Forthcoming events in this series
Mon, 15 Oct 2007
15:45
15:45
L3
Operads revisited
Ezra Getzler
(Nortwestern and Imperial)
Abstract
I will present a general formalism for understanding coloured operads of different flavours, such as cyclic operads, modular operads and topological field theories. The talk is based on arXiv:math/0701767.
Mon, 08 Oct 2007
15:45
15:45
L3
Quasiregular maps, hyperbolic groups, and rigidity of manifolds
Martin Bridson
(Oxford)
Abstract
Roughly speaking, a quasiregular map is a possibly-branched covering
map with bounded distortion. The theory of such maps was developed in
the 1970s to carry over to higher dimensions the more geometric aspects
of the theory of complex analytic functions of the plane. In this talk I
shall outline the proof of rigidity theorems describing the quasiregular
self-maps of hyperbolic manifolds.
These results rely on an extension of Sela's work concerning the
stability of self-maps of hyperbolic groups, and on
older topological ideas concerning discrete-open
and light-open maps, particularly their effect on fundamental groups.
I shall explain how these two sets of ideas also lead to topological
rigidity theorems.
This talk is based on a paper with a similar title by
Bridson, Hinkkanen and Martin (to appear in Compositio shortly).
http://www2.maths.ox.ac.uk/~bridson/papers/QRhyp/
Mon, 04 Jun 2007
15:45
15:45
L3
Mon, 14 May 2007
15:45
15:45
L3
Mon, 07 May 2007
15:45
15:45
L3
Local-to-global principles for classifying spaces
Jesper Grodal
(Copenhagen)
Abstract
In this talk I will show how one can sometimes "uncomplete" the p-completed
classifying space of a finite group, to obtain the original (non-completed)
classifying space, and hence the original finite group. This "uncompletion"
process is closely related to well-known local-to-global questions in group
theory, such as the classification of finite simple groups. The approach goes
via the theory of p-local finite groups. This talk is a report on joint work
with Bob Oliver.
Mon, 05 Mar 2007
15:45
15:45
L3
Mon, 05 Mar 2007
14:15
14:15
L3
K-THEORY DAY : Trees, building, elliptic operators, and K-theory for group C*-algebras
Paul Baum
(Penn State)
Mon, 19 Feb 2007
15:45
15:45
L3
Mon, 05 Feb 2007
15:45
15:45
L3
Mon, 29 Jan 2007
15:45
15:45
L3
Mon, 22 Jan 2007
15:45
15:45
L3
Mon, 15 Jan 2007
15:45
15:45
L3
Description of invariant complex structures and calculation of related Chern numbers on generalized symmetric spaces
Svjetlana Terzic
Mon, 08 Jan 2007
15:45
15:45
L3
An algebraic model for the loops on the p-completion of the classifying space of a finite group
Dave Benson
(Aberdeen)
Mon, 20 Nov 2006
15:45
15:45
L3
Characteristic classes of A-infinity algebras
Alastair Hamilton
(Bonn)
Abstract
There is a construction, due to Kontsevich, which produces cohomology classes in moduli spaces of Riemann surfaces from the initial data of an A-infinity algebra with an invariant inner product -- a kind of homotopy theoretic notion of a Frobenius algebra.
In this talk I will describe a version of this construction based on noncommutative symplectic geometry and use it to show that homotopy equivalent A-infinity algebras give rise to cohomologous classes. I will explain how the whole framework can be adapted to deal with Topological Conformal Field Theories in the sense of Costello, Kontsevich and Segal.
Mon, 13 Nov 2006
15:45
15:45
L3
Topology of moduli space III
Prof Ulrike Tillmann
(Oxford)
Abstract
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