BEGIN:VCALENDAR
VERSION:2.0
PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Ben Davison (Edinburgh)
DTSTART:20201026T141500Z
DTEND:20201026T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/1
DESCRIPTION:Title: Coproducts in the cohomological DT theory of 3-Calabi-Yau completion
s\nby Ben Davison (Edinburgh) as part of Oxford Geometry and Analysis
Seminar\n\n\nAbstract\nGiven a suitably friendly category D we can take th
e 3-Calabi Yau completion of D and obtain a 3-Calabi-Yau category E. The a
rchetypal example has D as the category of coherent sheaves on a smooth qu
asiprojective surface\, then E is the category of coherent sheaves on the
total space of the canonical bundle - a quasiprojective 3CY variety. The m
oduli stack of semistable objects in the 3CY completion E supports a vanis
hing cycle-type sheaf\, the hypercohomology of which is the basic object i
n the study of the DT theory of E. Something extra happens when our input
category is itself 2CY: examples include the category of local systems on
a Riemann surface\, the category of coherent sheaves on a K3/Abelian surfa
ce\, the category of Higgs bundles on a smooth complete curve\, or the cat
egory of representations of a preprojective algebra. In these cases\, the
DT cohomology of E carries a cocommutative coproduct. I'll also explain ho
w this interacts with older algebraic structures in cohomological DT theor
y to provide a geometric construction of both well-known and new quantum g
roups.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Egor Shelukhin (Université de Montréal)
DTSTART:20201102T141500Z
DTEND:20201102T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/2
DESCRIPTION:Title: Smith theory in filtered Floer homology and Hamiltonian diffeomorphi
sms\nby Egor Shelukhin (Université de Montréal) as part of Oxford Ge
ometry and Analysis Seminar\n\n\nAbstract\nWe describe how Smith theory ap
plies in the setting of Hamiltonian Floer homology filtered by the action
functional\, and provide applications to questions regarding Hamiltonian d
iffeomorphisms\, including the Hofer-Zehnder conjecture on the existence o
f infinitely many periodic points and a question of McDuff-Salamon on Hami
ltonian diffeomorphisms of finite order.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Davesh Maulik (MIT)
DTSTART:20201109T141500Z
DTEND:20201109T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/3
DESCRIPTION:Title: Cohomology of the moduli of Higgs bundles and the Hausel-Thaddeus co
njecture\nby Davesh Maulik (MIT) as part of Oxford Geometry and Analys
is Seminar\n\n\nAbstract\nIn this talk\, I will discuss some results on th
e structure of the cohomology of the moduli space of stable SL_n Higgs bun
dles on a curve. \nOne consequence is a new proof of the Hausel-Thaddeus
conjecture proven previously by Groechenig-Wyss-Ziegler via p-adic integra
tion.\nWe will also discuss connections to the P=W conjecture if time perm
its. Based on joint work with Junliang Shen.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrea Mondino (Oxford)
DTSTART:20201116T141500Z
DTEND:20201116T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/4
DESCRIPTION:Title: Optimal transport\, Ricci curvature lower bounds and group actions\nby Andrea Mondino (Oxford) as part of Oxford Geometry and Analysis Sem
inar\n\n\nAbstract\nIn the talk I will survey the fast growing field of me
tric measure spaces satisfying a lower bound on Ricci Curvature\, in a syn
thetic sense via optimal transport. Particular emphasis will be given to d
iscuss how such (possibly non-smooth) spaces naturally (and usefully) exte
nd the class of smooth Riemannian manifolds with Ricci curvature bounded b
elow.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Vidit Nanda (Oxford)
DTSTART:20201123T141500Z
DTEND:20201123T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/5
DESCRIPTION:Title: Complex links and algebraic multiplicities\nby Vidit Nanda (Oxfo
rd) as part of Oxford Geometry and Analysis Seminar\n\n\nAbstract\nGiven a
nested pair X and Y of complex projective varieties\, there is a single p
ositive integer e which measures the singularity type of X inside Y. This
is called the Hilbert-Samuel multiplicity of Y along X\, and it appears in
the formulations of several standard intersection-theoretic constructions
including Segre classes\, Euler obstructions\, and various other multipli
cities. The standard method for computing e requires knowledge of the equa
tions which define X and Y\, followed by a (super-exponential) Grobner bas
is computation. In this talk we will connect the HS multiplicity to comple
x links\, which are fundamental invariants of (complex analytic) Whitney s
tratified spaces. Thanks to this connection\, the enormous computational b
urden of extracting e from polynomial equations reduces to a simple exerci
se in clustering point clouds. In fact\, one doesn't even need the polynom
ials which define X and Y: it suffices to work with dense point samples. T
his is joint work with Martin Helmer.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Soheyla Feyzbakhsh (Imperial)
DTSTART:20201130T141500Z
DTEND:20201130T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/6
DESCRIPTION:Title: Application of a Bogomolov-Gieseker type inequality to counting inva
riants\nby Soheyla Feyzbakhsh (Imperial) as part of Oxford Geometry an
d Analysis Seminar\n\n\nAbstract\nIn this talk\, I will work on a smooth p
rojective threefold X which satisfies the Bogomolov-Gieseker conjecture of
Bayer-Macrì-Toda\, such as the projective space P^3 or the quintic three
fold. I will show certain moduli spaces of 2-dimensional torsion sheaves o
n X are smooth bundles over Hilbert schemes of ideal sheaves of curves and
points in X. When X is Calabi-Yau this gives a simple wall crossing formu
la expressing curve counts (and so ultimately Gromov-Witten invariants) in
terms of counts of D4-D2-D0 branes. This is joint work with Richard Thoma
s.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dougal Davis (Edinburgh)
DTSTART:20201207T110000Z
DTEND:20201207T120000Z
DTSTAMP:20260404T131152Z
UID:OxGeom/7
DESCRIPTION:Title: Two perspectives on the stack of principal bundles on an elliptic cu
rve and its slices\nby Dougal Davis (Edinburgh) as part of Oxford Geom
etry and Analysis Seminar\n\n\nAbstract\nLet G be a reductive group\, E an
elliptic curve\, and Bun_G the moduli stack of principal G-bundles on E.
