5 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 $\delta$ 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

### Effective Electromagnetic Lagrangian at Finite Temperature and Density in the Electroweak Model

Using the exact propagators in a constant magnetic field, the effective
electromagnetic Lagrangian at finite temperature and density is calculated to
all orders in the field strength B within the framework of the complete
electroweak model, in the weak coupling limit. The partition function and free
energy are obtained explicitly and the finite temperature effective coupling is
derived in closed form. Some implications of this result, potentially
interesting to astrophysics and cosmology, are discussed.Comment: 14 pages, Revtex

### Casimir effect of electromagnetic field in Randall-Sundrum spacetime

We study the finite temperature Casimir effect on a pair of parallel
perfectly conducting plates in Randall-Sundrum model without using scalar field
analogy. Two different ways of interpreting perfectly conducting conditions are
discussed. The conventional way that uses perfectly conducting condition
induced from 5D leads to three discrete mode corrections. This is very
different from the result obtained from imposing 4D perfectly conducting
conditions on the 4D massless and massive vector fields obtained by decomposing
the 5D electromagnetic field. The latter only contains two discrete mode
corrections, but it has a continuum mode correction that depends on the
thicknesses of the plates. It is shown that under both boundary conditions, the
corrections to the Casimir force make the Casimir force more attractive. The
correction under 4D perfectly conducting condition is always smaller than the
correction under the 5D induced perfectly conducting condition. These
statements are true at any temperature.Comment: 20 pages, 4 figure

### The Casimir effect for parallel plates in the spacetime with a fractal extra compactified dimension

The Casimir effect for massless scalar fields satisfying Dirichlet boundary
conditions on the parallel plates in the presence of one fractal extra
compactified dimension is analyzed. We obtain the Casimir energy density by
means of the regularization of multiple zeta function with one arbitrary
exponent. We find a limit on the scale dimension like $\delta>1/2$ to keep the
negative sign of the renormalized Casimir energy which is the difference
between the regularized energy for two parallel plates and the one with no
plates. We derive and calculate the Casimir force relating to the influence
from the fractal additional compactified dimension between the parallel plates.
The larger scale dimension leads to the greater revision on the original
Casimir force. The two kinds of curves of Casimir force in the case of
integer-numbered extra compactified dimension or fractal one are not
superposition, which means that the Casimir force show whether the
dimensionality of additional compactified space is integer or fraction.Comment: 9 pages, 3 figure