Brane world gravity

Elizabeth Winstanley, University of Sheffield E.Winstanley@sheffield.ac.uk

A half-day meeting entitled ``Brane-world gravity" was held at Imperial College London on 13th November 2002, under the auspices of the Gravitational Physics Group of the Institute of Physics. The meeting gave an overview of the state of the art in brane world gravity, in a form accessible to non-experts and the many graduate students present.

John March-Russell began with an overview of the physics of brane worlds, including the latest experimental constraints, from colliders, astrophysics and cosmology. He concentrated on the phenomenology of the simplest brane-world model, of Arkani-Hamed, Dimopoulos and Dvali, in which the large extra dimensions are flat but compactified. Ruth Gregory then discussed gravity on the brane, including the construction of brane-world cosmology geometries using patches of Schwarzschild-anti-de Sitter space. She also addressed the more difficult (and as yet unsolved) problem of finding a metric which describes a black hole on the brane. Neil Turok's talk on the cosmology of brane worlds prompted much lively debate. He reviewed recent work with Tolley and Steinhardt on the cyclic universes resulting from colliding branes.

After a break for tea and discussion, Christian Trenkel described the latest experimental work in Birmingham and elsewhere to test gravity at short distances, in particular looking for the deviations from Newtonian gravity predicted by brane-world models. Marco Cavaglia talked about the possibilities of black hole production at the next generation of colliders, including the production cross-sections and decay signatures. Finally, Toby Wiseman described new pure gravity solutions of low-energy string theory representing higher-dimensional black holes, uniform homogeneous strings and non-uniform black strings.

Many thanks to David Wands for organizing a very successful meeting.