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Exact C=1 Boundary Conformal Field Theories

Curtis G. Callan·Igor R. Klebanov
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Abstract

We present a solution of the problem of a free massless scalar field on the half line interacting through a periodic potential on the boundary. For a critical value of the period, this system is a conformal field theory with a non-trivial and explicitly calculable S-matrix for scattering from the boundary. Unlike all other exactly solvable conformal field theories, it is non-rational ({\it i.e.} has infinitely many primary fields). It describes the critical behavior of a number of condensed matter systems, including dissipative quantum mechanics and of barriers in ``quantum wires''.

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Curtis G. Callan, Igor R. Klebanov. 1993-11-17. Exact C=1 Boundary Conformal Field Theories. https://doi.org/10.1103/physrevlett.72.1968

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