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Is the energy density of the ground state of the sine-Gordon model unbounded from below for beta^2 > 8 pi ?

M. Faber·A. N. Ivanov
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Abstract

We discuss Coleman's theorem concerning the energy density of the ground state of the sine-Gordon model proved in Phys. Rev. D 11, 2088 (1975). According to this theorem the energy density of the ground state of the sine-Gordon model should be unbounded from below for coupling constants beta^2 > 8 pi. The consequence of this theorem would be the non-existence of the quantum ground state of the sine-Gordon model for beta^2 > 8 pi. We show that the energy density of the ground state in the sine-Gordon model is bounded from below even for beta^2 > 8 pi. This result is discussed in relation to Coleman's theorem (Comm. Math. Phys. 31, 259 (1973)), particle mass spectra and soliton-soliton scattering in the sine-Gordon model.

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M. Faber, A. N. Ivanov. 2003-06-02. Is the energy density of the ground state of the sine-Gordon model unbounded from below for beta^2 > 8 pi ?. https://doi.org/10.1088/0305-4470%2F36%2F28%2F312

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