112 research outputs found
Black hole singularity in AdS/CFT
We present a short review of hep-th/0306170. In the context of AdS/CFT
correspondence, we explore what information from behind the horizon of the bulk
black hole geometry can be found in boundary CFT correlators. In particular, we
argue that the CFT correlators contain distinct, albeit subtle, signals of the
black hole singularity.Comment: 7 pages, 2 figures, AMSLaTeX (ws-procs9x6.cls included). Presented at
QTS3 (Cincinnati, Ohio, Sept. 10-14, 2003
Note on Small Black Holes in AdS_p x S^q
It is commonly believed that small black holes in AdS_5 x S^5 can be
described by the ten dimensional Schwarzschild solution. This requires that the
self-dual five-form (which is nonzero in the background) does not fall through
the horizon and cause the black hole to grow. We verify that this is indeed the
case: There are static solutions to the five-form field equations in a ten
dimensional Schwarzschild spacetime. Similar results hold for other backgrounds
AdS_p x S^q of interest in supergravity.Comment: 11 pages, 1 figur
Topological string entanglement
We investigate how topological entanglement of Chern-Simons theory is
captured in a string theoretic realization. Our explorations are motivated by a
desire to understand how quantum entanglement of low energy open string degrees
of freedom is encoded in string theory (beyond the oft discussed classical
gravity limit). Concretely, we realize the Chern-Simons theory as the
worldvolume dynamics of topological D-branes in the topological A-model string
theory on a Calabi-Yau target. Via the open/closed topological string duality
one can map this theory onto a pure closed topological A-model string on a
different target space, one which is related to the original Calabi-Yau
geometry by a geometric/conifold transition. We demonstrate how to uplift the
replica construction of Chern-Simons theory directly onto the closed string and
show that it provides a meaningful definition of reduced density matrices in
topological string theory. Furthermore, we argue that the replica construction
commutes with the geometric transition, thereby providing an explicit closed
string dual for computing reduced states, and Renyi and von Neumann entropies
thereof. While most of our analysis is carried out for Chern-Simons on S^3, the
emergent picture is rather general. Specifically, we argue that quantum
entanglement on the open string side is mapped onto quantum entanglement on the
closed string side and briefly comment on the implications of our result for
physical holographic theories where entanglement has been argued to be crucial
ingredient for the emergence of classical geometry.Comment: 48 pages + appendices, many tikz fgures. v2: added clarification
Holographic entropy relations
We develop a framework for the derivation of new information theoretic
quantities which are natural from a holographic perspective. We demonstrate the
utility of our techniques by deriving the tripartite information (the quantity
associated to monogamy of mutual information) using a set of abstract arguments
involving bulk extremal surfaces. Our arguments rely on formal manipulations of
surfaces and not on local surgery or explicit computation of entropies through
the holographic entanglement entropy prescriptions. As an application, we show
how to derive a family of similar information quantities for an arbitrary
number of parties. The present work establishes the foundation of a broader
program that aims at the understanding of the entanglement structures of
geometric states for an arbitrary number of parties. We stress that our method
is completely democratic with respect to bulk geometries and is equally valid
in static and dynamical situations. While rooted in holography, we expect that
our construction will provide a useful characterization of multipartite
correlations in quantum field theories.Comment: v1: 58 pages, 1 pdf figur
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