Functional integral with "phi^4" term in the action beyond standard perturbative methods
arXiv:hep-th/0503235
Abstract
We propose the another, in principe nonperturbative, method of the evaluatiom of the Wiener functional integral for "phi^4" term in the action. We find the "generalized" Gelfand-Yaglom differential equation implying the functional integral in the continuum limit.
We clarify the proofs of the formulas, add a discussions of the mathematical steps