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Spectral densities and partition functions of modular quantum systems as derived from a central limit theorem

Michael Hartmann·Guenter Mahler·Ortwin Hess
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Abstract

Using a central limit theorem for arrays of interacting quantum systems, we give analytical expressions for the density of states and the partition function at finite temperature of such a system, which are valid in the limit of infinite number of subsystems. Even for only small numbers of subsystems we find good accordance with some known, exact results.

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Michael Hartmann, Guenter Mahler, Ortwin Hess. 2004-12-01. Spectral densities and partition functions of modular quantum systems as derived from a central limit theorem. https://doi.org/10.1007/s10955-004-4298-5

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