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BEGIN:VEVENT
SUMMARY:Renzo Cavalieri (Colorado State University)
DTSTART;VALUE=DATE-TIME:20200925T153000Z
DTEND;VALUE=DATE-TIME:20200925T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/1
DESCRIPTION:Title: T
ropical Psi Classes\nby Renzo Cavalieri (Colorado State University) as
part of UBC Vancouver Algebraic Geometry Seminar\n\nAbstract: TBA\n
LOCATION:https://researchseminars.org/talk/UBC-AG/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pierrick Bousseau (ETH Zürich)
DTSTART;VALUE=DATE-TIME:20201002T153000Z
DTEND;VALUE=DATE-TIME:20201002T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/2
DESCRIPTION:Title: T
he skein algebra of the 4-punctured sphere from curve counting\nby Pie
rrick Bousseau (ETH Zürich) as part of UBC Vancouver Algebraic Geometry S
eminar\n\n\nAbstract\nThe Kauffman bracket skein algebra is a quantization
of the algebra of regular functions on the SL_2 character variety of a to
pological surface. I will explain how to realize the skein algebra of the
4-punctured sphere as the output of a mirror symmetry construction based o
n higher genus Gromov-Witten invariants of a log Calabi-Yau cubic surface.
This leads to a proof of a previously conjectured positivity property of
the bracelets bases of the skein algebras of the 4-punctured sphere and of
the 1-punctured torus.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tony Yue Yu (Université Paris-Sud\, Paris-Saclay)
DTSTART;VALUE=DATE-TIME:20201009T153000Z
DTEND;VALUE=DATE-TIME:20201009T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/3
DESCRIPTION:Title: S
econdary fan\, theta functions and moduli of Calabi-Yau pairs\nby Tony
Yue Yu (Université Paris-Sud\, Paris-Saclay) as part of UBC Vancouver Al
gebraic Geometry Seminar\n\n\nAbstract\nWe conjecture that any connected c
omponent Q of the moduli space of triples (X\,E=E1+⋯+En\,Θ) where X is
a smooth projective variety\, E is a normal crossing anti-canonical diviso
r with a 0-stratum\, every Ei is smooth\, and Θ is an ample divisor not c
ontaining any 0-stratum of E\, is \\emph{unirational}. More precisely: not
e that Q has a natural embedding into the Kollár-Shepherd-Barron-Alexeev
moduli space of stable pairs\, we conjecture that its closure admits a fin
ite cover by a complete toric variety. We construct the associated complet
e toric fan\, generalizing the Gelfand-Kapranov-Zelevinski secondary fan f
or reflexive polytopes. Inspired by mirror symmetry\, we speculate a synth
etic construction of the universal family over this toric variety\, as the
Proj of a sheaf of graded algebras with a canonical basis\, whose structu
re constants are given by counts of non-archimedean analytic disks. In the
Fano case and under the assumption that the mirror contains a Zariski ope
n torus\, we construct the conjectural universal family\, generalizing the
families of Kapranov-Sturmfels-Zelevinski and Alexeev in the toric case.
