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arXiv · hep-th/0401041

Integrable Open Spin Chains in Defect Conformal Field Theory

Oliver DeWolfe·Nelia Mann
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Abstract

We demonstrate that the one-loop dilatation generator for the scalar sector of a certain perturbation of N=4 Super Yang-Mills with fundamentals is the Hamiltonian of an integrable spin chain with open boundary conditions. The theory is a supersymmetric defect conformal field theory (dCFT) with the fundamentals in hypermultiplets confined to a codimension one defect. We obtain a K-matrix satisfying a suitably generalized form of the boundary Yang-Baxter equation, study the Bethe ansatz equations and demonstrate how Dirichlet and Neumann boundary conditions arise in field theory, and match to existing results in the plane wave limit.

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Oliver DeWolfe, Nelia Mann. 2004-03-31. Integrable Open Spin Chains in Defect Conformal Field Theory. https://doi.org/10.1088/1126-6708%2F2004%2F04%2F035

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