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arXiv · 2606.06277

A note on the 2D NLSM free energy

Yizhuang Liu
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Abstract

This note contains the perturbative computation of the 2D non-linear sigma model (NLSM) energy-density in a chemical potential $h$, at the fourth order in the coupling constant expansion. The result is in fully agreement with the $h\rightarrow \infty$ asymptotics extracted from the thermodynamical Bethe ansatz (TBA).

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Yizhuang Liu. 2026-06-04. A note on the 2D NLSM free energy. https://arxiv.org/abs/2606.06277

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