On a Dynamical-Like Replica-Symmetry-Breaking Scheme for the Spin Glass

Considering the unphysical result obtained in the calculation of the free-energy cost for twisting the boundary conditions in a spin glass, we trace it to the negative multiplicities associated with the Parisi replica-symmetry breaking (RSB). We point out that a distinct RSB, that keeps positive multiplicities, was proposed long ago, in the spirit of an ultra-long time dynamical approach due to Sompolinsky. For an homogeneous bulk system, both RSB schemes are known to yield identical free energies and observables. However, using the dynamical RSB, we have recalculated the twist free energy at the mean-field level. The free-energy cost of this twist is, as expected, positive in that scheme, as it should be

TECHNIQUES DE RENORMALISATION DE LA THÉORIE DES CHAMPS ET DYNAMIQUE DES PHÉNOMÈNES CRITIQUES

La dynamique des phénomènes critiques telle qu'elle est décrite par les équations stochastiques de type Ginzburg-Landau dépendant du temps, avec ou sans loi de conservation, est étudiée par les techniques de renormalisation de la théorie des champs. Le cas des systèmes comportant un couplage mode-mode est brièvement abordé

Random fields and spin glasses: a field theory approach

Theory of magnetic systems for graduate students and researchers in statistical physics and basic field theory

Gaussian propagators for the Ising spin glass below Tc

As building blocks of a field theory to be constructed upon Parisi's mean field solution for an Ising spin glass, the complete set of the Gaussian propagators is given

Random fields and spin glasses: a field theory approach

Disordered magnetic systems enjoy non-trivial properties which are different and richer than those observed in their pure, non-disordered counterparts. These properties dramatically affect the thermodynamic behaviour and require specific theoretical treatment. This 2006 book deals with the theory of magnetic systems in the presence of frozen disorder, in particular paradigmatic and well-known spin models such as the Random Field Ising Model and the Ising Spin Glass. This is a unified presentation using a field theory language ..

Non-homogeneous mean field picture for spin-glasses

In this letter we perform quenched averages (without replicas) for spin-glass systems with local disorder. This allows a natural definition of a mean field theory. The mean fields relevant to spin-glasses are shown to be instantons

Quatrième Rencontre de Physique Statistique de Paris

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