| Université Paris 6 Pierre et Marie Curie | Université Paris 7 Denis Diderot | |
| CNRS U.M.R. 7599 | ||
| ``Probabilités et Modèles Aléatoires'' | ||
Auteur(s):
Code(s) de Classification MSC:
Résumé: We study the fluctuations of the free energy and overlaps of $n$ replicas for the $p$-spin Sherrington-Kirkptarick and Hopfield models of spin glasses in the high temperature phase. For the first model we show that at all inverse temperatures $\beta$ smaller than Talagrand's bound $\beta_p$ the free energy on the scale $N^{1-(p-2)/2}$ converges to a Gaussian law with zero mean and variance $\b^4 p!/2$; and that the law of the overlaps $\s\cdot \s'=\sum_{i=1}^{N}\s_i\s'_i$ of $n$ replicas on the scale $\sqrt{N}$ under the product of Gibbs measures is asymptotically the one of $n(n-1)/2$ independent standard Gaussian random variables. For the second model we prove that for all $\beta$ and the load of the memory $t$ with $\beta(1+\sqrt{t})<1$ the law of the overlaps of $n$ replicas on the scale $\sqrt{N}$ under the product of Gibbs measures is asymptotically the one of $n(n-1)/2$ independent Gaussian random variables with zero mean and variance $(1-t\b^2(1-\b)^{-2})^{-1}$.
Mots Clés: Spin glasses ; Sherrington-Kirkpatrick model ; $p$-spin model ;
Hopfield model ; overlap ; free energy ; martingales
Date: 2003-11-04
Prépublication numéro: PMA-860