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BEGIN:VEVENT
SUMMARY:Sasha Sodin (Queen Mary)
DTSTART;VALUE=DATE-TIME:20201112T203000Z
DTEND;VALUE=DATE-TIME:20201112T213000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/1
DESCRIPTION:Title: The Umpteen Operator\nby Sasha Sodin (Queen Mary) as part of UCI Math
ematical Physics\n\n\nAbstract\nIt was found in the 1990s that special lin
ear maps playing a role in the representation theory of the symmetric grou
p share common features with random matrices. We construct a representatio
n-theoretic operator which shares some properties with the Anderson model
(or\, perhaps\, with magnetic random Schroedinger operators)\, and show th
at indeed it boasts Lifshitz tails. The proof relies on a close connection
between the operator and the infinite board version of the fifteen puzzle
.\nNo background in the representation theory of the symmetric group will
be assumed. Based on joint work with Ohad Feldheim.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Mira Shamis (Queen Mary)
DTSTART;VALUE=DATE-TIME:20210114T200000Z
DTEND;VALUE=DATE-TIME:20210114T210000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/2
DESCRIPTION:Title: On the abominable properties of the Almost Mathieu operator with Liouvill
e frequencies\nby Mira Shamis (Queen Mary) as part of UCI Mathematical
Physics\n\n\nAbstract\nWe show that\, for sufficiently well approximable
frequencies\, several spectral characteristics of the Almost Mathieu opera
tor can be as poor as at all possible in the class of all discrete Schroed
inger operators. For example\, the modulus of continuity of the integrated
density of states may be no better than logarithmic. Other characteristic
s to be discussed are homogeneity\, the Parreau-Widom property\, and (for
the critical AMO) the Hausdorff content of the spectrum. Based on joint wo
rk with A. Avila\, Y. Last\, and Q. Zhou\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lingrui Ge (UCI)
DTSTART;VALUE=DATE-TIME:20210121T180000Z
DTEND;VALUE=DATE-TIME:20210121T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/3
DESCRIPTION:Title: Smooth quasiperiodic SL(2\,\\R)-cocycles (I)-Global rigidity results for
rotations reducibility and Last's intersection spectrum conjecture.\nb
y Lingrui Ge (UCI) as part of UCI Mathematical Physics\n\n\nAbstract\nFor
quasiperiodic Schr\\"odinger operators with one-frequency analytic potenti
als\, from dynamical systems side\, it has been proved that the correspond
ing quasiperiodic Schr\\"odinger cocycle is either rotations reducible or
has positive Lyapunov exponent for all irrational frequency and almost eve
ry energy by Avila-Fayad-Krikorian. From spectral theory side\, the ``Schr
\\"odinger conjecture" has been verified by Avila-Fayad-Krikorian and the
``Last's intersection spectrum conjecture" has been proved by Jitomirskay
a-Marx. The proofs of above results crucially depend on the analyticity of
the potentials. Is analyticity essential for those problems? Some open p
roblems in this aspect were raised by Fayad-Krikorian and Jitomirskaya-Ma
rx. In this paper\, we prove the above mentioned results for ultra-differe
ntiable potentials.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lingrui Ge (UCI)
DTSTART;VALUE=DATE-TIME:20210128T180000Z
DTEND;VALUE=DATE-TIME:20210128T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/4
DESCRIPTION:Title: Smooth quasiperiodic SL(2\,\\R)-cocycles (II)-Sharp transition space for
the continuity of the Lyapunov exponent.\nby Lingrui Ge (UCI) as part
of UCI Mathematical Physics\n\n\nAbstract\nWe construct points of disconti
nuity of the Lyapunov exponent of quasiperiodic Shr\\"odinger cocycles in
Gevrey space $G^{s}$ with $s>2$. In contrast\, the Lyapunov exponent has b
een proved to be continuous in $G^{s}$ with $s<2$ by Klein and Cheng-Ge-Yo
u-Zhou. This shows that $G^2$ is the transition space for the continuity o
f the Lyapunov exponent.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Lingrui Ge (UCI)
DTSTART;VALUE=DATE-TIME:20210204T180000Z
DTEND;VALUE=DATE-TIME:20210204T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/5