In the case of del Pezzo surfaces with an anti-canonical cycle of (−1)-c
urves\, we prove the full conjecture. The reference is arXiv:2008.02299 jo
int with Hacking and Keel.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yan Soibelman (Kansas State University)
DTSTART;VALUE=DATE-TIME:20201016T153000Z
DTEND;VALUE=DATE-TIME:20201016T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/4
DESCRIPTION:Title: E
xponential integrals\, Holomorphic Floer theory and resurgence\nby Yan
Soibelman (Kansas State University) as part of UBC Vancouver Algebraic Ge
ometry Seminar\n\n\nAbstract\nHolomorphic Floer theory is a joint project
with Maxim Kontsevich\, which is devoted to various aspects of the Floer t
heory in the framework of complex symplectic manifolds.\n\nIn my talk I wi
ll consider an important special case of the general story. Exponential i
ntegrals in finite and infinite dimension can be thought of generalization
of the theory of periods (i.e variations of Hodge structure). In particu
lar\, there are comparison isomorphisms between Betti and de Rham cohomolo
gy in the exponential setting. These isomorphisms are corollaries of categ
orical equivalences which are incarnations of our generalized Riemann-Hilb
ert correspondence for complex symplectic manifolds.\n\nFurthermore\, foma
l series which appear e.g. in the stationary phase method or Feynman expan
sions (in infinite dimensions) are Borel re-summable (resurgent). If time
permits I will explain the underlying mathematical structure which we call
analytic wall-crossing structure. From the perspective of Holomorphic Flo
er theory it is related to the estimates for the number of pseudo-holomorp
hic discs with boundaries on two given complex Lagrangian submanifolds.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dragos Oprea (UCSD)
DTSTART;VALUE=DATE-TIME:20201023T153000Z
DTEND;VALUE=DATE-TIME:20201023T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/5
DESCRIPTION:Title: V
irtual invariants of Quot schemes of surfaces\nby Dragos Oprea (UCSD)
as part of UBC Vancouver Algebraic Geometry Seminar\n\n\nAbstract\nThe Quo
t schemes of surfaces parametrizing quotients of dimension at most 1 of th
e trivial sheaf carry 2-term perfect obstruction theories. Several generat
ing series of associated virtual invariants are conjectured to be given by
rational functions. We show this is the case for several geometries inclu
ding all smooth projective surfaces with p_g>0. This talk is based on join
t work with Noah Arbesfeld\, Drew Johnson\, Woonam Lim and Rahul Pandharip
ande.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniel Halpern-Leistner (Cornell University)
DTSTART;VALUE=DATE-TIME:20201030T153000Z
DTEND;VALUE=DATE-TIME:20201030T170000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/6
DESCRIPTION:Title: D
erived Theta-stratifications and the D-equivalence conjecture\nby Dani
el Halpern-Leistner (Cornell University) as part of UBC Vancouver Algebrai
c Geometry Seminar\n\n\nAbstract\nThe D-equivalence conjecture predicts th
at birationally equivalent projective Calabi-Yau manifolds have equivalent
derived categories of coherent sheaves. It is motivated by homological mi
rror symmetry\, and has inspired a lot of recent work on connections betwe
en birational geometry and derived categories. In dimension 3\, the conjec
ture is settled\, but little is known in higher dimensions. I will discuss
a proof of this conjecture for the class of Calab-Yau manifolds that are
birationally equivalent to some moduli space of stable sheaves on a K3 sur
face. This is the only class for which the conjecture is known in dimensio
n >3. The proof uses a more general structure theory for the derived categ
ory of an algebraic stack equipped with a Theta-stratification\, which we
apply in this case to the Harder-Narasimhan stratification of the moduli o
f sheaves.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yifeng Huang (University of Michigan)
DTSTART;VALUE=DATE-TIME:20201106T170000Z
DTEND;VALUE=DATE-TIME:20201106T180000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/7
DESCRIPTION:Title: C