In this talk\, I will attempt to explain why Bun_G is a very interesting o
bject from the perspectives of both singularity theory on the one hand\, a
nd shifted symplectic geometry and representation theory on the other. In
the first part of the talk\, I will explain how to construct slices of Bun
_G through points corresponding to unstable bundles\, and how these are li
nked to certain singular algebraic surfaces and their deformations in the
case of a "subregular" bundle. In the second (probably much shorter) part\
, I will discuss the shifted symplectic geometry of Bun_G and its slices.
If time permits\, I will sketch how (conjectural) quantisations of these s
tructures should be related to some well known algebras of an "elliptic" f
lavour\, such as Sklyanin and Feigin-Odesskii algebras\, and elliptic quan
tum groups.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Ikenmeyer (University of Liverpool)
DTSTART:20210118T141500Z
DTEND:20210118T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/8
DESCRIPTION:Title: Representation theory in geometric complexity theory\nby Christi
an Ikenmeyer (University of Liverpool) as part of Oxford Geometry and Anal
ysis Seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Guillem Cazassus (University of Oxford)
DTSTART:20210125T141500Z
DTEND:20210125T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/9
DESCRIPTION:Title: Equivariant Lagrangian Floer homology and Extended Field theory\
nby Guillem Cazassus (University of Oxford) as part of Oxford Geometry and
Analysis Seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Krzysztof Ciosmak (University of Oxford)
DTSTART:20210201T141500Z
DTEND:20210201T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/10
DESCRIPTION:Title: Leaf decompositions in Euclidean spaces\nby Krzysztof Ciosmak (
University of Oxford) as part of Oxford Geometry and Analysis Seminar\n\n\
nAbstract\nIn the talk I shall discuss an approach to the localisation tec
hnique\, for spaces satisfying the curvature-dimension condition\, by mean
s of L1-optimal transport. Moreover\, I shall present recent work on a gen
eralisation of the technique to multiple constraints setting. Applications
of the theory lie in functional and geometric inequalities\, e.g. in the
Lévy-Gromov isoperimetric inequality.\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dan Abramovich (Brown University)
DTSTART:20210208T141500Z
DTEND:20210208T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/11
DESCRIPTION:Title: Punctured invariants and gluing\nby Dan Abramovich (Brown Unive
rsity) as part of Oxford Geometry and Analysis Seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Eckhard Meinrenken (University of Toronto)
DTSTART:20210215T141500Z
DTEND:20210215T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/12
DESCRIPTION:Title: Weightings and normal forms\nby Eckhard Meinrenken (University
of Toronto) as part of Oxford Geometry and Analysis Seminar\n\nAbstract: T
BA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Christian Bär (University of Potsdam)
DTSTART:20210222T141500Z
DTEND:20210222T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/13
DESCRIPTION:Title: Spaces of metrics of positive scalar curvature on manifolds with bo
undary\nby Christian Bär (University of Potsdam) as part of Oxford Ge
ometry and Analysis Seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Catherine Cannizzo (Stony Brook University)
DTSTART:20210301T141500Z
DTEND:20210301T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/14
DESCRIPTION:Title: Homological mirror symmetry for genus two curves\nby Catherine
Cannizzo (Stony Brook University) as part of Oxford Geometry and Analysis
Seminar\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Diane MacLagan (University of Warwick)
DTSTART:20210308T141500Z
DTEND:20210308T151500Z
DTSTAMP:20260404T131152Z
UID:OxGeom/15
DESCRIPTION:Title: The spine of the T-graph of the Hilbert scheme\nby Diane MacLag
an (University of Warwick) as part of Oxford Geometry and Analysis Seminar
\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OxGeom/15/
END:VEVENT
END:VCALENDAR