10 research outputs found
Information Spreading in Interacting String Field Theory
The commutator of string fields is considered in the context of light cone
string field theory. It is shown that the commutator is in general
non--vanishing outside the string light cone. This could have profound
implications for our understanding of the localization of information in
quantum gravity.Comment: 10 pages, 1 figure, harvmac and epsf, UCSBTH-94-07, SU-ITP-94-
String Physics and Black Holes
In these lectures we review the quantum physics of large Schwarzschild black
holes. Hawking's information paradox, the theory of the stretched horizon and
the principle of black hole complementarity are covered. We then discuss how
the ideas of black hole complementarity may be realized in string theory.
Finally, arguments are given that the world may be a hologram. Lectures
delivered at ICTP Spring School on String Theory, Gauge Theory, and Quantum
Gravity, 1995.Comment: 20 pages, Latex (needs espcrc2.sty), 6 figure
Recommended from our members
Method and apparatus for electromagnetic powder deposition
The present invention provides a method for depositing powder particles on a substrate. The method comprises forming a planar plasma armature, accelerating the plasma armature, accelerating a column of gas with the plasma armature; and accelerating the powder particles with the column of gas. The present invention provides for a railgun, comprising first and second conducting rails, and first and second insulating rails. The insulating and conducting rails form a bore of the railgun. The first and second conducting rails are separated by the insulating rails. At least one of the rails has a port in the wall thereof, the port is adapted to introducing powder particles into the bore.Board of Regents, University of Texas Syste
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
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
Recommended from our members
Electromagnetic seismology vibrator systems and methods
An electromagnetic system having a reaction mass with a field winding embedded therein, a base plate having an inner annular surface and an outer annular surface, and an armature winding coupled to at least a portion of the inner annular surface and at least a portion of the outer annular surface of an upper end portion of the base plate. In operation, directing an electric current in at least one of the field winding and the armature winding causes at least one of the base plate and the reaction mass to move relative to each other. The electromagnetic system can be used for seismic exploration and vibroseis applications, among other uses.Board of Regents, University of Texas Syste