64,865 research outputs found
The Casimir effect for parallel plates at finite temperature in the presence of one fractal extra compactified dimension
We discuss the Casimir effect for massless scalar fields subject to the
Dirichlet boundary conditions on the parallel plates at finite temperature in
the presence of one fractal extra compactified dimension. We obtain the Casimir
energy density with the help of the regularization of multiple zeta function
with one arbitrary exponent and further the renormalized Casimir energy density
involving the thermal corrections. It is found that when the temperature is
sufficiently high, the sign of the Casimir energy remains negative no matter
how great the scale dimension is within its allowed region. We derive
and calculate the Casimir force between the parallel plates affected by the
fractal additional compactified dimension and surrounding temperature. The
stronger thermal influence leads the force to be stronger. The nature of the
Casimir force keeps attractive.Comment: 14 pages, 2 figure
The Luminosity - E_p Relation within Gamma--Ray Bursts and Implications for Fireball Models
Using a sample of 2408 time-resolved spectra for 91 BATSE gamma-ray bursts
(GRBs) presented by Preece et al., we show that the relation between the
isotropic-equivalent luminosity (L_iso) and the spectral peak energy (E_p) in
the cosmological rest frame, L_iso \propto E_p^2, not only holds within these
bursts, but also holds among these GRBs, assuming that the burst rate as a
function of redshift is proportional to the star formation rate. The possible
implications of this relation for the emission models of GRBs are discussed. We
suggest that both the kinetic-energy-dominated internal shock model and the
magnetic-dissipation-dominated external shock model can well interpret this
relation. We constrain the parameters for these two models, and find that they
are in a good agreement with the parameters from the fittings to the afterglow
data (abridged).Comment: 3 pages plus 5 figures, emulateapj style, accepted for publication in
ApJ Letter
The Additional Symmetries for the BTL and CTL Hierarchies
The Toda lattice (TL) hierarchy was first introduced by K.Ueno and K.Takasaki
in \cite{uenotaksasai} to generalize the Toda lattice equations\cite{toda}.
Along the work of E. Date, M. Jimbo, M. Kashiwara and T. Miwa \cite{DJKM} on
the KP hierarchy, K.Ueno and K.Takasaki in \cite{uenotaksasai} develop the
theory for the TL hierarchy: its algebraic structure, the linearization, the
bilinear identity, function and so on. Also the analogues of the B and C
types for the TL hierarchy, i.e. the BTL and CTL hierarchies, are considered in
\cite{uenotaksasai}, which are corresponding to infinite dimensional Lie
algebras and respectively. In this
paper, we will focus on the study of the additional symmetries for the BTL and
CTL hierarchies.Comment: 13 page
Strategies for protecting intellectual property when using CUDA applications on graphics processing units
Recent advances in the massively parallel computational abilities of graphical processing units (GPUs) have increased their use for general purpose computation, as companies look to take advantage of big data processing techniques. This has given rise to the potential for malicious software targeting GPUs, which is of interest to forensic investigators examining the operation of software. The ability to carry out reverse-engineering of software is of great importance within the security and forensics elds, particularly when investigating malicious software or carrying out forensic analysis following a successful security breach. Due to the complexity of the Nvidia CUDA (Compute Uni ed Device Architecture) framework, it is not clear how best to approach the reverse engineering of a piece of CUDA software. We carry out a review of the di erent binary output formats which may be encountered from the CUDA compiler, and their implications on reverse engineering. We then demonstrate the process of carrying out disassembly of an example CUDA application, to establish the various techniques available to forensic investigators carrying out black-box disassembly and reverse engineering of CUDA binaries. We show that the Nvidia compiler, using default settings, leaks useful information. Finally, we demonstrate techniques to better protect intellectual property in CUDA algorithm implementations from reverse engineering
Radiative lepton flavor violating decays in the Randall Sundrum background with localized leptons
We study the radiative lepton flavor violating l_i -> l_j\gamma decays in the
two Higgs doublet model, respecting the Randall Sundrum scenario and estimate
the contributions of the KK modes of left (right) handed charged lepton
doublets (singlets) on the branching ratios. We observe that the branching
ratios are sensitive to the contributions of the charged lepton KK modes.Comment: 23 pages, 10 figures, 2 table
Time-resolved measurement of single pulse femtosecond laser-induced periodic surface structure formation
Time-resolved diffraction microscopy technique has been used to observe the
formation of laser-induced periodic surface structures (LIPSS) from the
interaction of a single femtosecond laser pulse (pump) with a nano-scale groove
mechanically formed on a single-crystal Cu substrate. The interaction dynamics
(0-1200 ps) was captured by diffracting a time-delayed, frequency-doubled pulse
from nascent LIPSS formation induced by the pump with an infinity-conjugate
microscopy setup. The LIPSS ripples are observed to form sequentially outward
from the groove edge, with the first one forming after 50 ps. A 1-D analytical
model of electron heating and surface plasmon polariton (SPP) excitation
induced by the interaction of incoming laser pulse with the groove edge
qualitatively explains the time-evloution of LIPSS formation.Comment: 4 pages, 5 figure
- …