  will present joint work with Farrell Brumley that strengthens these resul
 ts\, and extends them to locally symmetric spaces associated to $\\mathrm{
 SO}(p\,q)$.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/79/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jef Laga (Cambridge)
DTSTART:20230309T220000Z
DTEND:20230309T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/80
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/80/
 ">Arithmetic statistics via graded Lie algebras</a>\nby Jef Laga (Cambridg
 e) as part of UCSD number theory seminar\n\nLecture held in APM 6402 and o
 nline.\n\nAbstract\nI will explain how various results in arithmetic stati
 stics by Bhargava\, Gross\, Shankar and others on 2-Selmer groups of Jacob
 ians of (hyper)elliptic curves can be organised and reproved using the the
 ory of graded Lie algebras\, following earlier work of Thorne. This gives 
 a uniform proof of these results and yields new theorems for certain famil
 ies of non-hyperelliptic curves. I will also mention some applications to 
 rational points on certain families of curves.\n\nThe talk will involve a 
 mixture of representation theory\, number theory and algebraic geometry an
 d I will assume no familiarity with arithmetic statistics.\n\npre-talk at 
 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/80/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Longke Tang (Princeton)
DTSTART:20230119T220000Z
DTEND:20230119T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/81
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/81/
 ">Prismatic Poincaré duality</a>\nby Longke Tang (Princeton) as part of U
 CSD number theory seminar\n\nLecture held in APM 6402 and online.\n\nAbstr
 act\nPrismatic cohomology is a new p-adic cohomology theory introduced by 
 Bhatt and Scholze that specializes to various well-known cohomology theori
 es such as étale\, de Rham and crystalline. I will roughly recall the pro
 perties of this cohomology and explain how to prove its Poincaré duality.
 \n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/81/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nolan Wallach (UC San Diego)
DTSTART:20230126T220000Z
DTEND:20230126T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/82
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/82/
 ">The Whittaker Inversion Theorem and some applications</a>\nby Nolan Wall
 ach (UC San Diego) as part of UCSD number theory seminar\n\nLecture held i
 n APM 6402 and online.\n\nAbstract\nThe Whittaker Plancherel theorem appea
 red as Chapter 15 in my two volume book\, Real Reductive Groups. It was me
 ant to be an application of Harish-Chandra’s Plancherel Theorem.  As it 
 turns out\, there are serious gaps in the proof given in the books. At the
  same time as I was doing my research on the subject\, Harish-Chandra was 
 also working on it. His approach was very different from mine and appears 
 as part of Volume 5 of his collected works\; which consists of three piece
 s of research by Harish-Chandra that were incomplete at his death and orga
 nized and edited by Gangolli and Varadarajan. Unfortunately\,  it also doe
 s not contain a proof of the theorem. There was a complication in the proo
 f of this result that caused substantial difficulties which had to do with
  the image of the analog of Harish-Chandra’s method of descent. In this 
 lecture I will explain how one can complete the proof using a recent resul
 t of Raphael Beuzzart-Plessis. I will also give an application of the resu
 lt to the Fourier transforms of automorphic functions at cusps.\n\n(This s
 eminar will be given remotely\, but there will still be a live audience in
  the lecture room.)\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/82/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Xu Gao (UC Santa Cruz)
DTSTART:20230316T210000Z
DTEND:20230316T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/83
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/83/
 ">$p$-adic representations and simplicial distance in Bruhat-Tits building
 s</a>\nby Xu Gao (UC Santa Cruz) as part of UCSD number theory seminar\n\n
 Lecture held in APM 6402 and online.\n\nAbstract\n$p$-adic representations
  are important objects in number theory\, and stable lattices serve as a c
 onnection between the study of ordinary and modular representations. These
  stable lattices can be understood as stable vertices in Bruhat-Tits build
 ings. From this viewpoint\, the study of fixed point sets in these buildin
 gs can aid research on $p$-adic representations. The simplicial distance h
 olds an important role as it connects the combinatorics of lattices and th
 e geometry of root systems. In particularly\, the fixed-point sets of Moy-
 Prasad subgroups are precisely the simplicial balls. In this talk\, I'll e
 xplain those findings and compute their simplicial volume under certain co
 nditions.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/83/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sameera Vemulapalli (Princeton)
DTSTART:20230223T220000Z
DTEND:20230223T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/84
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/84/
 ">Counting low degree number fields with almost prescribed successive mini
 ma</a>\nby Sameera Vemulapalli (Princeton) as part of UCSD number theory s
 eminar\n\nLecture held in APM 6402 and online.\n\nAbstract\nThe successive
  minima of an order in a degree n number field are n real numbers encoding
  information about the Euclidean structure of the order. How many orders i
 n degree n number fields are there with almost prescribed successive minim
 a\, fixed Galois group\, and bounded discriminant? In this talk\, I will a
 ddress this question for n = 3\, 4\, 5. The answers\, appropriately interp
 reted\, turn out to be piecewise linear functions on certain convex bodies
 . If time permits\, I will also discuss function field analogues of this p
 roblem.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/84/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yujie Xu (MIT)
DTSTART:20230302T220000Z
DTEND:20230302T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/85
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/85/
 ">Hecke algebras for p-adic groups and the explicit Local Langlands Corres
 pondence for G_2</a>\nby Yujie Xu (MIT) as part of UCSD number theory semi
 nar\n\nLecture held in APM 6402 and online.\n\nAbstract\nI will talk about
  my recent joint work with Aubert where we prove the Local Langlands Conje
 cture for G_2 (explicitly). This uses our earlier results on Hecke algebra
 s attached to Bernstein components of reductive p-adic groups\, as well as
  an expected property on cuspidal support\, along with a list of character
 izing properties. In particular\, we obtain "mixed" L-packets containing F
 -singular supercuspidals and non-supercuspidals.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/85/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Arghya Sadhukhan (Maryland)
DTSTART:20230112T220000Z
DTEND:20230112T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/86
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/86/
 ">Understanding the dimension of some (union of) affine Deligne-Lusztig va
 rieties via the quantum Bruhat graph</a>\nby Arghya Sadhukhan (Maryland) a
 s part of UCSD number theory seminar\n\nLecture held in APM 6402 and onlin
 e.\n\nAbstract\nThe study of affine Deligne-Lusztig varieties (ADLVs) $X_w
 (b)$ and their certain union $X(\\mu\,b)$ has been crucial in understandin
 g mod-$p$ reduction of Shimura varieties\; for instance\, precise informat
 ion about the connected components of ADLVs (in the hyperspecial level) ha
 s proved to be useful in Kisin's proof of the Langlands-Rapoport conjectur
 e. On the other hand\, first introduced in the context of enumerative geom
 etry to describe the quantum cohomology ring of complex flag varieties\, q
 uantum Bruhat graphs have found recent applications in solving certain pro
 blems on the ADLVs. I will survey such developments and report on my work 
 surrounding a dimension formula for $X(\\mu\,b)$ in the quasi-split case\,
  as well as some partial description of the dimension and top-dimensional 
 irreducible components in the non quasi-split case.\n\npre-talk at 1:20pm\
 n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/86/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniel Vallieres (CSU Chico/UC San Diego)
DTSTART:20230216T220000Z
DTEND:20230216T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/87
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/87/
 ">Iwasawa theory and graph theory</a>\nby Daniel Vallieres (CSU Chico/UC S
 an Diego) as part of UCSD number theory seminar\n\nLecture held in APM 640
 2 and online.\n\nAbstract\nAnalogies between number theory and graph theor
 y have been studied for quite some times now.  During the past few years\,
  it has been observed in particular that there is an analogy between class
 ical Iwasawa theory and some phenomena in graph theory.  In this talk\, we
  will explain this analogy and present some of the results that have been 
 obtained so far in this area.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/87/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gilyoung Cheong (UC Irvine)
DTSTART:20230202T220000Z
DTEND:20230202T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/88
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/88/
 ">Polynomial equations for matrices over integers modulo a prime power and
  the cokernel of a random matrix</a>\nby Gilyoung Cheong (UC Irvine) as pa
 rt of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\n
 \nAbstract\nOver a commutative ring of finite cardinality\, how many $n \\
 times n$ matrices satisfy a polynomial equation? In this talk\, I will exp
 lain how to solve this question when the ring is given by integers modulo 
 a prime power and the polynomial is square-free modulo the prime. Then I w
 ill discuss how this question is related to the distribution of the cokern
 el of a random matrix and the Cohen--Lenstra heuristics. This is joint wor
 k with Yunqi Liang and Michael Strand\, as a result of a summer undergradu
 ate research I mentored.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/88/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Keegan Ryan (UC San Diego)
DTSTART:20230420T210000Z
