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Multiplicity of ground states in quantum field models: applications of asymptotic fields

Fumio Hiroshima
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Abstract

The ground states of an abstract model in quantum field theory are investigated. By means of the asymptotic field theory, we give a necessary and sufficient condition for that the expectation value of the number operator of ground states is finite, from which we obtain a wide-usable method to estimate an upper bound of the multiplicity of ground states. Ground states of massless GSB models and the Pauli-Fierz model with spin 1/2 are investigated as examples.

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Fumio Hiroshima. 2004-02-27. Multiplicity of ground states in quantum field models: applications of asymptotic fields. https://arxiv.org/abs/math-ph/0402075

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