Local thermal observables in spatially open FRW spaces

Abstract

Certain local thermal observables are considered in well-known examples of spatially open FRW spaces: Milne, open de Sitter and anti--de Sitter as well as Einstein static universes. Another value for fixing the ambiguity in defining the Wick square and, hence, the local temperature is motivated in the last example. Physical consequences of that choice are discussed for static and conformal vacua in those spaces.