ohomology of configuration spaces of punctured varieties\nby Yifeng Hu
ang (University of Michigan) as part of UBC Vancouver Algebraic Geometry S
eminar\n\n\nAbstract\nGiven a smooth complex variety $X$ (not necessarily
compact)\, consider the unordered configuration space $Conf^n(X)$ defined
as ${(x_1\,...\,x_n)\\in X^n: x_i \\neq x_j\\ \\text{for}\\ i\\neq j} / S_
n$. The singular cohomology of $Conf^n(X)$ has long been an active area of
research. In this talk\, we investigate the following phenomenon: "punctu
ring once more" seems to have a very predictable effect on the cohomology
of configuration spaces when the variety we start with is noncompact. In s
pecific\, a formula of Napolitano determines the Betti numbers of $Conf^n(
X - {P})$ from the Betti numbers of $Conf^m(X)$ $(m \\leq n)$ if $X$ is a
smooth *noncompact* algebraic curve and $P$ is a point. We present a new p
roof using an explicit algebraic method\, which also upgrades this formula
about Betti numbers into a formula about mixed Hodge numbers and generali
zes this formula to certain cases where $X$ is of higher dimension.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Emily Clader (San Francisco State University)
DTSTART;VALUE=DATE-TIME:20201120T170000Z
DTEND;VALUE=DATE-TIME:20201120T180000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/8
DESCRIPTION:Title: P
ermutohedral Complexes and Curves With Cyclic Action\nby Emily Clader
(San Francisco State University) as part of UBC Vancouver Algebraic Geomet
ry Seminar\n\n\nAbstract\nAlthough the moduli space of genus-zero curves i
s not a toric\nvariety\, it shares an intriguing amount of the combinatori
al structure that a\ntoric variety would enjoy. In fact\, by adjusting the
moduli problem slightly\,\none finds a moduli space that is indeed toric\
, known as Losev-Manin space. The\nassociated polytope is the permutohedro
n\, which also encodes the\ngroup-theoretic structure of the symmetric gro
up. Batyrev and Blume generalized\nthis story by constructing a "type-B" v
ersion of Losev-Manin space\, whose\nassociated polytope is a signed permu
tohedron that relates to the group of\nsigned permutations. In joint work
in progress with C. Damiolini\, D. Huang\, S.\nLi\, and R. Ramadas\, we ca
rry out the next stage of generalization\, defining a\nfamily of moduli sp
ace of curves with Z_r action encoded by an associated\n"permutohedral com
plex" for a more general complex reflection group\, which\nspecializes whe
n r=2 to Batyrev and Blume's moduli space.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dustin Ross (San Francisco State University)
DTSTART;VALUE=DATE-TIME:20201127T170000Z
DTEND;VALUE=DATE-TIME:20201127T180000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/9
DESCRIPTION:Title: P
utting the "volume" back in volume polynomials\nby Dustin Ross (San Fr
ancisco State University) as part of UBC Vancouver Algebraic Geometry Semi
nar\n\n\nAbstract\nIt is a strange and wonderful fact that Chow rings of m
atroids behave in many ways similarly to Chow rings of smooth projective v
arieties. Because of this\, the Chow ring of a matroid is determined by a
homogeneous polynomial called its volume polynomial\, whose coefficients r
ecord the degrees of all possible top products of divisors. The use of the
word "volume" is motivated by the fact that the volume polynomial of a sm
ooth projective toric variety actually measures the volumes of certain pol
ytopes associated to the variety. In the matroid setting\, on the other ha
nd\, no such polytopes exist\, and the goal of our work was to find more g
eneral polyhedral objects whose volume is measured by the volume polynomia
l of matroids. In this talk\, I will motivate and describe these polyhedra
l objects. This is joint work with Anastasia Nathanson.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Junliang Shen (MIT)
DTSTART;VALUE=DATE-TIME:20201204T163000Z
DTEND;VALUE=DATE-TIME:20201204T173000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/10
DESCRIPTION:Title:
Intersection cohomology of the moduli of of 1-dimensional sheaves and the