DTEND:20230420T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/89
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/89/
 ">Fast Practical Lattice Reduction through Iterated Compression</a>\nby Ke
 egan Ryan (UC San Diego) as part of UCSD number theory seminar\n\nLecture 
 held in APM 6402 and online.\n\nAbstract\nWe introduce a new lattice basis
  reduction algorithm with approximation guarantees analogous to the LLL al
 gorithm and practical performance that far exceeds the current state of th
 e art. We achieve these results by iteratively applying precision manageme
 nt techniques within a recursive algorithm structure and show the stabilit
 y of this approach. We analyze the asymptotic behavior of our algorithm\, 
 and show that the heuristic running time is $O(n^{\\omega}(C+n)^{1+\\varep
 silon})$ for lattices of dimension $n$\, $\\omega\\in (2\,3]$ bounding the
  cost of size reduction\, matrix multiplication\, and QR factorization\, a
 nd $C$ bounding the log of the condition number of the input basis $B$. Th
 is yields a running time of $O\\left(n^\\omega (p + n)^{1 + \\varepsilon}\
 \right)$ for precision $p = O(\\log \\|B\\|_{max})$ in common applications
 . Our algorithm is fully practical\, and we have published our implementat
 ion. We experimentally validate our heuristic\, give extensive benchmarks 
 against numerous classes of cryptographic lattices\, and show that our alg
 orithm significantly outperforms existing implementations.\n\npre-talk at 
 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/89/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hanlin Cai (Utah)
DTSTART:20230504T210000Z
DTEND:20230504T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/91
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/91/
 ">Perfectoid signature and local étale fundamental group</a>\nby Hanlin C
 ai (Utah) as part of UCSD number theory seminar\n\nLecture held in APM 640
 2 and online.\n\nAbstract\nIn this talk I'll talk about a (perfectoid) mix
 ed characteristic version of F-signature and Hilbert-Kunz multiplicity by 
 utilizing the perfectoidization functor of Bhatt-Scholze and Faltings' nor
 malized length. These definitions coincide with the classical theory in eq
 ual characteristic. Moreover\, perfectoid signature detects BCM regularity
  and transforms similarly to F-signature or normalized volume under quasi-
 étale maps. As a consequence\, we can prove that BCM-regular rings have f
 inite local étale fundamental group and torsion part of their divisor cla
 ss groups. This is joint work with Seungsu Lee\, Linquan Ma\, Karl Schwede
  and Kevin Tucker.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/91/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrew Kobin (Emory)
DTSTART:20230518T210000Z
DTEND:20230518T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/92
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/92/
 ">Categorifying zeta and L-functions</a>\nby Andrew Kobin (Emory) as part 
 of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\n\nA
 bstract\nZeta and L-functions are ubiquitous in modern number theory. Whil
 e some work in the past has brought homotopical methods into the theory of
  zeta functions\, there is in fact a lesser-known zeta function that is na
 tive to homotopy theory. Namely\, every suitably finite decomposition spac
 e (aka 2-Segal space) admits an abstract zeta function as an element of it
 s incidence algebra. In this talk\, I will show how many 'classical' zeta 
 functions in number theory and algebraic geometry can be realized in this 
 homotopical framework. I will also discuss work in progress towards a cate
 gorification of motivic zeta and L-functions.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/92/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Samit Dasgupta (Duke)
DTSTART:20230511T210000Z
DTEND:20230511T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/93
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/93/
 ">Ribet’s Lemma\, the Brumer-Stark Conjecture\, and the Main Conjecture<
 /a>\nby Samit Dasgupta (Duke) as part of UCSD number theory seminar\n\nLec
 ture held in APM 6402 and online.\n\nAbstract\nIn 1976\, Ken Ribet used mo
 dular techniques to prove an important relationship between class groups o
 f cyclotomic fields and special values of the zeta function.  Ribet’s me
 thod was generalized to prove the Iwasawa Main Conjecture for odd primes p
  by Mazur-Wiles over Q and by Wiles over arbitrary totally real fields.  \
 n\nCentral to Ribet’s technique is the construction of a nontrivial exte
 nsion of one Galois character by another\, given a Galois representation s
 atisfying certain properties.  Throughout the literature\, when working in
 tegrally at p\, one finds the assumption that the two characters are not c
 ongruent mod p.  For instance\, in Wiles’ proof of the Main Conjecture\,
  it is assumed that p is odd precisely because the relevant characters mig
 ht be congruent modulo 2\, though they are necessarily distinct modulo any
  odd prime.\n\nIn this talk I will present a proof of Ribet’s Lemma in t
 he case that the characters are residually indistinguishable.  As arithmet
 ic applications\, one obtains a proof of the Iwasawa Main Conjecture for t
 otally real fields at p=2.  Moreover\, we complete the proof of the Brumer
 -Stark conjecture by handling the localization at p=2\, building on joint 
 work with Mahesh Kakde for odd p.  Our results yield the full Equivariant 
 Tamagawa Number conjecture for the minus part of the Tate motive associate
 d to a CM abelian extension of a totally real field\, which has many impor
 tant corollaries.\n\nThis is joint work with Mahesh Kakde\, Jesse Silliman
 \, and Jiuya Wang.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/93/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nha Truong (Hawaii)
DTSTART:20230406T210000Z
DTEND:20230406T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/94
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/94/
 ">Slopes of modular forms and geometry of eigencurves</a>\nby Nha Truong (
 Hawaii) as part of UCSD number theory seminar\n\nLecture held in APM 6402 
 and online.\n\nAbstract\nThe slopes of modular forms are the $p$-adic valu
 ations of the eigenvalues of the Hecke operators $T_p$. The study of slope
 s plays an important role in understanding the geometry of the eigencurves
 \, introduced by Coleman and Mazur. \n\nThe study of the slope began in th
 e 1990s when Gouvea and Mazur computed many numerical data and made severa
 l interesting conjectures. Later\, Buzzard\, Calegari\, and other people m
 ade more precise conjectures by studying the space of overconvergent modul
 ar forms. Recently\, Bergdall and Pollack introduced the ghost conjecture 
 that unifies the previous conjectures in most cases. The ghost conjecture 
 states that the slope can be predicted by an explicitly defined power seri
 es. We prove the ghost conjecture under a certain mild technical condition
 . In the pre-talk\, I will explain an example in the quaternionic setting 
 which was used as a testing ground for the proof. \nThis is joint work wit
 h Ruochuan Liu\, Liang Xiao\, and Bin Zhao.\n\npre-talk at 1:30pm (note un
 usual time)\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/94/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Somnath Jha (IIT Kanpur)
DTSTART:20230427T210000Z
DTEND:20230427T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/95
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/95/
 ">Rational cube sum problem</a>\nby Somnath Jha (IIT Kanpur) as part of UC
 SD number theory seminar\n\nLecture held in APM 6402 and online.\n\nAbstra
 ct\nThe classical Diophantine problem of determining  which integers can b
 e written as a sum of two rational cubes has a long history\; it includes 
 works of Sylvester\,  Selmer\, Satgé\, Leiman  and the recent work of Alp
 öge-Bhargava-Shnidman-Burungale-Skinner.  In this talk\, we will  use  Se
 lmer groups of elliptic curves and integral binary cubic forms to study so
 me cases of the rational cube sum problem.  This talk is based on  joint w
 orks with D. Majumdar\, P. Shingavekar and B. Sury.\n\npre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/95/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alina Bucur (UC San Diego)
DTSTART:20230413T210000Z
DTEND:20230413T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/96
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/96/
 ">Counting $D_4$ quartic extensions of a number field ordered by discrimin
 ant</a>\nby Alina Bucur (UC San Diego) as part of UCSD number theory semin
 ar\n\nLecture held in APM 6402 and online.\n\nAbstract\nA guiding question
  in number theory\, specifically in arithmetic statistics\, is counting nu
 mber fields of fixed degree and Galois group as their discriminants grow t
 o infinity.  We will discuss the history of this question and take a close
 r look at the story in the case of quartic fields. In joint work with Flor
 ea\, Serrano Lopez\, and Varma\, we extend and make explicit the counts of
   extensions of an arbitrary number field that was done over the rationals
  by Cohen\, Diaz y Diaz\, and Olivier.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/96/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Catherine Hsu (Swarthmore College)
DTSTART:20230601T210000Z
DTEND:20230601T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/97
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/97/
 ">Explicit non-Gorenstein R=T via rank bounds</a>\nby Catherine Hsu (Swart
 hmore College) as part of UCSD number theory seminar\n\nLecture held in AP
 M 6402 and online.\n\nAbstract\nIn his seminal work on modular curves and 
 the Eisenstein ideal\, Mazur studied the existence of congruences between 
 certain Eisenstein series and newforms\, proving that Eisenstein ideals as
 sociated to weight 2 cusp forms of prime level are locally principal. In t
 his talk\, we'll explore generalizations of Mazur's result to squarefree l
 evel\, focusing on recent work\, joint with P. Wake and C. Wang-Erickson\,
  about a non-optimal level N that is the product of two distinct primes an
 d where the Galois deformation ring is not expected to be Gorenstein. Firs
 t\, we will outline a Galois-theoretic criterion for the deformation ring 
 to be as small as possible\, and when this criterion is satisfied\, deduce