DESCRIPTION:by Lingrui Ge (UCI) as part of UCI Mathematical Physics\n\nAbs
tract: TBA\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Wencai Liu (Texas A&M)
DTSTART;VALUE=DATE-TIME:20210211T180000Z
DTEND;VALUE=DATE-TIME:20210211T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/6
DESCRIPTION:Title: Irreducibility of the Fermi variety for discrete periodic Schr\\"odinger
operators\nby Wencai Liu (Texas A&M) as part of UCI Mathematical Physi
cs\n\n\nAbstract\nLet $H_0$ be a discrete periodic Schr\\"odinger operato
r on $\\Z^d$:\n\n$$H_0=-\\Delta+V\,$$ where $\\Delta$ is the discrete Lapl
acian and $V:\\Z^d\\to \\R$ is periodic. We prove that for any $d\\geq
3$\, the Fermi variety at every energy level is irreducible (modulo p
eriodicity). For $d=2$\, we prove that the Fermi variety at every ener
gy level except for the average of the potential is irreducible (modu
lo periodicity) and the Fermi variety at the average of the potential ha
s at most two irreducible components (modulo periodicity). \n\nThis is sh
arp since for $d=2$ and a constant potential $V$\, \n\nthe Fermi varie
ty at $V$-level has exactly two irreducible components (modulo periodic
ity). \n\nIn particular\, we show that the Bloch variety is irreducibl
e \n\n(modulo periodicity) for any $d\\geq 2$.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ilya Kachkovskiy (MSU)
DTSTART;VALUE=DATE-TIME:20210218T180000Z
DTEND;VALUE=DATE-TIME:20210218T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/7
DESCRIPTION:Title: Perturbative diagonalisation for Maryland-type quasiperiodic operators wi
th flat pieces\nby Ilya Kachkovskiy (MSU) as part of UCI Mathematical
Physics\n\n\nAbstract\nWe consider quasiperiodic operators on $\\Z^d$ with
unbounded monotone sampling functions ("Maryland-type")\, which are not r
equired to be strictly monotone and are allowed to have flat segments. Und
er several geometric conditions on the frequencies\, lengths of the segmen
ts\, and their positions\, we show that these operators enjoy Anderson loc
alization at large disorder.\n\nThe talk is based on the joint work with S
. Krymskii\, L. Parnovskii\, and R. Shterenberg.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Oluwadara Ogunkoya (University of Alabama at Birmingham)
DTSTART;VALUE=DATE-TIME:20210225T180000Z
DTEND;VALUE=DATE-TIME:20210225T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/8
DESCRIPTION:Title: Entanglement Entropy Bounds in the Higher Spin XXZ Chain\nby Oluwadar
a Ogunkoya (University of Alabama at Birmingham) as part of UCI Mathematic
al Physics\n\n\nAbstract\nWe consider the Heisenberg XXZ spin-$J$ chain ($
J\\in\\mathbb{N}/2$) with anisotropy parameter $\\Delta$. Assuming that $\
\Delta>2J$\, and introducing threshold energies $E_{K}:=K\\left(1-\\frac{2
J}{\\Delta}\\right)$\, we show that the bipartite entanglement entropy (EE
) of states belonging to any spectral subspace with energy less than $E_{K
+1}$ satisfy a logarithmically corrected area law with prefactor $(2\\lflo
or K/J\\rfloor-2)$.\n\nThis generalizes previous results by Beaud and Warz
el as well as Abdul-Rahman\, Stolz and one of the authors (C. Fischbacher)
\, who covered the spin-$1/2$ case.\n
LOCATION:
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christoph Fischbacher (University of Alabama at Birmingham)
DTSTART;VALUE=DATE-TIME:20210304T180000Z
DTEND;VALUE=DATE-TIME:20210304T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/9
DESCRIPTION:Title: Entanglement Entropy Bounds in the Higher Spin XXZ Chain\nby Christop
h Fischbacher (University of Alabama at Birmingham) as part of UCI Mathema
tical Physics\n\nInteractive livestream: https://uci.zoom.us/j/93076750122
?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\n\nAbstract
\nWe consider the Heisenberg XXZ spin-$J$ chain ($J\\in\\mathbb{N}/2$) wit
h anisotropy parameter $\\Delta$. Assuming that $\\Delta>2J$\, and introdu
cing threshold energies $E_{K}:=K\\left(1-\\frac{2J}{\\Delta}\\right)$\, w
e show that the bipartite entanglement entropy (EE) of states belonging to
any spectral subspace with energy less than $E_{K+1}$ satisfy a logarithm
ically corrected area law with prefactor $(2\\lfloor K/J\\rfloor-2)$.\n\nT
