The behavior of a quantized meson field in a classical gravitational field is examined. Physical quantities such as the expectation value for the number of created mesons are represented in terms of a formal Green's function. They are computed explicitly for the case of a special space-independent gravitational field. The inadequacy of standard iteration procedures is discussed in an Appendix.

• Received 4 January 1960

DOI:https://doi.org/10.1103/PhysRev.118.1430