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On the definition of temperature in FPU systems

A. Carati·P. Cipriani·L. Galgani
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Abstract

It is usually assumed, in classical statistical mechanics, that the temperature should coincide, apart from a suitable constant factor, with the mean kinetic energy of the particles. We show that this is not the case for \FPU systems, in conditions in which energy equipartition between the modes is not attained. We find that the temperature should be rather identified with the mean value of the energy of the low frequency modes.

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A. Carati, P. Cipriani, L. Galgani. 2003-11-19. On the definition of temperature in FPU systems. https://doi.org/10.1023/b%3Ajoss.0000022378.52789.b6

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