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Fluctuations and Energy Shifts in the Bethe Ansatz

N. Beisert·L. Freyhult
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Abstract

We study fluctuations and finite size corrections for the ferromagnetic thermodynamic limit in the Bethe ansatz for the Heisenberg XXX1/2 spin chain, which is the AdS/CFT dual of semiclassical spinning strings. For this system we derive the standard quantum mechanical formula which expresses the energy shift as a sum over fluctuation energies. As an example we apply our results to the simplest, one-cut solution of this system and derive its spectrum of fluctuations.

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N. Beisert, L. Freyhult. 2005-07-05. Fluctuations and Energy Shifts in the Bethe Ansatz. https://doi.org/10.1016/j.physletb.2005.07.015

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