4,740 research outputs found
Slavnov-Taylor identity for nonequilibrium quark-gluon plasma
Within the closed-time-path formalism of nonequilibrium QCD, we derive a
Slavnov-Taylor (ST) identity for the gluon polarization tensor. The ST identity
takes the same form both in Coulomb and covariant gauges. Application to
quasi-uniform quark-gluon plasma (QGP) near equilibrium or nonequilibrium
quasistationary QGP is made.Comment: 10page
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
OHS: OH-airglow Suppressor for the Subaru Telescope
This paper describes an OH-airglow Suppressor (OHS) for the infrared Nasmyth
focus of the Subaru telescope. OHS has the capability of eliminating 224
airglow-lines in the - and -bands, which are major sources of background
radiation at near-infrared wavelengths up to 2 m. Specifically, it is a
pre-optics system installed between the telescope and an infrared
camera/spectrograph (CISCO). The suppressor reduces sky background emissions to
1/25 and its throughput is 40%. As a result, the S/N gain achieved with OHS is
more than 1 mag compared to the typical spectroscopic approach. The limiting
magnitude measured during a test observing run was found to be = 21.1 mag
( = 210, S/N = 5) in the standard 4000 s exposure
sequence.Comment: 6 pages, 9 figures. Accepted for publication in PASJ(2001
Rolling Tachyon Solution in Vacuum String Field Theory
We construct a time-dependent solution in vacuum string field theory and
investigate whether the solution can be regarded as a rolling tachyon solution.
First, compactifying one space direction on a circle of radius R, we construct
a space-dependent solution given as an infinite number of *-products of a
string field with center-of-mass momentum dependence of the form e^{-b p^2/4}.
Our time-dependent solution is obtained by an inverse Wick rotation of the
compactified space direction. We focus on one particular component field of the
solution, which takes the form of the partition function of a Coulomb system on
a circle with temperature R^2. Analyzing this component field both analytically
and numerically using Monte Carlo simulation, we find that the parameter b in
the solution must be set equal to zero for the solution to approach a finite
value in the large time limit x^0\to\infty. We also explore the possibility
that the self-dual radius R=\sqrt{\alpha'} is a phase transition point of our
Coulomb system.Comment: 39 pages, 17 figures, v3: references adde
Chan-Paton factors and Higgsing from Vacuum String Field Theory
We give a description of open strings stretched between N parallel D-branes
in VSFT. We show how higgsing is generated as the branes are displaced: the
shift in the mass formula for on-shell states stretched between different
branes is due to a twist anomaly, a contribution localized at the midpoint.Comment: 20 pages, JHEP clas
The Perturbative Spectrum of the Dressed Sliver
We analyze the fluctuations of the dressed sliver solution found in a
previous paper, hep-th/0311198, in the operator formulation of Vacuum String
Field Theory. We derive the tachyon wave function and then analyze the higher
level fluctuations. We show that the dressing is responsible for implementing
the transversality condition on the massless vector. In order to consistently
deal with the singular mode we introduce a string midpoint regulator and
we show that it is possible to accommodate all the open string states among the
solutions to the linearized equations of motion. We finally show how the
dressing can give rise to the correct ratio between the energy density of the
dressed sliver and the brane tension computed via the three-tachyons-coupling.Comment: 52 pages, v2: comment added in sec. 5, v3: one appendix added,
comments added in introduction and conclusion, to appear on PR
Boundary states as exact solutions of (vacuum) closed string field theory
We show that the boundary states are idempotent B*B=B with respect to the
star product of HIKKO type closed string field theory. Variations around the
boundary state correctly reproduce the open string spectrum with the gauge
symmetry. We explicitly demonstrate it for the tachyonic and massless vector
modes. The idempotency relation may be regarded as the equation of motion of
closed string field theory at a possible vacuum.Comment: 30 pages, 2 figures, v3:regularization improve
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