29,661 research outputs found

### Quark rotation asymmetry and baryon magnetic moments

Quark rotation asymmetry is proposed in calculating baryon magnetic moments.
After taking into account interactions enforced on constituent quarks, assumed
to be linear and Coulomb potentials, respectively, and the quark rotation
asymmetry, we fit the theoretical values, based on two more hypotheses and
several other reasonable assumptions, of baryon magnetic moments with those
from experiments. The good fitting results show the necessity of the
consideration of quark rotation asymmetry within baryon.Comment: 7 pages, submitted to Nuovo Cimento

### A new hierarchy of avalanches observed in Bak-Sneppen evolution model

A new quantity, average fitness, is introduced in Bak-Sneppen evolution
model. Through this new quantity, a new hierarchy of avalanches is observed in
the evolution of Bak-Sneppen model. An exact gap equation, governing the
self-organization of the model, is presented. It is found that the
self-organized threshold of the new quantity can be exactly obtained. Two basic
exponents, avalanche distribution and avalanche dimension are given through
simulations of one- and two-dimensional Bak-Sneppen models. It is suggested
that this new quantity may be a good quantity in determining the emergence of
criticality.Comment: 6 pages, 4 figure

### The forget-remember mechanism for 2-state spreading

A new mechanism, the forget-remember mechanism, is proposed for studying the
spreading process in 2-state model. Such mechanism exhibits behaviors of
message spreading influenced by some kinds of functions about time and history
caring about the individuals of the spreading system, holding message or being
out of message. To demonstrate the mechanism, both linear and exponential forms
for forget-function and remember-function are simulated and show that a great
impact on the saturation of message-spreading and the relative phase
transformation.Comment: 4 pages, 3 figures, revtex

### Finite-Size Effects in Critical Phenomena from Mean Field Approach with $\phi^4$ Model

The finite-size effects in critical phenomena of a thin film system are
studied from a mean field (MF) approach with $\phi^4$ model for second-order
phase transition. The influence of boundary condition on the critical
properties are emphasized. Scaling functions for relative free-energy and
relative specific heat capacity are given.Comment: 10 pages, LaTeX, 4 figure in PS forma

### Hawking Radiation of a Non-stationary Kerr-Newman Black Hole: Spin-Rotation Coupling Effect

Hawking evaporation of Klein-Gordon and Dirac particles in a non-stationary
Kerr-Newman space-time is investigated by using a method of generalized
tortoise coordinate transformation. The location and the temperature of the
event horizon of a non-stationary Kerr-Newman black hole are derived. It is
shown that the temperature and the shape of the event horizon depend not only
on the time but also on the angle. However, the Fermionic spectrum of Dirac
particles displays a new spin-rotation coupling effect which is absent from
that of Bosonic distribution of scalar particles. The character of this effect
is its obvious dependence on different helicity states of particles spin-1/2.
PACS numbers: 04.70.Dy, 97.60.LfComment: 12 pages, revtex, no figure, to appear in Gen. Rel. Grav. 34 (2002)
No.

### No New Quantum Thermal Effect of Dirac Particles in a Charged Vaidya - de Sitter Black Hole

It is shown that Hawking radiation of Dirac particles does not exist for
$P_1, Q_2$ components but for $P_2, Q_1$ components in a charged Vaidya - de
Sitter black hole. Both the location and the temperature of the event horizon
change with time. The thermal radiation spectrum of Dirac particles is the same
as that of Klein-Gordon particles. Our result demonstrates that there is no new
quantum effect in the thermal radiation of Dirac particles in any spherically
symmetry black holes.Comment: 12pt revtex, 10 pages, no figure, accepted for IL Nuovo Cimento

### Generalized Laws of Black Hole Thermodynamics and Quantum Conservation Laws on Hawking Radiation Process

Four classical laws of black hole thermodynamics are extended from exterior
(event) horizon to interior (Cauchy) horizon. Especially, the first law of
classical thermodynamics for Kerr-Newman black hole (KNBH) is generalized to
those in quantum form. Then five quantum conservation laws on the KNBH
evaporation effect are derived in virtue of thermodynamical equilibrium
conditions. As a by-product, Bekenstein-Hawking's relation $S=A/4$ is exactly
recovered.Comment: Latex, 8 pages, no figur

### Four Quantum Conservation Laws on Black Hole Equilibrium Radiation Process and Quantum Black Hole Entropy

The classical first law of thermodynamic for Kerr-Newmann black hole (KNBH)
is generalized to that in quantum form on event horizon. Then four quantum
conservation laws on the KNBH equilibrium radiation process are derived, and
Bekenstein-Hawking's relation S=A/4 is recovered. It can be argued that the
classical entropy of black hole arise from the quantum entropy of field quanta
or quasi-particles inside the hole.Comment: 10 Pages, in Latex, no figur

### Four Quantum Conservation Laws for Black Hole Stationary Equilibrium Radiation Processes

The classical first law of thermodynamics for a Kerr-Newman black hole (KNBH)
is generalized to a law in quantum form on the event horizon. Then four quantum
conservation laws on the KNBH equilibrium radiation process are derived. The
Bekenstein-Hawking relation ${\cal{S}}={\cal{A}}/4$ is exactly established. It
can be inferred that the classical entropy of black hole arises from the
quantum entropy of field quanta or quasi-particles inside the hole.Comment: 7 pages, no figure, Revtex in 12p

### A New Perturbation Theory of Finite-Size Effects Near Critical Point

A new perturbation theory is proposed for studying finite-size effects near
critical point of the $\phi^4$ model with a one-component order parameter. The
new approach is based on the techniques of generating functional and functional
derivative with respect to external source field and can be used for
temperatures both above and below the critical point of the bulk system. It is
shown that this approach is much simpler comparing with available perturbation
theories. Particularly, this new method avoids renormalization in calculating
many physical quantities such as correlation functions etc..Comment: 9 pages, in revte

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