moduli of Higgs bundles\nby Junliang Shen (MIT) as part of UBC Vancouv
er Algebraic Geometry Seminar\n\n\nAbstract\nIn general\, the topology of
the moduli space of semistable sheaves on an algebraic variety relies heav
ily on the choice of the Euler characteristic of the sheaves. We show a st
riking phenomenon that\, for the moduli of 1-dimensional semistable sheave
s on a toric del Pezzo surface (e.g. P^2) or the moduli of semistable Higg
s bundles with respect to a divisor of degree > 2g-2 on a curve\, the inte
rsection cohomology of the moduli space is independent of the choice of th
e Euler characteristic. This confirms a conjecture of Bousseau for P^2\,
and proves a conjecture of Toda in the case of local toric Calabi-Yau 3-fo
lds. In the proof\, a generalized version of Ngô's support theorem plays
a crucial role. Based on joint work in progress with Davesh Maulik.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christopher Woodward (Rutgers University)
DTSTART;VALUE=DATE-TIME:20201113T163000Z
DTEND;VALUE=DATE-TIME:20201113T173000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/11
DESCRIPTION:Title:
Quantum K-theory of git quotients\nby Christopher Woodward (Rutgers Un
iversity) as part of UBC Vancouver Algebraic Geometry Seminar\n\n\nAbstrac
t\n(w E. Gonzalez) I will discuss a generalization of the Kirwan map to q
uantum K-theory\, a presentation of quantum K-theory of toric varieties\,
and some open questions.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ming Zhang (UBC)
DTSTART;VALUE=DATE-TIME:20201113T174500Z
DTEND;VALUE=DATE-TIME:20201113T184500Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/13
DESCRIPTION:Title:
Verlinde/Grassmannian Correspondence\nby Ming Zhang (UBC) as part of U
BC Vancouver Algebraic Geometry Seminar\n\n\nAbstract\nIn the 90s'\, Witte
n gave a physical derivation of an isomorphism between the Verlinde algebr
a of $\\mathrm{GL}(n)$ of level l and the quantum cohomology ring of the G
rassmannian $\\mathrm{Gr}(n\,n+l)$. In the joint work arXiv:1811.01377 wit
h Yongbin Ruan\, we proposed a $K$-theoretic generalization of Witten's wo
rk by relating the $\\mathrm{GL}_n$ Verlinde numbers to the level $l$ quan
tum $K$-invariants of the Grassmannian $\\mathrm{Gr}(n\,n+l)$\, and refer
to it as the Verlinde/Grassmannian correspondence. The correspondence was
formulated precisely in the aforementioned paper\, and we proved the rank
2 case ($n$=2) there.\n\nIn this talk\, I will first explain the backgroun
d of this correspondence and its interpretation in physics. Then I will di
scuss the main idea of the proof for arbitrary rank. A new technical ingre
dient is the virtual nonabelian localization formula developed by Daniel H
alpern-Leistner.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Henry Liu (Columbia University)
DTSTART;VALUE=DATE-TIME:20210201T230000Z
DTEND;VALUE=DATE-TIME:20210202T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/14
DESCRIPTION:Title:
Quasimaps and stable pairs\nby Henry Liu (Columbia University) as part
of UBC Vancouver Algebraic Geometry Seminar\n\n\nAbstract\nI will explain
an equivalence between a flavor of Donaldson-Thomas theory (due to Bryan
and Steinberg) on ADE surface fibrations and quasimaps to Hilbert schemes
of ADE surfaces. The proof involves an explicit combinatorial description
of vertices. The equivalence can be used to relate machinery from both sid
es\, notably an equivariant K-theoretic DT crepant resolution conjecture a
nd 3d mirror symmetry.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Qile Chen (Boston College)
DTSTART;VALUE=DATE-TIME:20210322T220000Z
DTEND;VALUE=DATE-TIME:20210322T230000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/15
DESCRIPTION:Title:
Counting curves in critical locus via logarithmic compactifications\nb
y Qile Chen (Boston College) as part of UBC Vancouver Algebraic Geometry S
eminar\n\n\nAbstract\nI will introduce some recent developments and work i
n progress on\nstudying Gauged Linear Sigma Models using logarithmic compa
ctifications.\n\nThese logarithmic compactifications admit two types of vi
