98-452 Kuelske C.
The continuous spin random field model: ferromagnetic ordering in $d\geq 3$ (425K, PS) Jun 16, 98
Abstract , Paper (src), View paper (auto. generated ps), Index of related papers

Abstract. We investigate the Gibbs-measures of ferromagnetically coupled continuous spins in double-well potentials subjected to a random field (our specific example being the $\phi^4$ theory), showing ferromagnetic ordering in $d\geq 3$ dimensions for weak disorder and large energy barriers. We map the random continuous spin distributions to distributions for an Ising-spin system by means of a single-site coarse-graining method described by local transition kernels. We derive a contour- representation for them with notably positive contour activities and prove their Gibbsianness. This representation is shown to allow for application of the discrete-spin renormalization group developed by Bricmont/Kupiainen implying the result in $d\geq 3$.

Files: 98-452.ps