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arXiv · 1104.5710

Anomalous Fisher-like zeros for the canonical partition function of noninteracting fermions

R. K. Bhaduri·A. MacDonald·W. van Dijk
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Abstract

Noninteracting fermions, placed in a system with a continuous density of states, may have zeros in the $N$-fermion canonical partition function on the positive real $β$ axis (or very close to it), even for a small number of particles. This results in a singular free energy, and instability in other thermal properties of the system. In the context of trapped fermions in a harmonic oscillator, these zeros are shown to be unphysical. By contrast, similar bosonic calculations with continuous density of states yield sensible results.Noninteracting fermions, placed in a system with a continuous density of states yield sensible results.

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R. K. Bhaduri, A. MacDonald, W. van Dijk. 2011-11-24. Anomalous Fisher-like zeros for the canonical partition function of noninteracting fermions. https://doi.org/10.1209/0295-5075%2F96%2F56003

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