115,703 research outputs found
Thermodynamical Properties and Quasi-localized Energy of the Stringy Dyonic Black Hole Solution
In this article, we calculate the heat flux passing through the horizon and the difference of energy between the Einstein and
M{\o}ller prescription within the region , in which is the region
between outer horizon and inner horizon , for the
modified GHS solution, KLOPP solution and CLH solution. The formula . E_{\rm
Einstein}|_{\cal M} = . E_{\rm M{\o}ller}|_{\cal M} - \sum_{\partial {\cal M}}
{\bf TS}$ is obeyed for the mGHS solution and the KLOPP solution, but not for
the CLH solution. Also, we suggest a RN-like stringy dyonic black hole
solution, which comes from the KLOPP solution under a dual transformation, and
its thermodynamical properties are the same as the KLOPP solution
A scattering theory of ultrarelativistic solitons
We construct a perturbative framework for understanding the collision of
solitons (more precisely, solitary waves) in relativistic scalar field
theories. Our perturbative framework is based on the suppression of the
space-time interaction area proportional to , where is the
relative velocity of an incoming solitary wave and . We calculate the leading order results for collisions of (1+1) dimensional
kinks in periodic potentials, and provide explicit, closed form expressions for
the phase shift and the velocity change after the collisions. We find excellent
agreement between our results and detailed numerical simulations. Crucially,
our perturbation series is controlled by a kinematic parameter, and hence not
restricted to small deviations around integrable cases such as the Sine-Gordon
model.Comment: v3: 43 pages, 10 figures, references added, matches version accepted
for publication in PR
Energy Distribution in 2d Stringy Black Hole Backgrounds
We utilize Moller's and Einstein's energy-momentum complexes in order to
explicitly evaluate the energy distributions associated with the
two-dimensional "Schwarzschild" and "Reissner-Nordstrom" black hole
backgrounds. While Moller's prescription provides meaningful physical results,
Einstein's prescription fails to do so in the aforementioned gravitational
backgrounds. These results hold for all two-dimensional static black hole
geometries. The results obtained within this context are exploited in order
Seifert's hypothesis to be investigated.Comment: 17 pages, LaTeX, v2: acknowledgements added, to appear in
Int.J.Mod.Phys.
Probing the low-x structure of nuclear matter with diffractive hadron production in pA collisions
We argue that hadron production in coherent diffraction of proton on a heavy
nucleus provides a very sensitive probe of the low-x QCD dynamics. This process
probes the BFKL dynamics in proton and the non-linear gluon evolution in
nucleus. We calculate the diffractive hadron production cross sections in the
RHIC and LHC kinematic regions. To study the nuclear effects we introduce the
diffractive nuclear modification factor. We show that unlike the nuclear
modification factor for inclusive hadron production that has a very interesting
dynamics at RHIC but is expected to be almost completely saturated at the LHC,
the nuclear modification factor for diffractive production exhibits a
non-trivial behavior both at RHIC and LHC.Comment: 18 pages, 7 figure
Landscape Predictions from Cosmological Vacuum Selection
In BP models with hundreds of fluxes, we compute the effects of cosmological
dynamics on the probability distribution of landscape vacua. Starting from
generic initial conditions, we find that most fluxes are dynamically driven
into a different and much narrower range of values than expected from landscape
statistics alone. Hence, cosmological evolution will access only a tiny
fraction of the vacua with small cosmological constant. This leads to a host of
sharp predictions. Unlike other approaches to eternal inflation, the
holographic measure employed here does not lead to "staggering", an excessive
spread of probabilities that would doom the string landscape as a solution to
the cosmological constant problem.Comment: 15 pages, 6 figures, v4 prd format, minor editin
Photodetachment of H near a partial reflecting surface
Theoretical and interpretative study on the subject of photodetachment of
H near a partial reflecting surface is presented, and the absorption
effect of the surface is investigated on the total and differential cross
sections using a theoretical imaging method. To understand the absorption
effect, a reflection parameter is introduced as a multiplicative factor to
the outgoing detached-electron wave of H propagating toward the wall. The
reflection parameter measures, how much electron wave would reflect from the
surface; K=0 corresponds to no reflection and K=1 corresponds to the total
reflection.Comment: 8 pages, 4 figure
The Energy of the Gamma Metric in the M{\o}ller Prescription
We obtain the energy distribution of the gamma metric using the
energy-momentum complex of M{\o}ller. The result is the same as obtained by
Virbhadra in the Weinberg prescription
Gluon recombination in high parton density QCD: inclusive pion production
We argue that the collinear factorization of the fragmentation functions in
high energy hadron and nuclei collisions breaks down at transverse momenta kT <
Qs/g due to high parton densities in the colliding hadrons and/or nuclei. We
calculate, at next-to-leading order in projectile parton density and to all
orders in target parton density, the double-inclusive cross section for
production of a pair of gluons in the scalar J^(PC)=0^(++) channel. Using the
low energy theorems of QCD we find the inclusive cross section for pi-meson
production.Comment: 24 pages, 5 figure
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