|Speaker:||Sumit Das (Kentucky University)|
|Title:||DILATON COSMOLOGIES AND THEIR GAUGE THEORY DUALS|
|Date:||Tue, Jan 12, 2010, 13:15 - 14:45|
|Place:||Seminar Room at IPMU Prefab. B|
We discuss deformations of AdS_5 X S5 obtained by taking the boundary value of the dilaton to be time dependent. This background is dual to N=4 Yang-Mills with a time dependent 't Hooft coupling. The coupling
asymptotes to a large constant value in the far past and far future and attains a small value at an intermediate time. At this time, the bulk curvature becomes large and supergravity breaks down - this appears like
a space-like singularity. We use the dual gauge theory to ask if a meaningful time evolution exists beyond this time and show how a coherent state adiabatic approximation can be used to address this issue when the coupling is slowly varying. We argue that the final state should have a dual description which is mostly smooth AdS_5 X S5, but with possible presence of small black holes.