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arXiv · 0905.1771

Recovering Unitarity of Lee Model in Bi-Orthogonal Basis

T. Shi·C. P. Sun
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Abstract

We study how to recover the unitarity of Lee model with the help of bi-orthogonal basis approach, when the physical coupling constant in renormalization exceeds its critical value, so that the Lee's Hamiltonian is non-Hermitian with respect to the conventional inner product. In a very natural fashion, our systematic approach based on bi-orthogonal basis leads to an elegant definition of inner product with a non-trivial metric, which can overcome all the previous problems in Lee model, such as non-Hermiticity of the Hamiltonian, the negative norm, the negative probability and the non-unitarity of the scattering matrix.

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T. Shi, C. P. Sun. 2009-05-29. Recovering Unitarity of Lee Model in Bi-Orthogonal Basis. https://arxiv.org/abs/0905.1771

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