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arXiv · hep-th/9804205

Bosonized Massive N-flavor Schwinger Model

Yutaka Hosotani·Ramon Rodriguez
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Abstract

The massive N-flavor Schwinger model is analyzed by the bosonization method. The problem is reduced to the quantum mechanics of N degrees of freedom in which the potential needs to be self-consistently determined by its ground-state wave function and spectrum with given values of the $θ$ parameter, fermion masses, and temperature. Boson masses and fermion chiral condensates are evaluated. In the N=1 model the anomalous behavior is found at $θ\sim π$ and $m/μ\sim 0.4$. In the N=3 model an asymmetry in fermion masses $(m_1 < m_2 \ll m_3)$ removes the singularity at $θ=π$ and T=0. The chiral condensates at $θ=0$ are insensitive to the asymmetry in fermion masses, but are significantly sensitive at $θ=π$. The resultant picture is similar to that obtained in QCD by the chiral Lagrangian method.

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Yutaka Hosotani, Ramon Rodriguez. 1998-04-30. Bosonized Massive N-flavor Schwinger Model. https://doi.org/10.1088/0305-4470%2F31%2F49%2F013

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