  an R=T theorem. Then we'll discuss some of the techniques required to com
 putationally verify the criterion.\n\nPre-talk\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/97/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting
DTSTART:20230928T210000Z
DTEND:20230928T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/98
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/98/
 ">Organizational meeting (no Zoom)</a>\nby Organizational meeting as part 
 of UCSD number theory seminar\n\nLecture held in APM 6402 and online.\nAbs
 tract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/98/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aaron Pollack (UC San Diego)
DTSTART:20231005T210000Z
DTEND:20231005T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/99
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/99/
 ">Arithmeticity of quaternionic modular forms on G_2</a>\nby Aaron Pollack
  (UC San Diego) as part of UCSD number theory seminar\n\nLecture held in A
 PM 6402 and online.\n\nAbstract\nQuaternionic modular forms (QMFs) on the 
 split exceptional group G_2 are a special class of automorphic functions o
 n this group\, whose origin goes back to work of Gross-Wallach and Gan-Gro
 ss-Savin.  While the group G_2 does not possess any holomorphic modular fo
 rms\, the quaternionic modular forms seem to be able to be a good substitu
 te.  In particular\, QMFs on G_2 possess a semi-classical Fourier expansio
 n and Fourier coefficients\, just like holomorphic modular forms on Shimur
 a varieties.  I will explain the proof that the cuspidal QMFs of even weig
 ht at least 6 admit an arithmetic structure: there is a basis of the space
  of all such cusp forms\, for which every Fourier coefficient of every ele
 ment of this basis lies in the cyclotomic extension of Q.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/99/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tony Feng (UC Berkeley)
DTSTART:20231116T220000Z
DTEND:20231116T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/100
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/100
 /">Mirror symmetry and the Breuil-Mezard Conjecture</a>\nby Tony Feng (UC 
 Berkeley) as part of UCSD number theory seminar\n\n\nAbstract\nThe Breuil-
 Mezard Conjecture predicts the existence of hypothetical "Breuil-Mezard cy
 cles" that should govern congruences between mod p automorphic forms on a 
 reductive group G. Most of the progress thus far has been concentrated on 
 the case G = GL_2\, which has several special features. I will talk about 
 joint work with Bao Le Hung on a new approach to the Breuil-Mezard Conject
 ure\, which applies for arbitrary groups (and in particular\, in arbitrary
  rank). It is based on the intuition that the Breuil-Mezard conjecture is 
 analogous to homological mirror symmetry.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/100/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shou-Wu Zhang (Princeton)
DTSTART:20231109T220000Z
DTEND:20231109T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/101
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/101
 /">Triple product L-series and Gross–Kudla–Schoen cycles</a>\nby Shou-
 Wu Zhang (Princeton) as part of UCSD number theory seminar\n\nLecture held
  in APM 6402 and online.\n\nAbstract\nIn this talk\, we consider a conject
 ure by Gross and Kudla that relates the derivatives of triple-product L-fu
 nctions \nfor three modular forms and the height pairing of the Gross—Sc
 hoen cycles on Shimura curves.\nThen\, we sketch a proof of a generalizati
 on of this conjecture for Hilbert modular forms in the spherical case. Thi
 s is a report of work in progress with Xinyi Yuan and Wei Zhang\, with hel
 p from Yifeng Liu.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/101/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Robin Zhang (MIT)
DTSTART:20231109T204000Z
DTEND:20231109T214000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/102
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/102
 /">Harris–Venkatesh plus Stark</a>\nby Robin Zhang (MIT) as part of UCSD
  number theory seminar\n\nLecture held in APM 6402 and online.\n\nAbstract
 \nThe class number formula describes the behavior of the Dedekind zeta fun
 ction at s = 0 and s = 1. The Stark and Gross conjectures extend the class
  number formula\, describing the behavior of Artin L-functions and p-adic 
 L-functions at s = 0 and s = 1 in terms of units. The Harris–Venkatesh c
 onjecture describes the residue of Stark units modulo p\, giving a modular
  analogue to the Stark and Gross conjectures while also serving as the fir
 st verifiable part of the broader conjectures of Venkatesh\, Prasanna\, an
 d Galatius. In this talk\, I will draw an introductory picture\, formulate
  a unified conjecture combining Harris–Venkatesh and Stark for weight on
 e modular forms\, and describe the proof of this in the imaginary dihedral
  case.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/102/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kiran Kedlaya (UC San Diego)
DTSTART:20231102T210000Z
DTEND:20231102T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/103
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/103
 /">The affine cone of a Fargues-Fontaine curve</a>\nby Kiran Kedlaya (UC S
 an Diego) as part of UCSD number theory seminar\n\nLecture held in APM 640
 2 and online.\n\nAbstract\nThe Fargues-Fontaine curve associated to an alg
 ebraically closed nonarchimedean field of characteristic $p$ is a fundamen
 tal geometric object in $p$-adic Hodge theory. Via the tilting equivalence
  it is related to the Galois theory of finite extensions of Q_p\; it also 
 occurs in Fargues's program to geometrize the local Langlands corresponden
 ce for such fields.\n\nRecently\, Peter Dillery and Alex Youcis have propo
 sed using a related object\, the "affine cone" over the aforementioned cur
 ve\, to incorporate some recent insights of Kaletha into Fargues's program
 . I will summarize what we do and do not yet know\, particularly about vec
 tor bundles on this and some related spaces (all joint work in progress wi
 th Dillery and Youcis).\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/103/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jon Aycock (UC San Diego)
DTSTART:20231207T220000Z
DTEND:20231207T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/104
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/104
 /">A p-adic Family of Quaternionic Modular Forms on a Group of Type G_2</a
 >\nby Jon Aycock (UC San Diego) as part of UCSD number theory seminar\n\nL
 ecture held in APM 7218.\n\nAbstract\nThe concept of p-adic families of au
 tomorphic forms has far reaching applications in number theory. In this ta
 lk\, we will discuss one of the first examples of such a family\, built fr
 om the Eisenstein series\, before allowing this to inform a construction o
 f a family on an exceptional group of type G_2.\n\npre-talk at 1:20pm in A
 PM 6402\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/104/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Klevdal (UC San Diego)
DTSTART:20231019T210000Z
DTEND:20231019T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/105
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/105
 /">p-adic periods of admissible pairs</a>\nby Christian Klevdal (UC San Di
 ego) as part of UCSD number theory seminar\n\nLecture held in APM 6402 and
  online.\n\nAbstract\nIn this talk\, we study a Tannakian category of admi
 ssible pairs\, which arise naturally when one is comparing etale and de Rh
 am cohomology of p-adic formal schemes. Admissible pairs are parameterized
  by local Shimura varieties and their non-minuscule generalizations\, whic
 h admit period mappings to de Rham affine Grassmannians. After reviewing t
 his theory\, we will state a result characterizing the basic admissible pa
 irs that admit CM in terms of transcendence of their periods. This result 
 can be seen as a p-adic analogue of a theorem of Cohen and Shiga-Wolfhart 
 characterizing CM abelian varieties in terms of transcendence of their per
 iods. All work is joint with Sean Howe.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/105/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Finley McGlade (UC San Diego)
DTSTART:20231130T220000Z
DTEND:20231130T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/106
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/106
 /">A Level 1 Maass Spezialschar for Modular Forms on $\\mathrm{SO}_8$</a>\
 nby Finley McGlade (UC San Diego) as part of UCSD number theory seminar\n\
 nLecture held in APM 7218 and online.\n\nAbstract\nThe classical Spezialsc
 har is the subspace of the space of\nholomorphic modular forms on  $\\math
 rm{Sp}_4(\\mathbb{Z})$ whose\nFourier coefficients satisfy a particular sy
 stem of linear equations. An\nequivalent characterization of the Spezialsc
 har can be obtained by\ncombining work of Maass\, Andrianov\, and Zagier\,
  whose work identifies\nthe Spezialschar in terms of a theta-lift from\n$\
 \widetilde{\\mathrm{SL}_2}$. Inspired by work of Gan-Gross-Savin\,\nWeissm
 an and Pollack have developed a theory of modular forms on the\nsplit adjo
 int group of type D_4. In this setting we describe an analogue\nof the cla
 ssical Spezialschar\, in which Fourier coefficients are used to\ncharacter
 ize those modular forms which arise as theta lifts from\nholomorphic forms
  on $\\mathrm{Sp}_4(\\mathbb{Z})$.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/106/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eugenia Rosu (Leiden)
DTSTART:20240118T220000Z
DTEND:20240118T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/107
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/107
 /">A higher degree Weierstrass function</a>\nby Eugenia Rosu (Leiden) as p
 art of UCSD number theory seminar\n\nLecture held in APM 7321.\n\nAbstract
 \nI will discuss recent developments and ongoing work for algebraic and p-
 adic aspects of L-functions. Interest in p-adic properties of values of L-
 functions originated with Kummer’s study of congruences between values o
 f the Riemann zeta function at negative odd integers\, as part of his atte
 mpt to understand class numbers of cyclotomic extensions. After presenting
  an approach to studying analogous congruences for more general classes of
  L-functions\, I will conclude by introducing ongoing joint work of G. Ros
