Fermionic Casimir densities in anti-de Sitter spacetime
  The fermionic condensate and vacuum expectation value of the energy-momentum
tensor, for a massive fermionic field on the background of anti-de Sitter
spacetime, in the geometry of two parallel boundaries with bag boundary
conditions, are investigated. Vacuum expectation values, expressed as series
involving the eigenvalues of the radial quantum number, are neatly decomposed
into boundary-free, single-boundary-induced, and second-boundary-induced parts,
with the help of the generalized Abel-Plana summation formula. In this way, the
renormalization procedure is very conveniently reduced to the one corresponding
to boundary-free AdS spacetime. The boundary-induced contributions to the
fermionic condensate and to the vacuum expectation value of the energy density
are proven to be everywhere negative. The vacuum expectation values are
exponentially suppressed at distances from the boundaries much larger than the
curvature radius of the AdS space. Near the boundaries, effects related with
the curvature of the background spacetime are shown to be subdominant and, to
leading order, all known results for boundaries in the Minkowski bulk are
recovered. Zeta function techniques are successfully used for the evaluation of
the total vacuum energy in the region between the boundaries. It is proven that
the resulting interaction forces between them are attractive and that, for
large separations, they also decay exponentially. Finally, our results are
extended and explicitly translated to fermionic Casimir densities in braneworld
scenarios of Randall-Sundrum type.
