1,518,308 research outputs found
Energy and Mass Generation
Modifications in the energy momentum dispersion laws due to a noncommutative
geometry, have been considered in recent years. We examine the oscillations of
extended objects in this perspective and find that there is now a "generation"
of energy.Comment: 13 pages Late
High Frequency Dynamics and Third Cumulant of Quantum Noise
The existence of the third cumulant of voltage fluctuations has
demonstrated the non-Gaussian aspect of shot noise in electronic transport.
Until now, measurements have been performed at low frequency, \textit{i.e.} in
the classical regime where voltage fluctuations arise
from charge transfer process. We report here the first measurement of at
high frequency, in the quantum regime . In this
regime, experiment cannot be seen as a charge counting statistics problem
anymore. It raises central questions of the statistics of quantum noise: 1) the
electromagnetic environment of the sample has been proven to strongly influence
the measurement, through the possible modulation of the noise of the sample.
What happens to this mechanism in the quantum regime? 2) For , the noise is due to zero point fluctuations and keeps its equilibrium
value: with the conductance of the sample. Therefore,
is independent of the bias voltage and no photon is emitted by the
conductor. Is it possible, as suggested by some theories, that in
this regime? With regard to these questions, we give theoretical and
experimental answers to the environmental effects showing that they involve
dynamics of the quantum noise. Using these results, we investigate the question
of the third cumulant of quantum noise in the a tunnel junction
Spread of \u3ci\u3eAcentria Ephemerella\u3c/i\u3e (Lepidoptera: Pyralidae) in Central North America
The aquatic moth, Acentria ephemerella, was first reported from North America in 1927. Recent records from widespread localities in central North America indicate that the range of this European introduction continues to expand. The moth is well established in the western Great Lakes region and is recorded west to the Missouri River valley in Iowa
Rocket plume properties measured in space simulators
Molecular sink facility and 25-foot space simulator have been used to distinguish nature of exhaust plumes from nozzles with relatively large internal boundary layer flow. Plume density has been measured by electron beam/photomultiplier system
Lightweight graphite/polyimide panels
Panels are constructed of honeycombed polyimide/graphite core covered with thin face sheet of same material. Fabrication is based on extension of thin-gage graphite technology and modification of glass filament polyimide honeycomb techniques
Elements of Design for Containers and Solutions in the LinBox Library
We describe in this paper new design techniques used in the \cpp exact linear
algebra library \linbox, intended to make the library safer and easier to use,
while keeping it generic and efficient. First, we review the new simplified
structure for containers, based on our \emph{founding scope allocation} model.
We explain design choices and their impact on coding: unification of our matrix
classes, clearer model for matrices and submatrices, \etc Then we present a
variation of the \emph{strategy} design pattern that is comprised of a
controller--plugin system: the controller (solution) chooses among plug-ins
(algorithms) that always call back the controllers for subtasks. We give
examples using the solution \mul. Finally we present a benchmark architecture
that serves two purposes: Providing the user with easier ways to produce
graphs; Creating a framework for automatically tuning the library and
supporting regression testing.Comment: 8 pages, 4th International Congress on Mathematical Software, Seoul :
Korea, Republic Of (2014
Induced photon emission from quark jets in ultrarelativistic heavy-ion collisions
We study the induced photon bremsstrahlung from a fast quark produced in
AA-collisions due to multiple scattering in quark-gluon plasma. For RHIC and
LHC conditions the induced photon spectrum is sharply peaked at photon energy
close to the initial quark energy. In this region the contribution of the
induced radiation to the photon fragmentation function exceeds the ordinary
vacuum radiation. Contrary to previous analyses our results show that at RHIC
and LHC energies the final-state interaction effects in quark-gluon plasma do
not suppress the direct photon production, and even may enhance it at p_{T}
about 5-15 GeV.Comment: 11 pages, 4 figure
Index theory and dynamical symmetry enhancement of M-horizons
We show that near-horizon geometries of 11-dimensional supergravity preserve
an even number of supersymmetries. The proof follows from Lichnerowicz type
theorems for two horizon Dirac operators, the field equations and Bianchi
identities, and the vanishing of the index of a Dirac operator on the
9-dimensional horizon sections. As a consequence of this, we also prove that
all M-horizons with non-vanishing fluxes admit a sl(2,R) subalgebra of
symmetries.Comment: Minor typos corrected. 22 pages, latex. Repeats equations and
descriptions from arXiv:1207.708
Pseudoscalar and vector meson form factors from lattice QCD
We present a study of the pseudoscalar and vector meson form factors,
calculated using the Fat-Link Irrelevant Clover (FLIC) action in the framework
of Quenched Lattice QCD. Of particular interest is the determination of a
negative quadrupole moment, indicating that the meson is not spherically
symmetric.Comment: 11 pages, 15 figures, 9 table
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