52 research outputs found
Influence of a magnetic fluxon on the vacuum energy of quantum fields confined by a bag
We study the simultaneous influence of boundary conditions and external
fields on quantum fluctuations by considering vacuum zero-point energies for
quantum fields in the presence of a magnetic fluxon confined by a bag, circular
and spherical for bosons and circular for fermions. The Casimir effect is
calculated in a generalized cut-off regularization after applying zeta-function
techniques to eigenmode sums and using recent techniques about Bessel zeta
functions at negative arguments
Complete zeta-function approach to the electromagnetic Casimir effect for spheres and circles
A technique for evaluating the electromagnetic Casimir energy in situations
involving spherical or circular boundaries is presented. Zeta function
regularization is unambiguously used from the start and the properties of
Bessel and related zeta functions are central. Nontrivial results concerning
these functions are given. While part of their application agrees with previous
knowledge, new results like the zeta-regularized electromagnetic Casimir energy
for a circular wire are included.Comment: accepted in Ann. Phy
Attractive Casimir effect in an infrared modified gluon bag model
In this work, we are motivated by previous attempts to derive the vacuum
contribution to the bag energy in terms of familiar Casimir energy calculations
for spherical geometries. A simple infrared modified model is introduced which
allows studying the effects of the analytic structure as well as the geometry
in a clear manner. In this context, we show that if a class of infrared
vanishing effective gluon propagators is considered, then the renormalized
vacuum energy for a spherical bag is attractive, as required by the bag model
to adjust hadron spectroscopy.Comment: 7 pages. 1 figure. Accepted for publication in Physical Review D.
Revised version with improved analysis and presentation, references adde
Dirac fields in the background of a magnetic flux string and spectral boundary conditions
We study the problem of a Dirac field in the background of an Aharonov-Bohm
flux string. We exclude the origin by imposing spectral boundary conditions at
a finite radius then shrinked to zero. Thus, we obtain a behaviour of
eigenfunctions which is compatible with the self-adjointness of the radial
Hamiltonian and the invariance under integer translations of the reduced flux.
After confining the theory to a finite region, we check the consistency with
the index theorem, and evaluate its vacuum fermionic number and Casimir energy.Comment: 9 pages, 1 figure Two references added To be published in
International Journal of Modern Physics
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