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arXiv · hep-th/0312168

Integrable Model of Boundary Interaction: The Paperclip

S. L. Lukyanov·E. S. Vitchev·A. B. Zamolodchikov
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Abstract

We consider a model of 2D quantum field theory on a disk, whose bulk dynamics is that of a two-component free massless Bose field (X,Y), and interaction occurs at the boundary, where the boundary values (X_B, Y_B) are constrained to special curve - the ``paperclip brane''. The interaction breaks conformal invariance, but we argue that it preserves integrability. We propose exact expression for the disk partition function (and more general overlap amplitudes < P | B > of the boundary state with all primary states) in terms of solutions of certain ordinary linear differential equations.

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S. L. Lukyanov, E. S. Vitchev, A. B. Zamolodchikov. 2003-12-15. Integrable Model of Boundary Interaction: The Paperclip. https://doi.org/10.1016/j.nuclphysb.2004.02.010

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