rtual cycles ---\nthe reduced virtual cycles that recover Gromov-Witten in
variants of\ncomplete intersections\, and the canonical virtual cycles th
at depend only\non the geometry of ambient spaces. These two types of virt
ual cycles differ\nonly by a third virtual cycle of the boundary of the lo
garithmic\ncompactifications. Using the punctured logarithmic maps of\nAbr
amovich-Chen-Gross-Siebert\, these virtual cycles can be computed via the\
ntropical and equivariant geometry of the logarithmic compactifications.\n
This leads to a new method for computing Gromov-Witten invariants of\ncomp
lete intersections.\n\nThe talk consists of joint work with Felix Janda\,
Yongbin Ruan\, Adrien\nSauvaget and Rachel Webb.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jack Petok (Dartmouth College)
DTSTART;VALUE=DATE-TIME:20210315T220000Z
DTEND;VALUE=DATE-TIME:20210315T230000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/16
DESCRIPTION:Title:
Kodaira dimensions of some moduli spaces of hyperkähler fourfolds\nby
Jack Petok (Dartmouth College) as part of UBC Vancouver Algebraic Geometr
y Seminar\n\n\nAbstract\nWe use modular forms to study the birational geom
etry of some moduli spaces of hyperkähler fourfolds. I'll review a bit of
the algebraic geometry of these moduli spaces\, and then I'll explain som
e methods\, due to Gritsenko\, Hulek\, and Sankaran\, for computing their
Kodaira dimensions. These methods make use of special modular forms define
d on high rank orthogonal groups. I'll also report on an ongoing project w
ith Jen Berg applying related techniques to certain moduli spaces of Enriq
ues surfaces.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dylan G.L. Allegretti (UBC)
DTSTART;VALUE=DATE-TIME:20210118T230000Z
DTEND;VALUE=DATE-TIME:20210119T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/17
DESCRIPTION:Title:
Wall-crossing and differential equations\nby Dylan G.L. Allegretti (UB
C) as part of UBC Vancouver Algebraic Geometry Seminar\n\n\nAbstract\nThe
Kontsevich-Soibelman wall-crossing formula describes the wall-crossing beh
avior of BPS invariants in Donaldson-Thomas theory. It can be formulated a
s an identity between (possibly infinite) products of automorphisms of a f
ormal power series ring. In this talk\, I will explain how these same prod
ucts also appear in the exact WKB analysis of Schrödinger's equation. In
this context\, they describe the Stokes phenomenon for objects known as Vo
ros symbols.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Arnav Tripathy (Harvard University)
DTSTART;VALUE=DATE-TIME:20210329T220000Z
DTEND;VALUE=DATE-TIME:20210329T230000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/18
DESCRIPTION:Title:
K3s as Hyperkahler Quotients\nby Arnav Tripathy (Harvard University) a
s part of UBC Vancouver Algebraic Geometry Seminar\n\n\nAbstract\nI'll exp
lain how to construct K3 surfaces as hyperkahler quotients and\, as time p
ermits\, our expected application to counting open GW invariants. This is
all joint work with M. Zimet.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yu-Wei Fan (UC Berkeley)
DTSTART;VALUE=DATE-TIME:20210208T230000Z
DTEND;VALUE=DATE-TIME:20210209T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/19
DESCRIPTION:Title:
Stokes matrices\, character varieties\, and points on spheres\nby Yu-W
ei Fan (UC Berkeley) as part of UBC Vancouver Algebraic Geometry Seminar\n
\n\nAbstract\nModuli spaces of points on n-spheres carry natural actions o
f braid groups. For n=0\,1\, and 3\, we prove that these symmetries extend
to actions of mapping class groups of positive genus surfaces\, through e
xceptional isomorphisms with certain character varieties. We also apply th
e exceptional isomorphisms to the study of Stokes matrices and exceptional
collections of triangulated categories. Joint work with Junho Peter Whang
.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mark Shoemaker (Colorado State University)
DTSTART;VALUE=DATE-TIME:20210222T230000Z
DTEND;VALUE=DATE-TIME:20210223T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/20
DESCRIPTION:Title:
A mirror theorem for gauged linear sigma models\nby Mark Shoemaker (Co
