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arXiv · 1909.00800

Bethe Ansatz for XXX chain with negative spin

Kun Hao·Dmitri Kharzeev·Vladimir Korepin
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Abstract

XXX spin chain with spin $s=-1$ appears as an effective theory of Quantum Chromodynamics. It is equivalent to lattice nonlinear Schroediger's equation: interacting chain of harmonic oscillators [bosonic]. In thermodynamic limit each energy level is a scattering state of several elementary excitations [lipatons]. Lipaton is a fermion: it can be represented as a topological excitation [soliton] of original [bosonic] degrees of freedom, described by the group $Z_2$ . We also provide the CFT description (including local quenches) and Yang-Yang thermodynamics of the model.

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Kun Hao, Dmitri Kharzeev, Vladimir Korepin. 2019-09-02. Bethe Ansatz for XXX chain with negative spin. https://doi.org/10.1142/s0217751x19501975

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