Hadamard property of the in and out states for Klein-Gordon fields on asymptotically static spacetimes

TL;DR

This paper proves the existence and Hadamard property of in and out states for the massive Klein-Gordon equation on asymptotically static spacetimes, using scattering theory methods.

Contribution

It establishes the Hadamard property of quantum states for Klein-Gordon fields on a broad class of spacetimes, extending previous results to asymptotically static geometries.

Findings

Existence of in and out states on asymptotically static spacetimes

Proof of the Hadamard property for these states

Application of scattering theory methods to quantum field theory

Abstract

We consider the massive Klein-Gordon equation on a class of asymptotically static spacetimes (in the long range sense) with Cauchy surface of bounded geometry. We prove the existence and Hadamard property of the in and out states constructed by scattering theory methods.