 so\, S. Shah\, and myself (concerning Spin L-functions for GSp_6). I will 
 explain how this work fits into the context of earlier developments\, whil
 e also indicating where new technical challenges arise. All who are curiou
 s about this topic are welcome at this talk\, even without prior experienc
 e with p-adic L-functions or Spin L-functions.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/107/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shahed Sharif (CSU San Marcos)
DTSTART:20240215T220000Z
DTEND:20240215T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/108
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/108
 /">Number theory and quantum computing: Algorithmists\, Assemble!</a>\nby 
 Shahed Sharif (CSU San Marcos) as part of UCSD number theory seminar\n\nLe
 cture held in APM 7321.\n\nAbstract\nQuantum computing made its name by so
 lving a problem in number theory\; namely\, determining if factoring could
  be accomplished efficiently. Since then\, there has been immense progress
  in development of quantum algorithms related to number theory. I'll give 
 a perhaps idiosyncratic overview of the computational tools quantum comput
 ers bring to the table\, with the goal of inspiring the audience to find n
 ew problems that quantum computers can solve.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/108/
END:VEVENT
BEGIN:VEVENT
SUMMARY:John Yin (Wisconsin)
DTSTART:20240125T220000Z
DTEND:20240125T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/109
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/109
 /">A Chebotarev Density Theorem over Local Fields</a>\nby John Yin (Wiscon
 sin) as part of UCSD number theory seminar\n\nLecture held in APM 7321.\n\
 nAbstract\nI will present an analog of the Chebotarev Density Theorem whic
 h works over local fields. As an application\, I will use it to prove a co
 njecture of Bhargava\, Cremona\, Fisher\, and Gajović. This is joint work
  with Asvin G and Yifan Wei.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/109/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jessica Fintzen (Bonn)
DTSTART:20240112T220000Z
DTEND:20240112T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/111
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/111
 /">Representations of p-adic groups and Hecke algebras</a>\nby Jessica Fin
 tzen (Bonn) as part of UCSD number theory seminar\n\nLecture held in APM 7
 321.\n\nAbstract\nAn explicit understanding of the category of all (smooth
 \, complex)\nrepresentations of p-adic groups provides an important tool i
 n the\nconstruction of an explicit and a categorical local Langlands\ncorr
 espondence and also has applications to the study of automorphic\nforms. T
 he category of representations of p-adic groups decomposes into\nsubcatego
 ries\, called Bernstein blocks\, which are indexed by equivalence\nclasses
  of so called supercuspidal representations of Levi subgroups. In\nthis ta
 lk\, I will give an overview of what we know about an explicit\nconstructi
 on of supercuspidal representations and about the structure of\nthe Bernst
 ein blocks. In particular\, I will discuss a joint project in\nprogress wi
 th Jeffrey Adler\, Manish Mishra and Kazuma Ohara in which we\nshow that g
 eneral Bernstein blocks are equivalent to much better\nunderstood depth-ze
 ro Bernstein blocks. This is achieved via an\nisomorphism of Hecke algebra
 s and allows to reduce a lot of problems\nabout the (category of) represen
 tations of p-adic groups to problems\nabout representations of finite grou
 ps of Lie type\, where answers are\noften already known or easier to achie
 ve.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/111/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aranya Lahiri (UC San Diego)
DTSTART:20240229T220000Z
DTEND:20240229T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/112
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/112
 /">Dagger groups and $p$-adic distribution algebras</a>\nby Aranya Lahiri 
 (UC San Diego) as part of UCSD number theory seminar\n\nLecture held in AP
 M 7321.\n\nAbstract\nLocally analytic representations were introduced by P
 eter Schneider and Jeremy Teitelbaum as a tool to understand $p$-adic Lang
 lands program. From the very beginning the theory of $p$-valued groups pla
 yed an instrumental role in the study of locally analytic representations.
  In a previous work we attached a rigid analytic group to a  $\\textit{$p$
 -saturated group}$ (a class of $p$-valued groups that contains uniform pro
 -$p$ groups and pro-$p$ Iwahori subgroups as examples). In this talk I wil
 l outline how to elevate the rigid group to a $\\textit{dagger group}$\, a
  group object in the category of dagger spaces as introduced by Elmar Gros
 se-Klönne. I will further introduce the space of $\\textit{overconvergent
  functions}$ and its strong dual the $\\textit{overconvergent distribution
  algebra}$ on such a group. Finally I will show that in analogy to the loc
 ally analytic distribution algebra of compact $p$-adic groups\, in the cas
 e of uniform pro-$p$ groups the overconvergent distribution algebra is a F
 r´echet-Stein algebra\, i.e.\, it is equipped with a desirable algebraic 
 structure. This is joint work with Claus Sorensen and Matthias Strauch.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/112/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ellen Eischen (Oregon)
DTSTART:20240530T210000Z
DTEND:20240530T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/113
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/113
 /">Algebraic and p-adic aspects of L-functions\, with a view toward Spin L
 -functions for GSp_6</a>\nby Ellen Eischen (Oregon) as part of UCSD number
  theory seminar\n\nLecture held in APM 6402 and online.\n\nAbstract\nI wil
 l discuss recent developments and ongoing work for\nalgebraic and p-adic a
 spects of L-functions. Interest in p-adic\nproperties of values of L-funct
 ions originated with Kummer’s study of\ncongruences between values of th
 e Riemann zeta function at negative odd\nintegers\, as part of his attempt
  to understand class numbers of\ncyclotomic extensions. After presenting a
 n approach to studying\nanalogous congruences for more general classes of 
 L-functions\, I will\nconclude by introducing ongoing joint work of G. Ros
 so\, S. Shah\, and\nmyself (concerning Spin L-functions for GSp_6). I will
  explain how this\nwork fits into the context of earlier developments\, wh
 ile also\nindicating where new technical challenges arise. All who are cur
 ious\nabout this topic are welcome at this talk\, even without prior exper
 ience\nwith p-adic L-functions or Spin L-functions.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/113/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mckenzie West (Wisconsin-Eau Claire)
DTSTART:20240208T220000Z
DTEND:20240208T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/114
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/114
 /">A Robust Implementation of an Algorithm to Solve the $S$-Unit Equation<
 /a>\nby Mckenzie West (Wisconsin-Eau Claire) as part of UCSD number theory
  seminar\n\nLecture held in APM 7321 and online.\n\nAbstract\nThe $S$-unit
  equation has vast applications in number theory.  We will discuss an impl
 ementation of an algorithm to solve the $S$-unit equation in the mathemati
 cal software Sage.  The mathematical foundation for this implementation an
 d some applications will be outlined\, including an asymptotic version of 
 Fermat's Last Theorem for totally real cubic number fields with bounded di
 scriminant in which 2 is totally ramified. We will conclude with a discuss
 ion on current and future work toward improving the existing Sage function
 ality.\n\npre-talk at 1:20\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/114/
END:VEVENT
BEGIN:VEVENT
SUMMARY:René Schoof (Rome 3)
DTSTART:20240307T220000Z
DTEND:20240307T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/115
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/115
 /">Greenberg’s $\\lambda=0$ conjecture</a>\nby René Schoof (Rome 3) as 
 part of UCSD number theory seminar\n\nLecture held in APM 7321.\n\nAbstrac
 t\nRecent and not so recent computations by Mercuri and Paoluzi\nhave veri
 fied Greenberg’s $\\lambda=0$ conjecture in Iwasawa theory\nin many case
 s. We discuss the conjecture and the computations.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/115/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting
DTSTART:20240404T210000Z
DTEND:20240404T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/116
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/116
 /">Organizational meeting</a>\nby Organizational meeting as part of UCSD n
 umber theory seminar\n\nLecture held in APM 6402 and online.\nAbstract: TB
 A\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/116/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jon Aycock (UC San Diego)
DTSTART:20240425T210000Z
DTEND:20240425T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/117
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/117
 /">Congruences Between Automorphic Forms</a>\nby Jon Aycock (UC San Diego)
  as part of UCSD number theory seminar\n\nLecture held in APM 6402 and onl
 ine.\n\nAbstract\nWe will introduce an analytic notion of automorphic form
 s. These automorphic forms encode arithmetic data by way of their Fourier 
 theory\, and we will explore two different families of automorphic forms w
 hich have interesting congruences between their Fourier coefficients.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/117/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wei Yin (UC San Diego)
DTSTART:20240502T210000Z
DTEND:20240502T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/118
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/118
 /">Higher Coates-Sinnott Conjectures for CM-Fields</a>\nby Wei Yin (UC San
  Diego) as part of UCSD number theory seminar\n\nLecture held in APM 6402 
 and online.\n\nAbstract\nThe classical Coates-Sinnott Conjecture and its r
 efinements predict the deep relationship between the special values of L-f
 unctions and the structure of the étale cohomology groups attached to num
 ber fields. In this talk\, we aim to delve deeper along this direction to 
 propose what we call the “Higher Coates-Sinnott Conjectures" which revea
 l more information about these two types of important arithmetic objects. 
