A remark on alpha vacua for quantum field theories on de Sitter space
arXiv:hep-th/0503022 · doi:10.1088/1126-6708/2005/05/063
Abstract
It is shown that the so-called $α$-vacua which have been proposed as candidates for states of free quantum fields on de Sitter space have infinitely strong fluctuations for typical observables as averaged renormalized energy momentum tensor.