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No phase transition for Gaussian fields with bounded spins

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 نشر من قبل Pablo A. Ferrari
 تاريخ النشر 2007
  مجال البحث فيزياء
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Let a<b, Omega=[a,b]^{Z^d} and H be the (formal) Hamiltonian defined on Omega by H(eta) = frac12 sum_{x,yinZ^d} J(x-y) (eta(x)-eta(y))^2 where J:Z^dtoR is any summable non-negative symmetric function (J(x)ge 0 for all xinZ^d, sum_x J(x)<infty and J(x)=J(-x)). We prove that there is a unique Gibbs measure on Omega associated to H. The result is a consequence of the fact that the corresponding Gibbs sampler is attractive and has a unique invariant measure.



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