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Now showing items 2521-2540 of 2611
Cosmological perturbations: a new gauge-invariant approach
(arXiv, 2001)
A new gauge-invariant approach for describing cosmological perturbations is developed. It is based on a physically motivated splitting of the stress-energy tensor of the perturbation into two parts - the bare perturbation ...
Testing the Relativistic Effect of the Propagation of Gravity by Very Long Baseline Interferometry
(arXiv, 2001)
It is shown that the finite speed of gravity affects very-long baseline interferometric observations of quasars during the time of their line-of-sight close angular encounter with Jupiter. The next such event will take ...
Numerical Data Processing Simulation of Microarcsecond Classical and Relativistic Effects in Space Astrometry
(arXiv, 2000)
The accuracy of astrometric observations conducted via a space-borne optical interferometer orbiting the Earth is expected to approach a few microarcseconds. Data processing of such extremely high- precision measurements ...
Magnetic ordering in the spinel compound Li[Mn2-xLix]O4(x=0,0.04)
(American Institute of Physics, 2009)
The two B-site ions Mn3+ and Mn4+ in the stoichiometric spinel structure LiMn2O4 form a complex, columnar ordered pattern below the charge-ordering transition at room temperature. On further cooling to below 66 K, the ...
Sub-2 nm Size-Tunable High-Density Pt Nanoparticle Embedded Nonvolatile Memory
(Institute of Electrical and Electronics Engineers, 2009-12)
The charge-storage characteristics of a metal-oxide-semiconductor (MOS) structure containing size-tunable sub-2 nm Pt nanoparticles (NPs) between Al2O3 tunneling and capping oxide layers were studied. Significantly different ...
Nonlinear Quasiparticle Tunneling between Fractional Quantum Hall Edges
(American Physical Society, 2003)
Remarkable nonlinearities in the differential tunneling conductance between fractional quantum Hall edge states at a constriction are observed in the weak- backscattering regime. In the ν=1/3 state a peak develops as ...
Dynamics of extended spinning masses in a gravitational field
(American Physical Society, 2006)
We develop a first-order approximation method for the influence of spin on the motion of extended spinning test masses in a gravitational field. This approach is illustrated for approximately circular equatorial motion in ...
Toward a Nonlocal Theory of Gravitation
(arXiv, 2006)
The nonlocal theory of accelerated systems is extended to linear gravitational waves as measured by accelerated observers in Minkowski spacetime. The implications of this approach are discussed. In particular, the nonlocal ...
Nonlocal Dirac equation for accelerated observers
(American Physical Society, 2007)
The nonlocal theory of accelerated systems is extended to the propagation of Dirac particles. The implications of nonlocality for the phenomenon of spin-rotation coupling are discussed. The Lorentz-invariant nonlocal Dirac ...
Decaying dark energy in higher-dimensional gravity
(EDP Sciences, 2007)
Aims. We use data from observational cosmology to put constraints on higher-dimensional extensions of general relativity in which the effective four-dimensional dark-energy density (or cosmological “constant”) decays with ...
An Embedding for General Relativity and its Implications for New Physics
(arXiv, 2007)
We show that any solution of the 4D Einstein equations of general relativity in vacuum with a cosmological constant may be embedded in a solution of the 5D Ricci-flat equations with an effective 4D cosmological "constant" ...
Nonlocal Electrodynamics of Accelerated Systems
(arXiv, 2007)
Acceleration-induced nonlocality is discussed and a simple field theory of nonlocal electrodynamics is developed. The theory involves a pair of real parameters that are to be determined from observation. The implications ...
Nonlocal Transformations for Accelerated Observers
(arXiv, 2009)
According to the locality postulate of special relativity, the measurements of physical fields by accelerated observers at a given event in Minkowski spacetime are related to each other by the representations of the Lorentz ...
Physical signatures of discontinuities of the time-dependent exchange-correlation potential
(Royal Society of Chemistry, 2009)
The exact exchange-correlation (XC) potential in time-dependent density-functional theory (TDDFT) is known to develop steps and discontinuities upon change of the particle number in spatially confined regions or isolated ...
Time-dependent density-functional theory for electronic excitations in materials: basics and perspectives
(arXiv, 2008)
Time-dependent density-functional theory (TDDFT) is widely used to describe electronic excitations in complex finite systems with large numbers of atoms, such as biomolecules and nanocrystals. The first part of this paper ...
Optical and structural properties of ZnO films deposited on GaAs by pulsed laser deposition
(American Institute of Physics, 2000)
ZnO films were synthesized on GaAs substrates at different growth conditions by pulse laser deposition. High-purity (99.999%) oxygen was used as the ambient gas. The pressure of the ambient oxygen gas for ZnO film growth ...
Quasiparticle self-energy and many-body effective mass enhancement in a two-dimensional electron liquid
(American Physical Society, 2005)
Motivated by a number of recent experimental studies we have revisited the problem of the microscopic calculation of the quasiparticle self-energy and many-body effective mass enhancement in an unpolarized two- dimensional ...
Dynamical exchange-correlation potentials for the electron liquid in the spin channel
(American Physical Society, 2003)
The components of the exchange-correlation kernel tensor of an isotropic electron liquid in the spin channel have the structure f xc,2 L,T (q,v) ! q!0 A(v)/q21BL,T(v), where L denotes the longitudinal component and T the ...
Spin-resolved correlation kinetic energy of the spin-polarized electron gas
(American Physical Society, 2004)
We give an exact formula, based on differentiation with respect to the electron mass, for the spin resolution of the kinetic energy (KE) of a general many-electron system, including the correlation KE. We evaluate the ...
Spin Mass of an Electron Liquid
(American Physical Society, 2004)
We show that in order to calculate correctly the spin current carried by a quasiparticle in an electron liquid one must use an effective “spin mass” ms that is larger than both the band mass mb, which determines the charge ...