On the quantum Feynmann-Kac formula
Luigi Accardi
Abstract
The Feynman--Kac formula is a technique, based on functional integration, which allows to perturb a markovian (i.e. positivity and identity preserving) semi--group $\\exp tH$ with suitable continuity properties into a new positivity preserving semi--group whose formal generator has the form $H+V$ and to obtain a fairly explicit representation of the latter in terms of a functional integral.