 We introduce the conjectures we formulate and our work towards them. This 
 is joint work with C. Popescu.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/118/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nandagopal Ramachandran (UC San Diego)
DTSTART:20240509T210000Z
DTEND:20240509T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/119
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/119
 /">Euler factors in Drinfeld modules</a>\nby Nandagopal Ramachandran (UC S
 an Diego) as part of UCSD number theory seminar\n\nLecture held in APM 640
 2 and online.\n\nAbstract\nIn this talk\, I'll first give a quick introduc
 tion to the theory of Drinfeld modules and talk about an equivariant $L$-f
 unction associated to Drinfeld modules as defined by Ferrara-Higgins-Green
 -Popescu in their work on the ETNC. As is usual\, these $L$-functions are 
 defined as an infinite product of Euler factors\, and the main focus of th
 is talk is a result relating these Euler factors to a certain quotient of 
 Fitting ideals of some algebraically relevant modules. This is joint work 
 with Cristian Popescu.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/119/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bryan Hu (UC San Diego)
DTSTART:20240516T210000Z
DTEND:20240516T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/120
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/120
 /">Critical values of the adjoint L-function of U(2\,1) in the quaternioni
 c case</a>\nby Bryan Hu (UC San Diego) as part of UCSD number theory semin
 ar\n\nLecture held in APM 6402 and online.\n\nAbstract\nWe will discuss qu
 estions surrounding automorphic L-functions\, particularly Deligne’s con
 jecture about critical values of motivic L-functions. In particular\, we s
 tudy the adjoint L-function of U(2\,1). Hundley showed that a certain inte
 gral\, involving an Eisenstein series on the exceptional group G_2\, compu
 tes this L-function at unramified places. We discuss the computation of th
 is integral at the archimedean place for quaternionic modular forms\, and 
 how this relates to Deligne's conjecture.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/120/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Klevdal (UC San Diego)
DTSTART:20240523T210000Z
DTEND:20240523T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/121
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/121
 /">Local systems on Shimura varieties</a>\nby Christian Klevdal (UC San Di
 ego) as part of UCSD number theory seminar\n\nLecture held in APM 6402 and
  online.\n\nAbstract\nA large area of modern number theory (the Langlands 
 program) studies a deep correspondence between the representation theory o
 f Galois groups\, algebraic varieties and certain analytic objects (automo
 rphic forms). Many spectacular theorems have come from this area\, for exa
 mple the key insight in Wiles' proof of Fermat's last theorem was a connec
 tion between elliptic curves\, modular forms and Galois representations. \
 n\nThe goal of this talk is to explain how geometric constructions\, parti
 cularly related to Shimura varieties\, arise naturally in the Langlands pr
 ogram. I will then talk about joint work with Stefan Patrikis\, stating th
 at Galois representations arising from certain Shimura varieties satisfy t
 he properties predicted by the correspondence introduced above.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/121/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Claus Sorensen (UC San Diego)
DTSTART:20240411T210000Z
DTEND:20240411T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/122
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/122
 /">Projective smooth representations mod $p$</a>\nby Claus Sorensen (UC Sa
 n Diego) as part of UCSD number theory seminar\n\nLecture held in APM 6402
  and online.\n\nAbstract\nThis talk will be colloquial and geared towards 
 people from other fields. I will talk about smooth mod $p$ representations
  of $p$-adic Lie groups. In stark contrast to the complex case\, these cat
 egories typically do not have any (nonzero) projective objects. For reduct
 ive groups this is a byproduct of a stronger result on the derived functor
 s of smooth induction. The talk is based on joint work with Peter Schneide
 r.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/122/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Aranya Lahiri (UC San Diego)
DTSTART:20240418T210000Z
DTEND:20240418T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/123
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/123
 /">Distribution algebras of p-adic groups</a>\nby Aranya Lahiri (UC San Di
 ego) as part of UCSD number theory seminar\n\nLecture held in APM 6402 and
  online.\n\nAbstract\nMy goal will be to motivate why looking at distribut
 ion algebras associated to p-adic lie groups is natural in the context of 
 number theory. More specifically I will try to briefly outline their impor
 tance in the p-adic Langlands program. And then I will give a simple examp
 le of an overconvergent distribution algebra of certain kinds of  p-adic g
 roups with an eye towards illuminating techniques used in my work Dagger g
 roups and p-adic distribution algebras (joint w/ Matthias Strauch and Clau
 s Sorensen).\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/123/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chris Xu (UC San Diego)
DTSTART:20240606T210000Z
DTEND:20240606T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/124
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/124
 /">Rational points on modular curves via the moduli interpretation</a>\nby
  Chris Xu (UC San Diego) as part of UCSD number theory seminar\n\nLecture 
 held in APM 6402 and online.\n\nAbstract\nIn theory\, Chabauty-Coleman pro
 vides an explicit method to obtain rational points on any curve\, so long 
 as its genus exceeds its Mordell-Weil rank. In practice\, when applied to 
 modular curves\, we often encounter difficulties in finding a suitable pla
 ne model\, which only worsens as the genus increases. In this talk we desc
 ribe how to skip this step and instead work directly with the coarse modul
 i space. This is joint work with Steve Huang and Jun Bo Lau.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/124/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Organizational meeting
DTSTART:20241002T230000Z
DTEND:20241003T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/126
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/126
 /">Organizational meeting</a>\nby Organizational meeting as part of UCSD n
 umber theory seminar\n\nLecture held in APM 7321 and online.\nAbstract: TB
 A\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/126/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jennifer Johnson-Leung (University of Idaho)
DTSTART:20241023T230000Z
DTEND:20241024T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/127
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/127
 /">Rationality of certain power series attached to paramodular Siegel modu
 lar forms</a>\nby Jennifer Johnson-Leung (University of Idaho) as part of 
 UCSD number theory seminar\n\nLecture held in APM 7321 and online.\n\nAbst
 ract\nThe Euler product expression of the Dirichlet series of Fourier coef
 ficients of an elliptic modular eigenform follows from a formal identity i
 n the Hecke algebra for GL(2) with full level. In the case of Siegel modul
 ar forms of degree two with paramodular level\, the situation is more deli
 cate. In this talk\, I will present two rationality results. The first con
 cerns the Dirichlet series of radial Fourier coefficients for an eigenform
  of paramodular level divisible by the square of a prime. This result is a
 n application of the theory of stable Klingen vectors (joint work with Bro
 oks Roberts and Ralf Schmidt).  While we are able to calculate the action 
 of certain Hecke operators on eigenforms\, the structure of the Hecke alge
 bra of deep level is not known in general. However\, in the case of prime 
 level\, there is a robust description of the local Hecke algebra which yie
 lds a rationality result for a formal power series of Hecke operators (joi
 nt work with Joshua Parker and Brooks Roberts). In both cases\, we obtain 
 the expected local L-factor as the denominator of the rational function.\n
 \npre-talk at 3:00pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/127/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brandon Alberts (Eastern Michigan)
DTSTART:20241107T000000Z
DTEND:20241107T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/128
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/128
 /">Inductive methods for counting number fields</a>\nby Brandon Alberts (E
 astern Michigan) as part of UCSD number theory seminar\n\nLecture held in 
 APM 7321 and online.\n\nAbstract\nWe will discuss an inductive approach to
  determining the asymptotic number of G-extensions of a number field with 
 bounded discriminant\, and outline the proof of Malle's conjecture in nume
 rous new cases. This talk will include discussions of several examples dem
 onstrating the method.\n\npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/128/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Linli Shi (Connecticut)
DTSTART:20241121T000000Z
DTEND:20241121T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/129
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/129
 /">On higher regulators of Picard modular surfaces</a>\nby Linli Shi (Conn
 ecticut) as part of UCSD number theory seminar\n\nLecture held in APM 7321
  and online.\n\nAbstract\nThe Birch and Swinnerton-Dyer conjecture relates
  the leading coefficient of the L-function of an elliptic curve at its cen
 tral critical point to global arithmetic invariants of the elliptic curve.
