Computation of functional integrals in problems of quantum and statistical physics Original Research Article

A method for computation of characteristics in quantum and statistical physics is described. This method is based on the representation of the matrix element of the evolution operator in Euclidean metrics in the form of a functional integral with a certain measure in the corresponding space and on the use of approximation formulas which we constructed for this kind of integral. No simplifying assumptions such as semiclassical approximation, no introduction of “short-time” propagators are necessary. The method is applied to the numerical study of some potential nuclear models and to investigation of the topological effects in gauge theories. The comparison of results with experimental data and with the values obtained by other authors are presented.