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New Vacuum of Bethe Ansatz Solutions in Thirring Model

T. Fujita·M. Hiramoto·T. Homma·H. Takahashi
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Abstract

We find a new vacuum of the Bethe ansatz solutions in the massless Thirring model. This vacuum breaks the chiral symmetry and has the lower energy than the well-known symmetric vacuum energy. Further, we evaluate the energy spectrum of the one particle-one hole ($1p-1h$) states, and find that it has a finite gap. The analytical expressions for the true vacuum as well as for the lowest $1p-1h$ excited state are also found. Further, we examine the bosonization of the massless Thirring model and prove that the well-known procedure of bosonization of the massless Thirring model is incomplete because of the lack of the zero mode in the boson field.

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T. Fujita, M. Hiramoto, T. Homma, H. Takahashi. 2004-10-22. New Vacuum of Bethe Ansatz Solutions in Thirring Model. https://doi.org/10.1143/jpsj.74.1143

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