31,466 research outputs found
Energy diffusion in frustrated quantum spin chains exhibiting Gaussian orthogonal ensemble level statistics
Frustrated quantum spin chains with the next-nearest-neighbor (NNN)
couplings are typically deterministic many-body systems exhibiting Gaussian
orthogonal ensemble (GOE) spectral statistics. We investigate energy diffusion
for these spin chains in the presence of a periodically oscillating magnetic
field. Diffusion coefficients are found to obey the power law with respect to
both the field strength and driving frequency with its power varying depending
on the linear response and non-perturbative regimes. The widths of the linear
response and the non-perturbative regimes depend on the strength of
frustrations. We have also elucidated a mechanism for oscillation of energy
diffusion in the case of weakened frustrations.Comment: 6 pages, 6 figure
Thermodynamics of Extended Bodies in Special Relativity
Relativistic thermodynamics is generalized to accommodate four dimensional
rotation in a flat spacetime. An extended body can be in equilibrium when its
each element moves along a Killing flow. There are three types of basic Killing
flows in a flat spacetime, each of which corresponds to translational motion,
spatial rotation, and constant linear acceleration; spatial rotation and
constant linear acceleration are regarded as four dimensional rotation.
Translational motion has been mainly investigated in the past literature of
relativistic thermodynamics. Thermodynamics of the other two is derived in the
present paper.Comment: 8 pages, no figur
The quasi-classical model of the spherical configuration in general relativity
We consider the quasi-classical model of the spin-free configuration on the
basis of the self-gravitating spherical dust shell in General Relativity. For
determination of the energy spectrum of the stationary states on the basis of
quasi-classical quantization rules it is required to carry out some
regularization of the system. It is realized by an embedding of the initial
system in the extended system with rotation. Then, the stationary states of the
spherical shells are S-states of the system with the intrinsic momentum. The
quasi-classical treatment of a stability of the configuration is associated
with the Langer modification of a square of the quantum mechanical intrinsic
momentum. It gives value of critical bare mass of the shell determining
threshold of stability. For the shell with the bare mass smaller or equal to
the Planck's mass, the energy spectra of bound states are found. We obtain the
expression for tunneling probability of the shell and construct the
quasi-classical model of the pair creation and annihilation of the shells.Comment: 22 pages, sprocl.sty, 3 figure
Quantitative Cytological Studies on Thymic Lymphoid Cells in Normal, Preleukaemic and Leukaemic Mice
Relativistic Equilibrium Distribution by Relative Entropy Maximization
The equilibrium state of a relativistic gas has been calculated based on the
maximum entropy principle. Though the relativistic equilibrium state was long
believed to be the Juttner distribution, a number of papers have been published
in recent years proposing alternative equilibrium states. However, some of
these papers do not pay enough attention to the covariance of distribution
functions, resulting confusion in equilibrium states. Starting from a fully
covariant expression to avoid this confusion, it has been shown in the present
paper that the Juttner distribution is the maximum entropy state if we assume
the Lorentz symmetry.Comment: Six pages, no figure
Transmission and Reflection in the Stadium Billiard: Time-dependent asymmetric transport
We investigate the transmission and reflection survival probabilities for the
chaotic stadium billiard with two holes placed asymmetrically. Classically,
these distributions are shown to have algebraic or exponential decays depending
on the choice of injecting hole and exact expressions are given for the first
time and confirmed numerically. As there is no reported quantum theoretical or
experimental analogue we propose a model for experimental observation of the
asymmetric transport using semiconductor nano-structures and comment on the
relevant quantum time-scales.Comment: 4 pages, 4 figure
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