Found 5 result(s)
Triangular Seminar Iosif Bena (IPHT)
at: 15:00 room S1.04  abstract: Black holes appear to lead to information loss, thus violating one of the fundamental tenets of Quantum Mechanics. Recent InformationTheorybased arguments imply that information loss can only be avoided if at the scale of the black hole horizon there exists a structure (commonly called fuzzball or firewall) that allows information to escape. I will discuss the highlyunusual properties that this structure must have and how these properties emerge in the realization of this structure in String Theory via branes, fluxes and topology. I will then describe the implication of this structure for AdS_2 holography. 
Regular Seminar Iosif Bena (Saclay)
at: 14:00 room G.O. Jones 610  abstract: Antibranes in backgrounds that have charge dissolved in fluxes are a key ingredient in constructing a landscape (Multiverse) of deSitter vacua in String Theory, and also of constructing microstate solutions corresponding to nonsupersymmetric nearextremal black holes. There are several regimes of parameters in which one can study the physics of these antibranes, and I will show that in the regime of parameters where their gravitational backreaction is important, antibranes have a naked singularity that cannot be resolved either by brane polarization or by cloaking with a black hole horizon, and that signals a tachyonic instability. I will also present recent evidence that the theory on the wordvolume of antiD3 branes is finite to all loops. I will conclude by discussing the implications of these results for the Multiverse paradigm and for the Fuzzball proposal. 
Triangular Seminar Iosif Bena (Paris)
at: 15:00 room Blackett lecture room 3  abstract: I will review the construction of BPS and nonBPS multicenter black hole solutions, and describe a class of smooth solutions that have the same charges and asymptotics as black holes, but do not have a horizon. I will then discuss some of the properties of these solutions and argue that they should correspond to typical microstates of extremal black holes. If so, string theory would imply that a classical extremal black hole solution is a thermodynamic approximation of an ensemble of horizonless configurations, and that this solution stops giving a valid description of the physics at the scale of the horizon. I will finish by discussing the extension of this to nonextremal black holes and its implications for the information paradox. 
Regular Seminar Iosif Bena (Saclay)
at: 14:00 room 410 B  abstract:

Triangular Seminar Iosif Bena (SPhT Saclay)
at: 15:00 room Lecture Theatre 1, Blackett Lab  abstract:
