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arXiv · hep-th/9512193

Coherent and squeezed condensates in massless $λφ^4$ theory

H. -P. Pavel·D. Blaschke·G. Roepke·V. N. Pervushin
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Abstract

Generalizing the Bogoliubov model of a weakly non-ideal Bose gas to massless $λφ^4$ theory we show that spontaneous breaking of symmetry occurs due to condensation in a coherent vacuum % which is energetically favoured compared to the perturbative one. and leads to a vacuum energy density which is lower than that obtained by Coleman and Weinberg using the one-loop effective potential method. We discuss the alternative of a squeezed condensate and find that for the massless $λφ^4$ theory spontaneous symmetry breaking to a squeezed vacuum does not occur.

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H. -P. Pavel, D. Blaschke, G. Roepke, V. N. Pervushin. 1995-12-23. Coherent and squeezed condensates in massless $λφ^4$ theory. https://arxiv.org/abs/hep-th/9512193

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