Geometry and Topology in Physical Models


International PhD Programme in Mathematics, Mathematical Physics and Computer Science


1. Global dynamics of asymptotically anti-de Sitter spacetimes

Polish supervisor: Piotr Bizoń
Cooperating partners: Lars Andersson (A. Einstein Institute, Potsdam)
Piotr T. Chru¶ciel (University of Vienna) Gary Gibbons (University of Cambridge)


Asymptotically anti-de Sitter (AdS) spacetimes have come to play a central role in theoretical physics, prominently due to the AdS/CFT correspondence which postulates a duality between supergravity on AdS x M (with M a compact manifold) and a conformal field theory (CFT) defined on the boundary I of the AdS bulk. One of the main open mathematical issues in this context is the problem of nonlinear stability of the exact AdS spacetime (the maximally symmetric solution of vacuum Einstein's equations with a negative cosmological constant Λ<0). Let us recall that the corresponding stability problems have been solved for Λ=0 (the famous proof of nonlinear stability of Minkowski spacetime by Christodoulou and Klainerman) and for Λ>0 (proofs of nonlinear stability of de Sitter spacetime by Friedrich and Anderson). The key hard feature of AdS (distinguishing it from the cases with nonnegative Λ) is the presence of the timelike boundary at spatial infinity, which gives the problem of stability a flavour of a Hamiltonian conservative system on a bounded domain and precludes asymptotic stability.

The goal of this project is to study different aspects of long-time dynamics of solutions of Einstein's equations with Λ<0 (both in vacuum and with matter fields) under certain simplifying symmetry assumptions (like spherical symmetry or cohomogeneity-two Bianchi IX triaxial symmetry). Of course, the student is not expected to solve the problem of nonlinear stability of AdS but we hope that his/her studies will shed light on the problem, in particular will generate a well-substantiated conjecture. More concretely, the student is expected to work on: i) the role of different boundary conditions for the fields at I in the Cauchy evolution, ii) the development of a numerical code for solving the full system of Einstein-matter equations (under 1+1 symmetry reduction) with Λ<0 in various dimensions, iii) the long-time evolution of small perturbations of AdS, in particular analyze a possibility of focusing of energy on small spatiotemporal scales, iv) formation of black holes and their asymptotic stability (due to, so called, quasinormal ringing) for large perturbations of AdS.