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Combinatorial Bethe ansatz and ultradiscrete Riemann theta function with rational characteristics

Atsuo Kuniba·Reiho Sakamoto
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Abstract

The U_q(\hat{sl}_2) vertex model at q=0 with periodic boundary condition is an integrable cellular automaton in one-dimension. By the combinatorial Bethe ansatz, the initial value problem is solved for arbitrary states in terms of an ultradiscrete analogue of the Riemann theta function with rational characteristics.

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Atsuo Kuniba, Reiho Sakamoto. 2007-07-10. Combinatorial Bethe ansatz and ultradiscrete Riemann theta function with rational characteristics. https://doi.org/10.1007/s11005-007-0162-2

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