  Beilinson’s conjectures generalize the BSD conjecture to formulas for v
 alues of motivic L-functions at non-critical points. In this talk\, I will
  relate motivic cohomology classes\, with non-trivial coefficients\, of Pi
 card modular surfaces to a non-critical value of the motivic L-function of
  certain automorphic representations of the group GU(2\,1).\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/129/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chris Xu (UC San Diego)
DTSTART:20241114T000000Z
DTEND:20241114T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/130
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/130
 /">Special cycles on $G_2$</a>\nby Chris Xu (UC San Diego) as part of UCSD
  number theory seminar\n\nLecture held in APM 7321 and online.\n\nAbstract
 \nOn the symmetric space for $G_2$\, there exist various submanifolds $G_D
 $ corresponding to the stabilizer of a norm $D$ vector. We show that when 
 a suitable automorphic form is integrated against the $G_D$\, the resultin
 g numbers assemble to give a half-integral weight classical modular form. 
 Although this is already implied by a result of Kudla-Millson\, we give a 
 simpler proof that avoids the complications in their paper.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/130/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yu Fu (Caltech)
DTSTART:20241205T000000Z
DTEND:20241205T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/131
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/131
 /">The p-adic analog of the Hecke orbit conjecture and density theorems to
 ward the p-adic monodromy</a>\nby Yu Fu (Caltech) as part of UCSD number t
 heory seminar\n\nLecture held in APM 7321 and online.\n\nAbstract\nThe Hec
 ke orbit conjecture predicts that Hecke symmetries characterize the centra
 l foliation on Shimura varieties over an algebraically closed field $k$ of
  characteristic $p$. The conjecture predicts that on the mod $p$ reduction
  of a Shimura variety\, any prime-to-p Hecke orbit is dense in the central
  leaf containing it\, and was recently proved by a series of nice papers.\
 nHowever\, the behavior of Hecke correspondences induced by isogenies betw
 een abelian varieties in characteristic $p$ and $p$-adically is significan
 tly different from the behavior in characteristic zero and under the topol
 ogy induced by Archimedean valuations. In this talk\,  we will formulate a
  $p$-adic analog of the Hecke orbit conjecture and investigate the $p$-adi
 c monodromy of $p$-adic Galois representations attached to points of Shimu
 ra varieties of Hodge type. We prove a density theorem for the locus of fo
 rmal neighborhood associated to the mod $p$ points of the Shimura variety 
 whose monodromy is large and use it to deduce the non-where density of Hec
 ke orbits under certain circumstances.\n\npre-talk at 3:00pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/131/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jon Aycock (UC San Diego)
DTSTART:20241016T230000Z
DTEND:20241017T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/132
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/132
 /">Jacobians of Graphs via Edges and Iwasawa Theory</a>\nby Jon Aycock (UC
  San Diego) as part of UCSD number theory seminar\n\nLecture held in APM 7
 321 and online.\n\nAbstract\nThe Jacobian (or sandpile group) is an algebr
 aic invariant of a graph that plays a similar role to the class group in c
 lassical number theory. There are multiple recent results controlling the 
 sizes of these groups in Galois towers of graphs that mimic the classical 
 results in Iwasawa theory\, though the connection to the values of the Iha
 ra zeta function often requires some adjustment. In this talk we will give
  a new way to view the Jacobian of a graph that more directly centers the 
 edges of the graph\, construct a module over the relevant Iwasawa algebra 
 that nearly corresponds to the interpolated zeta function\, and discuss wh
 ere the discrepancy comes from.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/132/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Chengyang Bao (UCLA)
DTSTART:20241030T230000Z
DTEND:20241031T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/133
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/133
 /">Computing crystalline deformation rings via the Taylor-Wiles-Kisin patc
 hing method</a>\nby Chengyang Bao (UCLA) as part of UCSD number theory sem
 inar\n\nLecture held in APM 7321 and online.\n\nAbstract\nCrystalline defo
 rmation rings play an important role in Kisin's proof of the Fontaine-Mazu
 r conjecture for GL2 in most cases. One crucial step in the proof is to pr
 ove the Breuil-Mezard conjecture on the Hilbert-Samuel multiplicity of the
  special fiber of the crystalline deformation ring. In pursuit of formulat
 ing a horizontal version of the Breuil-Mezard conjecture\, we develop an a
 lgorithm to compute arbitrarily close approximations of crystalline deform
 ation rings. Our approach\, based on reverse-engineering the Taylor-Wiles-
 Kisin patching method\, aims to provide detailed insights into these rings
  and their structural properties\, at least conjecturally.\n\npre-talk at 
 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/133/
END:VEVENT
BEGIN:VEVENT
SUMMARY:John Voight (Sydney)
DTSTART:20250123T000000Z
DTEND:20250123T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/134
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/134
 /">Hilbert modular forms obtained from orthogonal modular forms on quatern
 ary lattices</a>\nby John Voight (Sydney) as part of UCSD number theory se
 minar\n\nLecture held in APM 7321 and online.\n\nAbstract\nWe make explici
 t the relationship between Hilbert modular forms and orthogonal modular fo
 rms arising from positive definite quaternary lattices over the ring of in
 tegers of a totally real number field.  Our work uses the Clifford algebra
 \, and it generalizes that of Ponomarev\, Bocherer--Schulze-Pillot\, and o
 thers by allowing for general discriminant\, weight\, and class group of t
 he base ring.  This is joint work with Eran Assaf\, Dan Fretwell\, Colin I
 ngalls\, Adam Logan\, and Spencer Secord.\n\npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/134/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Masato Wakayama (Kyushu)
DTSTART:20250130T000000Z
DTEND:20250130T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/135
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/135
 /">Quantum interactions and number theory</a>\nby Masato Wakayama (Kyushu)
  as part of UCSD number theory seminar\n\nLecture held in APM 7321 and onl
 ine.\n\nAbstract\nQuantum interaction models discussed here are the (asymm
 etric) quantum Rabi\nmodel (QRM) and non-commutative harmonic oscillator (
 NCHO). The QRM is the most fun-\ndamental model describing the interaction
  between a photon and two-level atoms. The NCHO\ncan be considered as a co
 vering model of the QRM\, and recently\, the eigenvalue problems of\nNCHO 
 and two-photon QRM (2pQRM) are shown to be equivalent. Spectral degeneracy
  can\noccur in models\, but correspondingly there is a hidden symmetry rel
 ates geometrical nature\ndescribed by hyperelliptic curves. In addition\, 
 the analytical formula for the heat kernel (prop-\nagator)/partition funct
 ion of the QRM is described as a discrete path integral and gives the\nmer
 omorphic continuation of its spectral zeta function (SZF). This discrete p
 ath integral can\nbe interpreted to the irreducible decomposition of the i
 nfinite symmetric group $\\mathfrak{S}_\\infty$ naturally acting on $\\mat
 hbb{F}_2^\\infty$\, $\\mathbb{F}_2$ being the binary field. Moreover\, fro
 m the special values of the SZF of NCHO\, an analogue of the Apéry number
 s is naturally appearing\, and their generating functions are\, e.g.\, giv
 en by modular forms\, Eichler integrals of a congruence subgroup. The talk
  overviews those above and present questions which are open.\n\npre-talk a
 t 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/135/
END:VEVENT
BEGIN:VEVENT
SUMMARY:A. Raghuram (Fordham)
DTSTART:20250206T000000Z
DTEND:20250206T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/136
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/136
 /">Congruences and the special values of L-functions</a>\nby A. Raghuram (
 Fordham) as part of UCSD number theory seminar\n\nLecture held in APM 7321
  and online.\n\nAbstract\nThere is an idea in number theory that if two ob
 jects are congruent modulo a prime p\, then the congruence can also be see
 n for the special values of L-functions attached to the objects. Here is a
  context explicating this idea: Suppose f and f' are holomorphic cuspidal 
 eigenforms of weight k and level N\, and suppose f is congruent to f' modu
 lo p\; suppose g is another cuspidal eigenform of weight l\; if the differ
 ence k - l is large then the Rankin-Selberg L-function L(s\, f x g) has en
 ough critical points\; same for L(s\, f' x g)\; one expects then that ther
 e is a congruence modulo p between the algebraic parts of L(m\, f x g) and
  L(m\, f' x g) for any critical point m. In this talk\, after elaborating 
 on this idea\, I will describe the results of some computational experimen
 ts where one sees such congruences for ratios of critical values for Ranki
 n-Selberg L-functions. Towards the end of my talk\, time-permitting\, I wi
 ll sketch a framework involving Eisenstein cohomology for GL(4) over Q whi
 ch will permit us to prove such congruences. This is joint work with my st
