http://arxiv.org/abs/1506.01353
Hawking Radiation Energy and Entropy from a Bianchi-Smerlak Semiclassical Black Hole
Shohreh Abdolrahimi,
Don N. Page
(Submitted on 2 Jun 2015)
Eugenio Bianchi and Matteo Smerlak have found a relationship between the Hawking radiation energy and von Neumann entropy in a conformal field emitted by a semiclassical two-dimensional black hole. We compare this relationship with what might be expected for unitary evolution of a quantum black hole in four and higher dimensions. If one neglects the expected increase in the radiation entropy over the decrease in the black hole Bekenstein-Hawking A/4 entropy that arises from the scattering of the radiation by the barrier near the black hole, the relation works very well, except near the peak of the radiation von Neumann entropy and near the final evaporation. These discrepancies are calculated and discussed as tiny differences between a semiclassical treatment and a quantum gravity treatment.
http://arxiv.org/abs/1506.01353
cMERA as Surface/State Correspondence in AdS/CFT
Masamichi Miyaji,
Tokiro Numasawa,
Noburo Shiba,
Tadashi Takayanagi,
Kento Watanabe
(Submitted on 3 Jun 2015)
We present how the surface/state correspondence, conjectured in
arXiv:1503.03542, works in the setup of AdS3/CFT2 by generalizing the formulation of cMERA. The boundary states in conformal field theories play a crucial role in our formulation and the bulk diffeomorphism is naturally taken into account. We give an identification of bulk local operators which reproduces correct scalar field solutions on AdS3. We also calculate the information metric for a locally excited state and show that it is given by that of 2d hyperbolic manifold, which is argued to describe the time slice of AdS3.
http://arxiv.org/abs/1506.01366
The BFSS model on the lattice
Veselin G. Filev,
Denjoe O'Connor
(Submitted on 3 Jun 2015)
We study the maximally supersymmetric BFFS model at finite temperature and its bosonic relative. For the bosonic model in p+1 dimensions, we find that it effectively reduces to a system of gauged Gaussian matrix models. The effective model captures the low temperature regime of the model including the phase transition. The mass becomes p1/3λ1/3 for large p, with λ the 'tHooft coupling. For p=9 simulations of the model give m=(1.90±.01)λ1/3, which is also the mass gap of the Hamiltonian. We argue that there is no `sign' problem in the maximally supersymmetric BFSS model and perform detailed simulations of several observables finding excellent agreement with AdS/CFT predictions when 1/α′ corrections are included.
http://arxiv.org/abs/1506.01337
Violations of the Born rule in cool state-dependent horizons
Donald Marolf,
Joseph Polchinski
(Submitted on 3 Jun 2015)
The black hole information problem has motivated many proposals for new physics. One idea, known as state-dependence, is that quantum mechanics must be generalized to describe the physics of black holes, and that fixed linear operators do not provide the fundamental description of experiences for infalling observers. Instead, such experiences are to be described by operators with an extra dependence on the global quantum state. We show that any implementation of this idea strong enough to remove firewalls from generic states requires massive violations of the Born rule. We also demonstrate a sense in which such violations are visible to infalling observers involved in preparing the initial state of the black hole. We emphasize the generality of our results; no details of any specific proposal for state-dependence are required.