On renormalisation of λϕ⁴field theory in curved space-time. II

Abstract

For pt.I see ibid., vol.13, p.901 (1980). An explicit renormalisation of all second-order physical processes occurring in lambda phi 4 field theory in conformally flat space-time, including vacuum-to-vacuum processes, is performed. Although divergences dependent on the definition of the vacuum state appear in some Feynman diagrams, physical amplitudes obtained by summing all diagrams which contribute to a single physical process are independent of these divergences. Consequently, the theory remains renormalisable in curved space-time, at least to second order in lambda . Renormalisations of the mass m, the coupling constant lambda and the constant xi which couples the field to the Ricci scalar are required to make two- and four-particle creation amplitudes finite.