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Excited-state thermodynamics

Paul Fendley
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Abstract

In the last several years, the Casimir energy for a variety of 1+1-dimensional integrable models has been determined from the exact S-matrix. It is shown here how to modify the boundary conditions to project out the lowest-energy state, which enables one to find excited-state energies. This is done by calculating thermodynamic expectation values of operators which generate discrete symmetries. This is demonstrated with a number of perturbed conformal field theories, including the Ising model, the three-state Potts model, ${\bf Z}_n$ parafermions, Toda minimal S-matrices, and massless Goldstinos.

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Paul Fendley. 1991-09-11. Excited-state thermodynamics. https://doi.org/10.1016/0550-3213(92)90404-y

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