46 research outputs found
Quantum information erasure inside black holes
An effective field theory for infalling observers in the vicinity of a
quasi-static black hole is given in terms of a freely falling lattice
discretization. The lattice model successfully reproduces the thermal spectrum
of outgoing Hawking radiation, as was shown by Corley and Jacobson, but can
also be used to model observations made by a typical low-energy observer who
enters the black hole in free fall at a prescribed time. The explicit short
distance cutoff ensures that, from the viewpoint of the infalling observer, any
quantum information that entered the black hole more than a scrambling time
earlier has been erased by the black hole singularity. This property, combined
with the requirement that outside observers need at least of order the
scrambling time to extract quantum information from the black hole, ensures
that a typical infalling observer does not encounter drama upon crossing the
black hole horizon in a theory where black hole information is preserved for
asymptotic observers.Comment: 20 pages, 3 figures, some minor correction
Black hole holography and mean field evolution
Holographic theories representing black holes are expected to exhibit quantum
chaos. We argue if the laws of quantum mechanics are expected to hold for
observers inside such black holes, then such holographic theories must have a
mean field approximation valid for typical black hole states, and for
timescales approaching the scrambling time. Using simple spin models as
examples, we examine the predictions of such an approach for observers inside
black holes, and more speculatively inside cosmological horizons.Comment: 11 pages, 5 figure
Taking the Temperature of a Black Hole
We use the global embedding of a black hole spacetime into a higher
dimensional flat spacetime to define a local temperature for observers in free
fall outside a static black hole. The local free-fall temperature remains
finite at the event horizon and in asymptotically flat spacetime it approaches
the Hawking temperature at spatial infinity. Freely falling observers outside
an AdS black hole do not see any high-temperature thermal radiation even if the
Hawking temperature of such black holes can be arbitrarily high.Comment: latex, 14 pages, 4 figures, v3: added references, matches published
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Lifshitz hydrodynamics at generic from a moving black brane
A Lifshitz black brane at generic dynamical critical exponent , with
non-zero linear momentum along the boundary, provides a holographic dual
description of a non-equilibrium steady state in a quantum critical fluid, with
Lifshitz scale invariance but without boost symmetry. We consider moving
Lifshitz branes in Einstein-Maxwell-Dilaton gravity and obtain the
non-relativistic stress tensor complex of the dual field theory via a suitable
holographic renormalisation procedure. The resulting black brane hydrodynamics
and thermodynamics are a concrete holographic realization of a Lifshitz perfect
fluid with a generic dynamical critical exponent.Comment: 18 page
Probing emergent geometry through phase transitions in free vector and matrix models
Boundary correlation functions provide insight into the emergence of an
effective geometry in higher spin gravity duals of O(N) or U(N) symmetric field
theories. On a compact manifold, the singlet constraint leads to nontrivial
dynamics at finite temperature and large N phase transitions even at vanishing
't Hooft coupling. At low temperature, the leading behavior of boundary
two-point functions is consistent with propagation through a bulk thermal anti
de Sitter space. Above the phase transition, the two-point function shows
significant departure from thermal AdS space and the emergence of localized
black hole like objects in the bulk. In adjoint models, these objects appear at
length scales of order of the AdS radius, consistent with a Hawking-Page
transition, but in vector models they are parametrically larger than the AdS
scale. In low dimensions, we find another crossover at large distances beyond
which the correlation function again takes a thermal AdS form, albeit with a
temperature dependent normalization factor.Comment: 24 pages, 1 table, 3 figure