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arXiv · hep-th/9804047

The (1+1)-dimensional Massive sine-Gordon Field Theory and the Gaussian Wave-functional Approach

Wen-Fa Lu
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Abstract

The ground, one- and two-particle states of the (1+1)-dimensional massive sine-Gordon field theory are investigated within the framework of the Gaussian wave-functional approach. We demonstrate that for a certain region of the model-parameter space, the vacuum of the field system is asymmetrical. Furthermore, it is shown that two-particle bound state can exist upon the asymmetric vacuum for a part of the aforementioned region. Besides, for the bosonic equivalent to the massive Schwinger model, the masses of the one boson and two-boson bound states agree with the recent second-order results of a fermion-mass perturbation calculation when the fermion mass is small.

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Wen-Fa Lu. 1998-11-08. The (1+1)-dimensional Massive sine-Gordon Field Theory and the Gaussian Wave-functional Approach. https://doi.org/10.1103/physrevd.59.105021

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