 udent P. Narayanan.\n\npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/136/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Santiago Arango-Piñeros (Emory)
DTSTART:20250213T000000Z
DTEND:20250213T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/137
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/137
 /">Counting 5-isogenies of elliptic curves over the rationals</a>\nby Sant
 iago Arango-Piñeros (Emory) as part of UCSD number theory seminar\n\nLect
 ure held in APM 7321 and online.\n\nAbstract\nIn collaboration with Han\, 
 Padurariu\, and Park\, we show that the number of $5$-isogenies of ellipti
 c curves defined over $\\mathbb{Q}$ with naive height bounded by $H > 0$ i
 s asymptotic to $C_5\\cdot H^{1/6} (\\log H)^2$ for some explicitly comput
 able constant $C_5 > 0$. This settles the asymptotic count of rational poi
 nts on the genus zero modular curves $X_0(m)$. We leverage an explicit $\\
 mathbb{Q}$-isomorphism between the stack $\\mathscr{X}_0(5)$ and the gener
 alized Fermat equation $x^2 + y^2 = z^4$ with $\\mathbb{G}_m$ action of we
 ights $(4\, 4\, 2)$.\n\nPretalk: I will explain how to count isomorphism c
 lasses of elliptic curves over the rationals. On the way\, I will introduc
 e some basic stacky notions: torsors\, quotient stacks\, weighted projecti
 ve stacks\, and canonical rings.\n\npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/137/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Marie-France Vigneras (Jussieu)
DTSTART:20250313T210000Z
DTEND:20250313T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/139
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/139
 /">Asymptotics of $p$-adic groups\, mostly $SL_2$ [Colloquium]</a>\nby Mar
 ie-France Vigneras (Jussieu) as part of UCSD number theory seminar\n\nLect
 ure held in APM 6402.\n\nAbstract\nLet $p$ be a prime number and $ Q_p$  t
 he field  of $p$-adic numbers.\n The  representations of  a cousin of  the
  Galois  group  of an algebraic closure of $ Q_p$ are related  (the {\\bf 
 Langlands's bridge}) to the representations of reductive $p$-adic groups\,
  for instance  $SL_2(Q_p)\,  GL_n(Q_p) $.   The   irreducible  representat
 ions $\\pi$ of reductive $p$-adic groups are  easier  to study than those 
 of the  Galois groups but they are rarely finite dimensional. Their classi
 fication is  very involved but \n  their behaviour  around the identity\, 
 that we call the ``asymptotics'' of $\\pi$\, are expected to be more unifo
 rm. We shall survey what is known  (joint work with Guy Henniart)\, and wh
 at it suggests.\n\nColloquium\, no livestream\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/139/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Koji Shimizu and Gyujin Oh (Tsinghua/Columbia)
DTSTART:20250206T220000Z
DTEND:20250206T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/140
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/140
 /">Moduli stack of isocrystals and counting local systems</a>\nby Koji Shi
 mizu and Gyujin Oh (Tsinghua/Columbia) as part of UCSD number theory semin
 ar\n\nLecture held in APM 6402 and online.\n\nAbstract\nTo a smooth projec
 tive curve over a finite field\, we associate rigid-analytic moduli stacks
  of isocrystals together with the Verschiebung endomorphism. We develop re
 levant foundations of rigid-analytic stacks\, and discuss the examples and
  properties of such moduli stacks. We also illustrate how such moduli can 
 be used to count p-adic coefficient objects on the curve of rank one.\n\nT
 he main talk will be given by Oh. In the pre-talk\, Shimizu will introduce
  integrable connections and isocrystals\, which will be the key objects in
  the main talk.\n\npre-talk at 1pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/140/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zeyu Liu (UC Berkeley)
DTSTART:20250220T000000Z
DTEND:20250220T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/141
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/141
 /">A stacky approach to prismatic crystals</a>\nby Zeyu Liu (UC Berkeley) 
 as part of UCSD number theory seminar\n\nLecture held in APM 7321 and onli
 ne.\n\nAbstract\nNowadays prismatic crystals are gathering an increasing i
 nterest as they unify various coefficients in $p$-adic cohomology theories
 . Recently\, attached to any $p$-adic formal scheme $X$\, Drinfeld and Bha
 tt-Lurie constructed certain ring stacks\, including the prismatization of
  $X$\, on which quasi-coherent complexes correspond to various crystals on
  the prismatic site of $X$. While such a stacky approach sheds some new li
 ght on studying prismatic crystals\, little is known outside of the Hodge-
 Tate locus. In this talk\, we will introduce our recent work on studying q
 uasi-coherent complexes on the prismatization of $X$ via various charts.\n
 \npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/141/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Arijit Chakraborty (UC San Diego)
DTSTART:20250116T000000Z
DTEND:20250116T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/142
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/142
 /">A Power-Saving Error Term in Counting C2 ≀ H Number Fields</a>\nby Ar
 ijit Chakraborty (UC San Diego) as part of UCSD number theory seminar\n\nL
 ecture held in APM 7321 and online.\n\nAbstract\nOne of the central proble
 ms in Arithmetic Statistics is counting number field extensions of a fixed
  degree with a given Galois group\, parameterized by discriminants. This t
 alk focuses on C2 ≀ H extensions over an arbitrary base field. While Jü
 rgen Klüners has established the main term in this setting\, we present a
 n alternative approach that provides improved power-saving error terms for
  the counting function.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/142/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Keegan Ryan (UC San Diego)
DTSTART:20250306T000000Z
DTEND:20250306T010000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/143
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/143
 /">Solving Multivariate Coppersmith Problems with Known Moduli</a>\nby Kee
 gan Ryan (UC San Diego) as part of UCSD number theory seminar\n\nLecture h
 eld in APM 7321 and online.\n\nAbstract\nA central problem in cryptanalysi
 s involves computing the set of solutions within a bounded region to syste
 ms of modular multivariate polynomials. Typical approaches to this problem
  involve identifying shift polynomials\, or polynomial combinations of inp
 ut polynomials\, with good computational properties. In particular\, we ca
 re about the size of the support of the shift polynomials\, the degree of 
 each monomial in the support\, and the magnitude of coefficients. While sh
 ift polynomials for systems of a single modular univariate polynomial have
  been well understood since Coppersmith's original 1996 work\, multivariat
 e systems have been more difficult to analyze. Most analyses of shift poly
 nomials only apply to specific problem instances\, and it has long been a 
 goal to find a general method for constructing shift polynomials for any s
 ystem of modular multivariate polynomials. In recent work\, we have made p
 rogress toward this goal by applying Groebner bases\, graph optimization a
 lgorithms\, and Ehrhart's theory of polytopes to this problem. This talk f
 ocuses on these mathematical aspects as they relate to our work\, as well 
 as open conjectures about the asymptotic performance of our strategies.\n\
 npre-talk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/143/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jake Huryn (Ohio State)
DTSTART:20250402T230000Z
DTEND:20250403T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/144
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/144
 /">Geometric properties of the "tautological" local systems on Shimura var
 ieties</a>\nby Jake Huryn (Ohio State) as part of UCSD number theory semin
 ar\n\nLecture held in APM 7321 and online.\n\nAbstract\nSome Shimura varie
 ties are moduli spaces of Abelian varieties with extra structure.\nThe Tat
 e module of a universal Abelian variety is a natural source of $\\ell$-adi
 c local systems on such Shimura varieties. Remarkably\, the theory allows 
 one to build these local systems intrinsically from the Shimura variety in
  an essentially tautological way\, and this construction can be carried ou
 t in exactly the same way for Shimura varieties whose moduli interpretatio
 n remains conjectural.\n\nThis suggests the following program: Show that t
 hese tautological local systems "look as if" they were arising from the co
 homology of geometric objects. In this talk\, I will describe some recent 
 progress. It is based on joint work with Kiran Kedlaya\, Christian Klevdal
 \, and Stefan Patrikis\, as well as joint work with Yifei Zhang.\n\npre-ta
 lk at 3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/144/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joe Kramer-Miller (Lehigh)
DTSTART:20250521T230000Z
DTEND:20250522T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/145
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/145
 /">On the diagonal and Hadamard grades of hypergeometric functions</a>\nby
  Joe Kramer-Miller (Lehigh) as part of UCSD number theory seminar\n\nLectu
 re held in APM 7321 and online.\n\nAbstract\nDiagonals of multivariate rat
 ional functions are an important class of functions arising in number theo
 ry\, algebraic geometry\, combinatorics\, and physics. For instance\, many
  hypergeometric functions are diagonals as well as the generating function
  for Apery's sequence. A natural question is to determine the diagonal gra
