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arXiv · hep-th/0108039

Integrable Boundary Conditions and Reflection Matrices for the O(N) Nonlinear Sigma Model

M. Moriconi
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Abstract

We find new integrable boundary conditions, depending on a free parameter $g$, for the O(N) nonlinear $σ$ model, which are of nondiagonal type, that is, particles can change their ``flavor'' through scattering off the boundary. These boundary conditions are derived from a microscopic boundary lagrangian, which is used to establish their integrability, and exhibit integrable flows between diagonal boundary conditions investigated earlier. We solve the boundary Yang-Baxter equation, connect these solutions to the boundary conditions, and examine the corresponding integrable flows.

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M. Moriconi. 2001-08-20. Integrable Boundary Conditions and Reflection Matrices for the O(N) Nonlinear Sigma Model. https://doi.org/10.1016/s0550-3213(01)00527-2

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