S-matrix in de Sitter spacetime from general boundary quantum field theory

Understand

A new quantization scheme for a massive scalar field in de Sitter spacetime is proposed, based on the general boundary formulation of quantum field theory.

• We show that the general interacting theory can be consistently described in terms of the S-matrix for spatial asymptotic states.
• The new S-matrix results to be equivalent to the standard one in situations where both apply.
• This is due to the existence of an isomorphism between the corresponding asymptotic state spaces.