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arXiv · 1908.09423

Self-averaging of perturbation Hamiltonian density in perturbed spin systems

C. Itoi
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Abstract

It is shown that the variance of a perturbation Hamiltonian density vanishes in the infinite-volume limit of the perturbed spin systems with quenched disorder. This is proven in a simpler way and under less assumptions than before. A corollary of this theorem indicates the impossibility of non-spontaneous replica symmetry-breaking in disordered spin systems. The commutativity between the infinite-volume limit and the switched-off limit of a replica symmetry-breaking perturbation implies that the variance of the spin overlap vanishes in the replica symmetric Gibbs state.

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C. Itoi. 2019-08-26. Self-averaging of perturbation Hamiltonian density in perturbed spin systems. https://doi.org/10.1007/s10955-019-02408-y

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