 de of a function\, i.e.\, the minimum number of variables one needs to exp
 ress a given function as a diagonal. The diagonal grade gives the ring of 
 diagonals a filtration. In this talk we study the notion of diagonal grade
  and the related notion of Hadamard grade (writing functions as the Hadama
 rd product of algebraic functions)\, resolving questions of Allouche-Mende
 s France\, Melczer\, and proving half of a conjecture recently posed by a 
 group of physicists. This work is joint with Andrew Harder.\n\npre-talk at
  3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/145/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Kristin Lauter (Meta)
DTSTART:20250430T220000Z
DTEND:20250430T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/146
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/146
 /">Using machine learning to solve hard math problems in practice (AWM col
 loquium)</a>\nby Kristin Lauter (Meta) as part of UCSD number theory semin
 ar\n\nLecture held in APM 6402.\n\nAbstract\nAI is taking off and we could
  say we are living in “the AI Era”.  Progress in AI today is based on 
 mathematics and statistics under the covers of machine learning models.  T
 his talk will explain recent work on AI4Crypto\, where we train AI models 
 to attack Post Quantum Cryptography (PQC) schemes based on lattices. I wil
 l use this work as a case study in training ML models to solve hard math p
 roblems in practice.  Our AI4Crypto project has developed AI models capabl
 e of recovering secrets in post-quantum cryptosystems (PQC).  The standard
 ized PQC systems were designed to be secure against a quantum computer\, b
 ut are not necessarily safe against advanced AI!  \n\nUnderstanding the co
 ncrete security of these standardized PQC schemes is important for the fut
 ure of e-commerce and internet security.  So instead of saying that we are
  living in a “Post-Quantum” era\, we should say that we are living in 
 a “Post-AI” era!\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/146/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Hannah Larson (UC Berkeley)
DTSTART:20250516T230000Z
DTEND:20250517T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/147
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/147
 /">Moduli spaces of curves with polynomial point count (AG seminar)</a>\nb
 y Hannah Larson (UC Berkeley) as part of UCSD number theory seminar\n\nLec
 ture held in APM 7321.\n\nAbstract\nHow many isomorphism classes of genus 
 g curves are there over a finite field $\\mathbb{F}_q$? In joint work with
  Samir Canning\, Sam Payne\, and Thomas Willwacher\, we prove that the ans
 wer is a polynomial in q if and only if g is at most 8. One of the key ing
 redients is our recent progress on understanding low-degree odd cohomology
  of moduli spaces of stable curves with marked points.\n\npre-talk at 3:30
 pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/147/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jize Yu (Rice)
DTSTART:20251105T220000Z
DTEND:20251105T230000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/148
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/148
 /">Towards a tamely ramified local geometric Langlands correspondence for 
 p-adic groups</a>\nby Jize Yu (Rice) as part of UCSD number theory seminar
 \n\nLecture held in APM 7321.\n\nAbstract\nFor a reductive $p$-adic group 
 $G$\, Kazhdan-Lusztig prove an isomorphism of the the extended affine Heck
 e algebra and the $G^\\vee$-equivariant $K$-group of the Steinberg variety
  of the Langlands dual group $G^\\vee$. It has a profound application of p
 roving an important case of the local Langlands correspondence which is kn
 own as the Deligne-Langlands conjecture. For $G$ being a reductive group o
 ver an equal-characteristic local field\, Bezrukavnikov upgrades Kazhdan-L
 usztig's isomorphism to an equivalence of monoidal categories and proves t
 he tamely ramified local geometric Langlands correspondence. In this talk\
 , we discuss an ongoing project with João Lourenço on proving a tamely r
 amified local geometric Langlands correspondence for reductive $p$-adic gr
 oups. Time permitting\, I will mention an interesting variant of Bezrukavn
 ikov's equivalence in Ben-Zvi-Sakellaridis-Venkatesh's framework of the re
 lative Langlands program based on a joint work in preparation with Milton 
 Lin and Toan Pham.\n\npre-talk at 1:20pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/148/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jasmine Camero (Emory)
DTSTART:20251029T210000Z
DTEND:20251029T220000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/150
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/150
 /">Classifying Possible Density Degree Sets of Hyperelliptic Curves</a>\nb
 y Jasmine Camero (Emory) as part of UCSD number theory seminar\n\nLecture 
 held in APM 7321.\n\nAbstract\nLet $C$ be a smooth\, projective\, geometri
 cally integral hyperelliptic curve of genus $g \\geq 2$ over a number fiel
 d $k$. To study the distribution of degree $d$ points on $C$\, we introduc
 e the notion of $\\mathbb{P}^1$- and AV-parameterized points\, which arise
  from natural geometric constructions. These provide a framework for class
 ifying density degree sets\, an important invariant of a curve that record
 s the degrees $d$ for which the set of degree $d$ points on $C$ is Zariski
  dense. Zariski density has two geometric sources: If $C$ is a degree $d$ 
 cover of $\\mathbb{P}^1$ or an elliptic curve $E$ of positive rank\, then 
 pulling back rational points on $\\mathbb{P}^1$ or $E$ give an infinite fa
 mily of degree $d$ points on $C$. Building on this perspective\, we give a
  classification of the possible density degree sets of hyperelliptic curve
 s.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/150/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wei Yao (U. Chicago)
DTSTART:20260401T230000Z
DTEND:20260402T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/151
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/151
 /">$p$-adic height pairing using $K_2$-class field theory and Galois-value
 d heights</a>\nby Wei Yao (U. Chicago) as part of UCSD number theory semin
 ar\n\nLecture held in APM 7321.\n\nAbstract\nIn this talk\, I will constru
 ct a $p$-adic height pairing for curves with split degenerate stable reduc
 tion over a prime $p$ using the higher class field theory of Kato-Saito. T
 his pairing can be shown to coincide with the standard Coleman-Gross heigh
 t pairing when extended to the semistable reduction case using methods by 
 Besser and Vologodsky. At the end\, I will briefly mention how this new me
 thod inspires the definition of a height pairing valued in certain Galois 
 groups related to the function field of the original curve.\n\npre-talk at
  3pm\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/151/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ben Church (Stanford)
DTSTART:20260603T230000Z
DTEND:20260604T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/152
DESCRIPTION:by Ben Church (Stanford) as part of UCSD number theory seminar
 \n\nLecture held in APM 7321.\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/152/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Everett Howe (unaffiliated)
DTSTART:20260506T230000Z
DTEND:20260507T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/153
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/UCSD_NTS/153
 /">Curves of genus 2 with maps of every degree to a fixed elliptic curve</
 a>\nby Everett Howe (unaffiliated) as part of UCSD number theory seminar\n
 \nLecture held in APM 7321.\n\nAbstract\nWe show that up to isomorphism th
 ere are exactly twenty pairs $(C\, E)$\, where $C$ is a genus-2 curve over
  the complex numbers\, where $E$ is an elliptic curve over the complex num
 bers\, and where for every integer $n > 1$ there is a map of degree $n$ fr
 om $C$ to $E$. For example\, if $C$ is the curve $y^2 = x^5 + 5 x^3 + 5 x$
 \, and if $E$ is an elliptic curve with CM by the order of discriminant -2
 0\, then $(C\, E)$ is such a pair.\n\nOn the other hand\, we produce some 
 finite sets $S$ of integers such that if $C$ is a genus-2 curve in charact
 eristic 0\, and if for every $n$ in $S$ there is an elliptic curve $E_n$ a
 nd a degree-$n$ map $\\phi_n$ from $C$ to $E_n$\, then for at least one of
  these $n$\, the map $\\phi_n$ factors through a nontrivial isogeny.\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/153/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jennifer Balakrishnan (Boston U.)
DTSTART:20260512T230000Z
DTEND:20260513T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/154
DESCRIPTION:by Jennifer Balakrishnan (Boston U.) as part of UCSD number th
 eory seminar\n\nLecture held in APM 7321.\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/154/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brandon Alberts (Eastern Michigan U.)
DTSTART:20260520T230000Z
DTEND:20260521T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/155
DESCRIPTION:by Brandon Alberts (Eastern Michigan U.) as part of UCSD numbe
 r theory seminar\n\nLecture held in APM 7321.\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/155/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nikolas Castro (UC San Diego)
DTSTART:20260527T230000Z
DTEND:20260528T000000Z
DTSTAMP:20260422T225829Z
UID:UCSD_NTS/156
DESCRIPTION:by Nikolas Castro (UC San Diego) as part of UCSD number theory
  seminar\n\nLecture held in APM 7321.\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UCSD_NTS/156/
END:VEVENT
END:VCALENDAR
