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arXiv · 2409.08696

Many-body density of states of bosonic and fermionic gases: a combinatorial approach

Carolyn Echter·Georg Maier·Juan-Diego Urbina·Caio Lewenkopf·Klaus Richter
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Abstract

We use a combinatorial approach to obtain exact expressions for the many-body density of states of fermionic and bosonic gases with equally spaced single-particle spectra. We identify a mapping that reveals a remarkable property, namely, fermionic and bosonic gases have the same many-body density of states, up to a shift corresponding to ground state energy. Additionally, we show that there is a regime, comprising the validity range of the Bethe approximation, where the many-body density of states becomes independent of the number of particles.

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Carolyn Echter, Georg Maier, Juan-Diego Urbina, Caio Lewenkopf, Klaus Richter. 2024-09-13. Many-body density of states of bosonic and fermionic gases: a combinatorial approach. https://doi.org/10.1088/1751-8121/adae68

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