2,045 research outputs found
Casimir Densities for a Massive Fermionic Quantum Field in a Global Monopole Background with Spherical Boundary
We investigate the vacuum expectation value of the energy-momentum tensor
associated with a massive fermionic field obeying the MIT bag boundary
condition on a spherical shell in the global monopole spacetime. The asymptotic
behavior of the vacuum densities is investigated near the sphere center and
surface, and at large distances from the sphere. In the limit of strong
gravitational field corresponding to small values of the parameter describing
the solid angle deficit in global monopole geometry, the sphere-induced
expectation values are exponentially suppressed.Comment: 8 pages, 4 figures, 6th Alexander Friedmann International Seminar on
Gravitation and Cosmolog
Electrostatic in Reissner-Nordstrom space-time with a conical defect
We calculate the electrostatic potential generated by a point charge in the
space-time of Reissner-Nordstrom with a conical defect. An expression for the
self-energy is also presented.Comment: 7 pages, LATEX fil
Euclidean Scalar Green Function in a Higher Dimensional Global Spacetime
We construct the explicit Euclidean scalar Green function associated with a
massless field in a higher dimensional global monopole spacetime, i.e., a
-spacetime with which presents a solid angle deficit. Our
result is expressed in terms of a infinite sum of products of Legendre
functions with Gegenbauer polynomials. Although this Green function cannot be
expressed in a closed form, for the specific case where the solid angle deficit
is very small, it is possible to develop the sum and obtain the Green function
in a more workable expression. Having this expression it is possible to
calculate the vacuum expectation value of some relevant operators. As an
application of this formalism, we calculate the renormalized vacuum expectation
value of the square of the scalar field, , and the
energy-momentum tensor, , for the global monopole
spacetime with spatial dimensions and .Comment: 18 pages, LaTex format, no figure
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