2,212,345 research outputs found
Teleportation Topology
We discuss the structure of teleportation. By associating matrices to the
preparation and measurement states, we show that for a unitary transformation M
there is a full teleportation procedure for obtaining M|S> from a given state
|S>. The key to this construction is a diagrammatic intepretation of matrix
multiplication that applies equally well to a topological composition of a
maximum and a minimum that underlies the structure of the teleportation. This
paper is a preliminary report on joint work with H. Carteret and S. Lomonaco.Comment: LaTeX document, 16 pages, 8 figures, Talk delivered at the Xth
International Conference on Quantum Optics, Minsk, Belaru
Zero area singularities in general relativity and inverse mean curvature flow
First we restate the definition of a Zero Area Singularity, recently
introduced by H. Bray. We then consider several definitions of mass for these
singularities. We use the Inverse Mean Curvature Flow to prove some new results
about the mass of a singularity, the ADM mass of the manifold, and the capacity
of the singularity.Comment: 13 page
Representations of SU(1,1) in Non-commutative Space Generated by the Heisenberg Algebra
SU(1,1) is considered as the automorphism group of the Heisenberg algebra H.
The basis in the Hilbert space K of functions on H on which the irreducible
representations of the group are realized is explicitly constructed. The
addition theorems are derived.Comment: Latex, 8 page
Casimir energy inside a triangle
For certain class of triangles (with angles proportional to \fr{\pi}{N},
) we formulate image method by making use of the group generated
by reflections with respect to the three lines which form the triangle under
consideration. We formulate the renormalization procedure by classification of
subgroups of and corresponding fixed points in the triangle. We also
calculate Casimir energy for such geometries, for scalar massless fields. More
detailed calculation is given for odd .Comment: Latex, 13 page
Gravitons and Lightcone Fluctuations II: Correlation Functions
A model of a fluctuating lightcone due to a bath of gravitons is further
investigated. The flight times of photons between a source and a detector may
be either longer or shorter than the light propagation time in the background
classical spacetime, and will form a Gaussian distribution centered around the
classical flight time. However, a pair of photons emitted in rapid succession
will tend to have correlated flight times. We derive and discuss a correlation
function which describes this effect. This enables us to understand more fully
the operational significance of a fluctuating lightcone. Our results may be
combined with observational data on pulsar timing to place some constraints on
the quantum state of cosmological gravitons.Comment: 16 pages and two figures, uses eps
Semiclassical Gravity Theory and Quantum Fluctuations
We discuss the limits of validity of the semiclassical theory of gravity in
which a classical metric is coupled to the expectation value of the stress
tensor. It is argued that this theory is a good approximation only when the
fluctuations in the stress tensor are small. We calculate a dimensionless
measure of these fluctuations for a scalar field on a flat background in
particular cases, including squeezed states and the Casimir vacuum state. It is
found that the fluctuations are small for states which are close to a coherent
state, which describes classical behavior, but tend to be large otherwise. We
find in all cases studied that the energy density fluctuations are large
whenever the local energy density is negative. This is taken to mean that the
gravitational field of a system with negative energy density, such as the
Casimir vacuum, is not described by a fixed classical metric but is undergoing
large metric fluctuations. We propose an operational scheme by which one can
describe a fluctuating gravitational field in terms of the statistical behavior
of test particles. For this purpose we obtain an equation of the form of the
Langevin equation used to describe Brownian motion.Comment: In REVTEX. 20pp + 4 figures(not included, available upon request)
TUTP-93-
Gauge Structure of Vacuum String Field Theory
We study the gauge structure of vacuum string field theory expanded around
the D-brane solution, namely, the gauge transformation and the transversality
condition of the massless vector fluctuation mode. We find that the gauge
transformation on massless vector field is induced as an anomaly; an infinity
multiplied by an infinitesimal factor. The infinity comes from the singularity
at the edge of the eigenvalue distribution of the Neumann matrix, while the
infinitesimal factor from the violation of the equation of motion of the
fluctuation modes due to the regularization for the infinity. However, the
transversality condition cannot be obtained even if we take into account the
anomaly contribution.Comment: 19 pages, LaTeX2
- …