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arXiv · 2103.06207

On the mean-field equations for ferromagnetic spin systems

Christian Brennecke·Per von Soosten
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Abstract

We derive mean-field equations for a general class of ferromagnetic spin systems with an explicit error bound in finite volumes. The proof is based on a link between the mean-field equation and the free convolution formalism of random matrix theory, which we exploit in terms of a dynamical method. We present three sample applications of our results to Ka\'{c} interactions, randomly diluted models, and models with an asymptotically vanishing external field.

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Christian Brennecke, Per von Soosten. 2021-03-10. On the mean-field equations for ferromagnetic spin systems. https://doi.org/10.1007/s11005-021-01450-w

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