Mon, 09 May 2016

12:00 - 13:00
L3

Mirror symmetry, supersymmetry and generalized geometry on SU(4)-structure vacua

Daniel Prins
(CEA/Saclay)
Abstract
Recently, there has been some progress in examining mirror symmetry beyond Calabi-Yau threefolds. I will discuss how this is related to flux vacua of type II supergravity on eight-dimensional manifolds equipped with SU(4)-structure. It will be shown that the natural framework to describe such vacua is generalized complex geometry. Two classes of type IIB solutions will be given, one of which is complex, the other symplectic, and I will describe in what sense these are mirror to one another.  
 
Tue, 10 May 2016

15:30 - 17:00
L4

Cohomological DT theory beyond the integrality conjecture

Ben Davison
(EPFL)
Abstract
The integrality conjecture is one of the central conjectures of the DT theory of quivers with potential, which itself is a key tool in understanding the local calculation of DT invariants on moduli spaces of coherent sheaves, as well as having deep links to geometric representation theory, noncommutative geometry and algebraic combinatorics.  I will explain some of the ingredients of the proof of this conjecture by myself and Sven Meinhardt.  In fact the proof gives much more than the original conjecture, which ultimately concerns identities in a Grothendieck ring of mixed Hodge structures associated to moduli spaces of representations, and proves that these equalities categorify to isomorphisms in the category of mixed Hodge structures.  I'll explain what this all means, as well as giving some applications of the categorified version of the theory.
Wed, 04 May 2016

16:00 - 17:00
C1

Classifying Groups up to Quasi-Isometry

Alex Margolis
Abstract

In his ICM address in 1983, Gromov proposed a program of classifying finitely generated groups up to quasi-isometry. One way of approaching this is by breaking a group down into simpler parts by means of a JSJ decomposition. I will give a survey of various JSJ theories and related quasi-isometric rigidity results, including recent work by Cashen and Martin.

Fri, 06 May 2016

11:00 - 12:00
C2

The cotangent complex I

Damian Rössler
((Oxford University))
Abstract

This is the first talk of the workshop organised by F. Brown, M. Kim and D. Rössler on Beilinson's approach to p-adic Hodge theory. 

In this talk, we shall give the definition and recall various properties of the cotangent complex, which was originally defined by L. Illusie in his monograph "Complexe cotangent et déformations" (Springer LNM 239, 1971).

Mon, 02 May 2016

12:00 - 13:00
L3

Another look at the information paradox: Soft black hole hair

Malcolm Perry
(Cambridge)
Abstract

The black hole information paradox comes about because of the classical no-hair theorems for black holes. I will discuss soft black hole hair in electrodynamics and in gravitation. Then some speculations on its relevance to the in formation paradox are presented.

Improved limits on dark matter annihilation in the Sun with the 79-string IceCube detector and implications for supersymmetry
Aartsen, M Abraham, K Ackermann, M Sarkar, S al., E Journal of Cosmology and Astroparticle Physics volume 2016 issue 04 022-022 (01 Apr 2016)
Mon, 20 Jun 2016
16:00
L1

Formal Moduli Problems

Jacob Lurie (Hardy Lecture Tour)
(Harvard University)
Abstract

Let X be a complex algebraic variety containing a point x. One of the central ideas of deformation theory is that the local structure of X near the point x can be encoded by a differential graded Lie algebra. In this talk, Jacob Lurie will explain this idea and discuss some generalizations to more exotic contexts.

Thu, 09 Jun 2016

16:00 - 17:00
C5

Cohomological Donaldson-Thomas Theory and quivers with potential

Aurelio Carlucci
(Oxford)
Abstract

Donaldson-Thomas theory was born as a mean to attach to Calabi-Yau 3-manifolds integers, invariant under small deformation of the complex structure. Subsequent evolutions have replaced integers with cohomological invariants, more flexible and with a broader range of applicable cases.

This talk is meant to be a gentle induction to the topic. We start with an introduction on virtual fundamental classes, and how they relate to deformation and obstruction spaces of a moduli space; then we pass on to the Calabi-Yau 3-dimensional case, stressing how some homological conditions are essential and can lead to generalisation. First we describe the global construction using virtual fundamental classes, then the local approach via the Behrend function and the virtual Euler characteristic.
We introduce quivers with potential, which provide a profitable framework in which to build DT-theory, as they are a source of moduli spaces locally presented as degeneracy loci. Finally, we overview the problem of categorification, introducing the DT-sheaf and showing how it relates to the numerical invariants.

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