Correlation asymptotics of classical lattice spin systems with nonconvex Hamilton function at low temperature (Q1586906)

The authors study the correlation function of lattice field theory by means of Witten's deformed Laplacian [see also \textit{J. Sjöstrand}, St. Petersbg. Math. J. 8, 123-147 (1997; Zbl 0877.35084)]. For sufficiently low temperature one derives an estimate for the spectral gap of a certain Witten Laplacian, one proves exponential decay of the two-point correlation function and one derives its asymptotics as the distance between spin sites becomes large.