E. R. Bezerra de Mello, A. A. Saharian
In this paper we investigate the vacuum expectation values (VEVs) of the
field squared and the energy-momentum tensor associated with a massive scalar
quantum field induced by a generalized cosmic string in D-dimensional anti-de
Sitter (AdS) spacetime. In order to develop this analysis we evaluate the
corresponding Wightman function. As we shall observe, this function is
expressed as the sum of two terms: the first one corresponds to the Wightman
function in pure AdS bulk and the second one is induced by the presence of the
string. The second contribution is finite at coincidence limit and is used to
provide closed expressions for the parts in the VEVs of the field squared and
the energy-momentum tensor induced by the presence of the string. Because the
analysis of vacuum polarizations effects in pure AdS spacetime have been
developed in the literature, here we are mainly interested in the investigation
of string-induced effects. We show that the curvature of the background
spacetime has an essential influence on the VEVs at distances larger than the
curvature radius. In particular, at large distances the decay of the
string-induced VEVs is power-law for both massless and massive fields. The
string-induced parts vanish on the AdS boundary and they dominate the pure AdS
part for points near the AdS horizon.
View original:
http://arxiv.org/abs/1110.2129
No comments:
Post a Comment