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BEGIN:VEVENT
SUMMARY:Eckhard Meinrenken (Toronto)
DTSTART;VALUE=DATE-TIME:20200416T151500Z
DTEND;VALUE=DATE-TIME:20200416T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/1
DESCRIPTION:Title: Van Est differentiation and Van Est integration\nby Eck
hard Meinrenken (Toronto) as part of Global Poisson webinar\n\nLecture hel
d in Zoom.\n\nAbstract\nThe classical Van Est theory relates the smooth co
homology of Lie groups with the cohomology of the associated Lie algebra.
Some aspects of this theory generalize to Lie groupoids and their Lie alge
broids. In this talk\, we revisit the van Est theory using the Perturbatio
n Lemma from homological algebra. This leads to precise descriptions of th
e van Est differentiation and integration at the level of cochains. The ta
lk is based on recent work with Maria Amelia Salazar.\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Rui Loja Fernandes (Urbana-Champaign)
DTSTART;VALUE=DATE-TIME:20200409T151500Z
DTEND;VALUE=DATE-TIME:20200409T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/2
DESCRIPTION:Title: Local models around Poisson submanifolds\nby Rui Loja F
ernandes (Urbana-Champaign) as part of Global Poisson webinar\n\nAbstract:
TBA\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pavel Etingof (MIT)
DTSTART;VALUE=DATE-TIME:20200423T151500Z
DTEND;VALUE=DATE-TIME:20200423T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/3
DESCRIPTION:Title: Short star-products for filtered quantizations\nby Pave
l Etingof (MIT) as part of Global Poisson webinar\n\nLecture held in Zoom.
\n\nAbstract\nLet $A$ be a filtered Poisson algebra with Poisson bracket $
\\lbrace{\,\\rbrace}$ of degree $-2$. A {\\it star product} on $A$ is an a
ssociative product $*: A\\otimes A\\to A$ given by $$a*b=ab+\\sum_{i\\ge 1
}C_i(a\,b)\,$$ where $C_i$ has degree $-2i$ and $C_1(a\,b)-C_1(b\,a)=\\lbr
ace{a\,b\\rbrace}$. We call the product * {\\it even} if $C_i(a\,b)=(-1)
^iC_i(b\,a)$ for all $i$\, and call it {\\it short} if $C_i(a\,b)=0$ whene
ver $i>{\\rm min}({\\rm deg}(a)\, {\\rm deg}(b))$.\n\nMotivated by three-d
imensional $N=4$ superconformal field theory\, In 2016 Beem\, Peelaers and
Rastelli considered short even star-products for homogeneous symplectic s
ingularities (more precisely\, hyperK\\"ahler cones) and conjectured that
that they exist and depend on finitely many parameters. We prove the depen
dence on finitely many parameters in general and existence for a large cla
ss of examples\, using the connection of this problem with zeroth Hochschi
ld homology of quantizations suggested by Kontsevich.\n\nBeem\, Peelaers a
nd Rastelli also computed the first few terms of short quantizations for K
leinian singularities of type A\, which were later computed to all orders
by Dedushenko\, Pufu and Yacoby. We will discuss some generalizations of t
hese results.\n\nThis is joint work with Douglas Stryker.\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alan Weinstein (UC Berkeley and Stanford)
DTSTART;VALUE=DATE-TIME:20200430T151500Z
DTEND;VALUE=DATE-TIME:20200430T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/4
DESCRIPTION:Title: Failure of Twisted Poisson Property for Monopole Plasma
\nby Alan Weinstein (UC Berkeley and Stanford) as part of Global Poisson w
ebinar\n\nLecture held in Zoom.\n\nAbstract\nAlthough the dynamical system
for a charged particle in a continuous background distribution of magneti
c monopoles is given by a twisted Poisson structure\, that for a plasm
a of such particles is not. (Joint work with Manuel Lainz and Cristina Sar
dón)\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Brent Pym (McGill)
DTSTART;VALUE=DATE-TIME:20200507T151500Z
DTEND;VALUE=DATE-TIME:20200507T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/5
DESCRIPTION:Title: Holonomic Poisson manifolds\nby Brent Pym (McGill) as p
art of Global Poisson webinar\n\nLecture held in Zoom.\n\nAbstract\nHolono
micity is a new sort of nondegeneracy condition for\nholomorphic Poisson s
tructures\, closely related to the notion of a log\nsymplectic form\, and
intimately connected with the geometry of\nWeinstein's modular vector fiel
d. It encompasses many natural Poisson\nstructures arising in gauge theo
ry\, representation theory\, and algebraic\ngeometry. The motivation for
the definition comes from deformation\ntheory: a Poisson manifold is holo
nomic when its space of deformations\nis "as finite-dimensional as possibl
e"\, in a sense I will make precise\nduring the talk (via D-modules). I
will describe the basic theory and\nexamples of holonomic Poisson manifold
s\, along with some concrete\nclassification results\, including the disco
very of many new irreducible\ncomponents of the moduli space of Poisson fo
urfolds. This talk is based\non joint works with Schedler\, and Matviich
uk--Schedler.\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eva Miranda (UPC)
DTSTART;VALUE=DATE-TIME:20200514T151500Z
DTEND;VALUE=DATE-TIME:20200514T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/6
DESCRIPTION:Title: From b-Poisson manifolds to singular contact structures
\nby Eva Miranda (UPC) as part of Global Poisson webinar\n\nLecture held i
n Zoom.\n\nAbstract\nTaking as starting point motivating examples from cel
