92 research outputs found
The perfect magnetic conductor (PMC) Casimir piston in d+1 dimensions
Perfect magnetic conductor (PMC) boundary conditions are dual to the more
familiar perfect electric conductor (PEC) conditions and can be viewed as the
electromagnetic analog of the boundary conditions in the bag model for hadrons
in QCD. Recent advances and requirements in communication technologies have
attracted great interest in PMC's and Casimir experiments involving structures
that approximate PMC's may be carried out in the not too distant future. In
this paper, we make a study of the zero-temperature PMC Casimir piston in
dimensions. The PMC Casimir energy is explicitly evaluated by summing over
-dimensional Dirichlet energies where p ranges from 2 to inclusively.
We derive two exact -dimensional expressions for the Casimir force on the
piston and find that the force is negative (attractive) in all dimensions. Both
expressions are applied to the case of 2+1 and 3+1 dimensions. A spin-off from
our work is a contribution to the PEC literature: we obtain a useful
alternative expression for the PEC Casimir piston in 3+1 dimensions and also
evaluate the Casimir force per unit area on an infinite strip, a geometry of
experimental interest.Comment: 18 pages, 1 figure, to appear in Phys. Rev.
Spectral functions and their applications
We give an introduction to the heat kernel technique and zeta function. Two
applications are considered. First we derive the high temperature asymptotics
of the free energy for boson fields in terms of the heat kernel expansion and
zeta function. Another application is chiral anomaly for local (MIT bag)
boundary conditions.Comment: 11 pages, Latex2
Casimir energy of a dilute dispersive dielectric ball: realistic microscopic model
The Casimir energy of a dilute homogeneous nonmagnetic dielectric ball at
zero temperature is derived analytically within a microscopic realistic model
of dielectrics for an arbitrary physically possible frequency dispersion of
dielectric permittivity. Divergences are absent in calculations, a minimum
interatomic distance is a physical cut-off. Casimir surface force is proved to
be attractive. A physical definition of the Casimir energy is discussed.Comment: Latex 2e, 4 pages, 1 figure, to appear in Int. J. Mod. Phys. A [a
talk given at the Fifth Leipzig Workshop on Quantum Field Theory under the
Influence of External Conditions, September 10-14, 2001
Casimir energy of dielectric systems
A new formula for the Casimir energy of a dispersive dilute dielectric ball
is discussed. The formula for the Casimir energy of a polarizable particle
situated in a perfectly conducting wedge-shaped cavity is derived by a
path-integral coordinate space method in quantum field theory.Comment: Latex 2e, 4 pages, no figures, a talk given at the International
Meeting "Quantum Gravity and Spectral Geometry" (Naples, Italy, July 2-7,
2001
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