Speaker
Description
We investigate the effects of background curvature, nontrivial topology and of a planar
boundary on the properties of the vacuum state for a charged scalar field. The
background geometry is locally dS with an arbitrary number of toroidally compact
dimensions. The planar boundary is perpendicular to one of infinite dimensions and on it
the charged scalar field obeys the Robin boundary condition. Along compact
dimensions general quasiperiodicity conditions are imposed and, in addition, the
presence of a constant gauge field is assumed. The latter induces Aharonov-Bohm-type
effect on the vacuum expectation values (VEVs) of physical observables. The periodicity
conditions imposed on fields along compact dimensions give rise to the modification of the
spectrum for normal modes and, related to this, the expectation values of physical
observables are changed. As important local characteristics of the vacuum state we
consider the VEVs of the field squared, energy-momentum tensor and of the current
density.