estial mechanics and fluid dynamics\, we introduce the odd-dimensional cou
nterpart of b-Poisson/log-symplectic structures as Jacobi structures with
transversality conditions.\nWe discuss the basic theory and some construct
ions. In particular\, we prove that a connected component of a convex
hypersurface of a contact manifold can be realized as a connected componen
t of the critical set of a $b^m$-contact structure. In dimension 3\, this
construction yields the existence of a generic set of surfaces $Z$ such th
at the pair $(M\,Z)$ is a $b^{2k}$-contact manifold and $Z$ is its critica
l hypersurface.\n\n We also consider classical problems in Hamiltonian/R
eeb dynamics and address the Weinstein conjecture on the existence of peri
odic orbits of the Reeb vector field in this singular set-up. We end up th
is talk with some applications of this singular Weinstein conjecture to th
e motivating examples discussed at the beginning.\n\nThis is joint work wi
th Cédric Oms.\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Nicolai Reshetikhin (UC Berkeley)
DTSTART;VALUE=DATE-TIME:20200521T151500Z
DTEND;VALUE=DATE-TIME:20200521T171500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/7
DESCRIPTION:Title: Integrable systems of Calogero-Moser type and moduli sp
aces of flat connections\nby Nicolai Reshetikhin (UC Berkeley) as part of
Global Poisson webinar\n\nLecture held in Zoom.\n\nAbstract\nThe talk will
be focused on spin Calogero-Moser systems related to symmetric spaces. Th
ey have natural generalizations related to moduli spaces of flat connectio
ns.\n
LOCATION:Lecture held in Zoom
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tudor Ratiu (EPFL and Shanghai)
DTSTART;VALUE=DATE-TIME:20200528T151500Z
DTEND;VALUE=DATE-TIME:20200528T161500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/8
DESCRIPTION:Title: Differential character valued momentum maps and the Tei
chmüller space\nby Tudor Ratiu (EPFL and Shanghai) as part of Global Pois
son webinar\n\n\nAbstract\nIt is well-known that the actions of several di
ffeomorphism groups of geometric interest do not admit momentum maps. The
definition of the Teichmüller space via Riemannian geometry strongly sugg
est that it is a symplectic reduced space. I will present an extension of
the classical momentum map which always exists for actions of diffeomorphi
sm groups possessing the crucial Noether property. This extended momentum
map has no longer values in (pre)duals of Lie algebras\; its values are in
differential character groups. This extended momentum map encodes discret
e topological information\, something the classical momentum map cannot do
. In order to focus the presentation\, the Teichmüller space will serve a
s the example of this theory. The talk is based on joint work with Tobias
Diez from TU Delft.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maxim Kontsevich (IHÉS)
DTSTART;VALUE=DATE-TIME:20200604T151500Z
DTEND;VALUE=DATE-TIME:20200604T161500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/9
DESCRIPTION:Title: Quantum minimal surface and noncommutative Kaehler geom
etry\nby Maxim Kontsevich (IHÉS) as part of Global Poisson webinar\n\n\nA
bstract\nI will talk about several interrelated topics\, based on works 19
03.10792 and 2003.03171. Minimal surfaces in Euclidean space can be approx
imated (in sense of Berezin-Toeplitz quantization) by representations of Y
ang-Mills algebra given by relations $\\forall i\\\,\\sum_j[X_j\,[X_j\,X_i
]]=0$ where $X_i$ are self-adjoint operators. Similarly\, complex affine c
urves are approximated by representations of hermitian Yang-Mills algebra
$\\sum_k [Z_k^\\dagger\,Z_k]=\\hbar\\cdot id$ where $Z_i$ are commuting op
erators (but not self-adjoint in general). I will explain how the latter e
quation appears in the context of a version of Kaehler geometry for noncom
mutative algebras.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Boris Khesin (Toronto)
DTSTART;VALUE=DATE-TIME:20200611T151500Z
DTEND;VALUE=DATE-TIME:20200611T161500Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/10
DESCRIPTION:Title: Hamiltonian geometry of compressible fluids\nby Boris K
hesin (Toronto) as part of Global Poisson webinar\n\n\nAbstract\nWe descri
be a geometric framework to study Newton's equations on infinite-dimension
al configuration spaces of diffeomorphisms and smooth probability densitie
s. It turns out that several important PDEs of hydrodynamical origin can b
e described in this framework in a natural way. In particular\, the so-cal
led Madelung transform between the Schrödinger-type equations on wave fun
ctions and Newton's equations on densities turns out to be a Kähler map b
etween the corresponding phase spaces\, equipped with the Fubini-Study and
Fisher-Rao information metrics. This is a joint work with G.Misiolek and
K.Modin.\n
END:VEVENT
BEGIN:VEVENT
SUMMARY:Evgeny Sklyanin (York)
DTSTART;VALUE=DATE-TIME:20200528T080000Z
DTEND;VALUE=DATE-TIME:20200528T100000Z
DTSTAMP;VALUE=DATE-TIME:20200705T030754Z
UID:globalpoisson/12
DESCRIPTION:Title: Groupes de Lie et espaces des modules\nby Evgeny Sklyan
in (York) as part of Global Poisson webinar\n\nAbstract: TBA\n
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