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Manifestation of a nontrivial vacuum in discrete light cone quantization

Takanori Sugihara·Masa-aki Taniguchi
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Abstract

We study a (1+1)-dimensional $λϕ^4$ model with a light-cone zero mode and constant external source to describe spontaneous symmetry breaking. In the broken phase, we find degenerate vacua and discuss their stability based on effective-potential analysis. The vacuum triviality is spurious in the broken phase because these states have lower energy than Fock vacuum. Our results are based on the variational principle.

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Takanori Sugihara, Masa-aki Taniguchi. 2001-11-09. Manifestation of a nontrivial vacuum in discrete light cone quantization. https://doi.org/10.1103/physrevlett.87.271601

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