6 research outputs found
Black Hole Complementarity vs. Locality
The evaporation of a large mass black hole can be described throughout most
of its lifetime by a low-energy effective theory defined on a suitably chosen
set of smooth spacelike hypersurfaces. The conventional argument for
information loss rests on the assumption that the effective theory is a local
quantum field theory. We present evidence that this assumption fails in the
context of string theory. The commutator of operators in light-front string
theory, corresponding to certain low-energy observers on opposite sides of the
event horizon, remains large even when these observers are spacelike separated
by a macroscopic distance. This suggests that degrees of freedom inside a black
hole should not be viewed as independent from those outside the event horizon.
These nonlocal effects are only significant under extreme kinematic
circumstances, such as in the high-redshift geometry of a black hole.
Commutators of space-like separated operators corresponding to ordinary
low-energy observers in Minkowski space are strongly suppressed in string
theory.Comment: 32 pages, harvmac, 3 figure
Conformal Tightness of Holographic Scaling in Black Hole Thermodynamics
The near-horizon conformal symmetry of nonextremal black holes is shown to be
a mandatory ingredient for the holographic scaling of the scalar-field
contribution to the black hole entropy. This conformal tightness is revealed by
semiclassical first-principle scaling arguments through an analysis of the
multiplicative factors in the entropy due to the radial and angular degrees of
freedom associated with a scalar field. Specifically, the conformal SO(2,1)
invariance of the radial degree of freedom conspires with the area
proportionality of the angular momentum sums to yield a robust holographic
outcome.Comment: 23 pages, 1 figure. v2 & v3: expanded explanations and proofs,
references added, typos corrected; v3: published versio
The Stretched Horizon and Black Hole Complementarity
Three postulates asserting the validity of conventional quantum theory,
semi-classical general relativity and the statistical basis for thermodynamics
are introduced as a foundation for the study of black hole evolution. We
explain how these postulates may be implemented in a ``stretched horizon'' or
membrane description of the black hole, appropriate to a distant observer. The
technical analysis is illustrated in the simplified context of 1+1 dimensional
dilaton gravity. Our postulates imply that the dissipative properties of the
stretched horizon arise from a course graining of microphysical degrees of
freedom that the horizon must possess. A principle of black hole
complementarity is advocated. The overall viewpoint is similar to that
pioneered by 't~Hooft but the detailed implementation is different.Comment: (some misprints in equations have been fixed), 48 pages (including
figures), SU-ITP-93-1