Wed, 30 May 2007
12:00
12:00
L3
Mon, 04 Jun 2007
12:00
12:00
L3
Evaluating gauge-theoretic amplitudes with twistor diagrams
Andrew Hodges
(Oxford)
Abstract
Amplitudes in gauge theory at tree-level can be expressed economically
in terms of twistor diagrams (hep-th/0503060, hep-th/0512336). This
formalism has recently been used to write down the 8-field scattering
amplitudes in a simple form, going beyond the results previously obtained
(hep-th/0603101). This talk will give an elementary account of how this is
done.
Wed, 06 Jun 2007
12:00
12:00
L3
Constructing Gauge Theory Amplitudes
Ruth Britto
(Amsterdam)
Abstract
Gauge theory amplitudes lie at the meeting ground of perturbative QCD and
twistor string theory. The past three years have seen dramatic
developments in the analytic computation of amplitudes and their
interpretation in twistor space geometry. I will discuss applications to
collider experiments and describe direct, systematic procedures for deriving
one-loop amplitudes from tree amplitudes, using new insights regarding
unitarity.
Mon, 28 May 2007
12:00
12:00
L3
Tue, 15 May 2007
14:15
14:15
L3
Polarized and half polarized U(1) symmetric vacuum spacetimes with AVTD behaviour
Yvonne Choquet Bruhat
(Universite Pierre and Marie Curie)
Mon, 14 May 2007
12:00
12:00
L3
Self-dual supergravity and twistor theory
Martin Wolf
(Imperial College, London)
Abstract
By generalizing and extending some of the earlier results derived by
Manin and by Merkulov, a twistor description is given of four-dimensional
N-extended (gauged) self-dual supergravity with and without cosmological
constant. In particular, superconformal structures are introduced and used
as a starting point to define complex quaternionic, quaternionic Kaehler and
hyper-Kaehler supermanifolds. A supersymmetry generalization of the Penrose
and Ward constructions are presented.