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arXiv · hep-th/9909145

Boundary breathers in the sinh-Gordon model

E. Corrigan·G. W. Delius
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Abstract

We present an investigation of the boundary breather states of the sinh-Gordon model restricted to a half-line. The classical boundary breathers are presented for a two parameter family of integrable boundary conditions. Restricting to the case of boundary conditions which preserve the ϕ--> -ϕsymmetry of the bulk theory, the energy spectrum of the boundary states is computed in two ways: firstly, by using the bootstrap technique and subsequently, by using a WKB approximation. Requiring that the two descriptions of the spectrum agree with each other allows a determination of the relationship between the boundary parameter, the bulk coupling constant, and the parameter appearing in the reflection factor derived by Ghoshal to describe the scattering of the sinh-Gordon particle from the boundary.

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E. Corrigan, G. W. Delius. 1999-09-21. Boundary breathers in the sinh-Gordon model. https://doi.org/10.1088/0305-4470%2F32%2F49%2F303

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