lorado State University) as part of UBC Vancouver Algebraic Geometry Semin
ar\n\n\nAbstract\nLet G be a finite group acting on a smooth complex varie
ty M. Let X —> M/G be a crepant resolution by a smooth variety X. The
Crepant Resolution Conjecture predicts a complicated relationship between
the Gromov—Witten invariants of X and the orbifold Gromov—Witten inva
riants of the stack [M/G].\n\nIn this talk I will describe an analogous co
njecture involving Landau—Ginzburg (LG) models. An LG model is\, roughl
y\, a smooth complex variety Y together with a regular function w: Y—> \
\CC. LG models can be used to give alternate “resolutions” of hypersu
rface singularities in a certain sense and are related to so-called noncom
mutative resolutions. I will briefly discuss the gauged linear sigma model
\, which is used to define curve counting invariants for LG models\, and d
escribe a new technique for computing these invariants.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Yefeng Shen (University of Oregon)
DTSTART;VALUE=DATE-TIME:20210301T230000Z
DTEND;VALUE=DATE-TIME:20210302T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/21
DESCRIPTION:Title:
Virasoro constraints in quantum singularity theory\nby Yefeng Shen (Un
iversity of Oregon) as part of UBC Vancouver Algebraic Geometry Seminar\n\
n\nAbstract\nIn this talk\, we introduce Virasoro operators in quantum sin
gularity theories for nondegenerate quasi-homogeneous polynomials with non
trivial diagonal symmetries. Using Givental's quantization formula of quad
ratic Hamiltonians\, these operators satisfy the Virasoro relations. Inspi
red by the famous Virasoro conjecture in Gromov-Witten theory\, we conject
ure that the genus g generating functions arise in quantum singularity the
ories are annihilated by the Virasoro operators. We verify the conjecture
in various examples and discuss the connections to mirror symmetry of LG m
odels and LG/CY correspondence. This talk is based on work joint with Weiq
iang He.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Davesh Maulik (MIT)
DTSTART;VALUE=DATE-TIME:20210308T230000Z
DTEND;VALUE=DATE-TIME:20210309T000000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/22
DESCRIPTION:Title:
Cohomology of the moduli of Higgs bundles and the Hausel-Thaddeus conjectu
re\nby Davesh Maulik (MIT) as part of UBC Vancouver Algebraic Geometry
Seminar\n\n\nAbstract\nIn this talk\, I will discuss some results on the
structure of the cohomology of the moduli space of stable SL_n Higgs bundl
es on a curve. One consequence is a new proof of the Hausel-Thaddeus conje
cture proven previously by Groechenig-Wyss-Ziegler via p-adic integration.
We will also discuss connections to the P=W conjecture if time permits. B
ased on joint work with Junliang Shen.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zijun Zhou (IPMU)
DTSTART;VALUE=DATE-TIME:20210412T220000Z
DTEND;VALUE=DATE-TIME:20210412T230000Z
DTSTAMP;VALUE=DATE-TIME:20240329T110025Z
UID:UBC-AG/23
DESCRIPTION:Title:
3d mirror symmetry\, vertex function\, and elliptic stable envelope\nb
y Zijun Zhou (IPMU) as part of UBC Vancouver Algebraic Geometry Seminar\n\
n\nAbstract\n3d mirror symmetry is a duality in physics\, where Higgs and
Coulomb branches of certain pairs of 3d N=4 SUSY gauge theories are exchan
ged with each other. Motivated from this\, M. Aganagic and A. Okounkov int
roduced the enumerative geometric conjecture that the vertex functions of
the mirror theories are related to each other. The two sets of q-differenc
e equations satisfied by the vertex functions\, in terms of the K\\"ahler
and equivariant parameters\, are expected to exchange with each other. The
conjecture therefore leads to a nontrivial relation between their monodro
my matrices\, the so-called elliptic stable envelopes. In this talk\, I wi
ll discuss the proof in several cases of the conjecture for both vertex fu
nctions and elliptic stable envelopes. This is based on joint works with R
. Rim\\'anyi\, A. Smirnov\, and A. Varchenko.\n
LOCATION:https://researchseminars.org/talk/UBC-AG/23/
END:VEVENT
END:VCALENDAR