MG12 - Talk detail
 

Back to previous page

 Participant 

Institution

Session

Talk

Abstract

Group Averaging for quantum fields in de Sitter

Perturbative gravity about global de Sitter space is subject to linearization-stability constraints. Such constraints imply that quantum states of matter fields couple consistently to gravity only if the matter state has vanishing de Sitter charges; i.e. only if the state is invariant under the symmetries of de Sitter space. The usual Fock spaces for matter fields contain at most one de Sitter-invariant state (the vacuum); however, using group averaging techniques one can construct a new Hilbert space of de Sitter-invariant states. This talk will review recent work on group averaging for de Sitter quantum fields.

Interacting quantum fields in de Sitter

The study of quantum fields in de Sitter space offers a tractable model in which to investigate many of the conceptual issues that arise generically for quantum fields in curved spacetime. The study of free fields in de Sitter has taught us a great deal about issues such as the choice of vacuum, the definition and usefulness of the S-matrix, particle production, etc. Thus far studies of interacting fields in de Sitter have been fairly heuristic. The purpose of this talk is to present our recent study of interacting fields in de Sitter. We calculate propagators and Wightman functions in perturbative quantum field theory on a de Sitter background for various fields and interactions. Renormalizability, multi-particle effects, and IR behavior will be discussed.

Back to previous page