Log-concave functions and convex interaction terms for quantised fields
Jan Tarski · Journal of Physics A Mathematical and General · 1977
One considers those models of quantised fields for which the interaction Hamiltonians, with counter terms included, are convex functions of the fields. Some simple properties of these models (and of related ones) are obtained with the help of the theory of log-concave functions. In particular, the form of ground-state functionals is specified.