his generalizes previous results by Beaud and Warzel as well as Abdul-Rahm
an\, Stolz and C. Fischbacher\, who covered the spin-$1/2$ case.\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maximilian Pechmann (University of Tennessee\, Knoxville)
DTSTART;VALUE=DATE-TIME:20210311T180000Z
DTEND;VALUE=DATE-TIME:20210311T190000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/10
DESCRIPTION:Title: Bose-Einstein condensation in one-dimensional noninteracting Bose gases
in the presence of soft Poissonian obstacles\nby Maximilian Pechmann (
University of Tennessee\, Knoxville) as part of UCI Mathematical Physics\n
\nInteractive livestream: https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQT
BuNUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\n\nAbstract\nWe study Bose
--Einstein condensation (BEC) in one-dimensional noninteracting Bose gases
in Poisson random potentials on $\\mathbb R$ with single-site potentials
that are nonnegative\, compactly supported\, and bounded measurable functi
ons in the grand-canonical ensemble at positive temperatures and in the th
ermodynamic limit. For particle densities larger than a critical one\, we
prove the following: With arbitrarily high probability when choosing the f
ixed strength of the random potential sufficiently large\, BEC where only
the ground state is macroscopically occupied occurs. If the strength of th
e Poisson random potential converges to infinity in a certain sense but ar
bitrarily slowly\, then this kind of BEC occurs in probability and in the
$r$th mean\, $r \\ge 1$. Furthermore\, in Poisson random potentials of any
fixed strength an arbitrarily high probability for type-I g-BEC is also o
btained by allowing sufficiently many one-particle states to be macroscopi
cally occupied.\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Shiwen Zhang (University of Minnesota)
DTSTART;VALUE=DATE-TIME:20210415T170000Z
DTEND;VALUE=DATE-TIME:20210415T180000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/11
DESCRIPTION:by Shiwen Zhang (University of Minnesota) as part of UCI Mathe
matical Physics\n\nInteractive livestream: https://uci.zoom.us/j/930767501
22?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\nAbstract
: TBA\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rui Han (LSU)
DTSTART;VALUE=DATE-TIME:20210513T170000Z
DTEND;VALUE=DATE-TIME:20210513T180000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/12
DESCRIPTION:by Rui Han (LSU) as part of UCI Mathematical Physics\n\nIntera
ctive livestream: https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQU
xFMkQ2QnRFQT09\nPassword hint: Thouless\nAbstract: TBA\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Milivoje Lukic (Rice)
DTSTART;VALUE=DATE-TIME:20210422T170000Z
DTEND;VALUE=DATE-TIME:20210422T180000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/13
DESCRIPTION:by Milivoje Lukic (Rice) as part of UCI Mathematical Physics\n
\nInteractive livestream: https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQT
BuNUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\nAbstract: TBA\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Simon Larson (Caltech)
DTSTART;VALUE=DATE-TIME:20210506T170000Z
DTEND;VALUE=DATE-TIME:20210506T180000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/14
DESCRIPTION:by Simon Larson (Caltech) as part of UCI Mathematical Physics\
n\nInteractive livestream: https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQ
TBuNUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\nAbstract: TBA\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
BEGIN:VEVENT
SUMMARY:Zhenghe Zhang (UCR)
DTSTART;VALUE=DATE-TIME:20210429T170000Z
DTEND;VALUE=DATE-TIME:20210429T180000Z
DTSTAMP;VALUE=DATE-TIME:20210228T182726Z
UID:Thouless/15
DESCRIPTION:by Zhenghe Zhang (UCR) as part of UCI Mathematical Physics\n\n
Interactive livestream: https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBu
NUhxQUxFMkQ2QnRFQT09\nPassword hint: Thouless\nAbstract: TBA\n
LOCATION:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnR
FQT09
URL:https://uci.zoom.us/j/93076750122?pwd=Y3pLdndoQTBuNUhxQUxFMkQ2QnRFQT09
END:VEVENT
END:VCALENDAR