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Field theory models for variable cosmological constant

Gia Dvali·Alexander Vilenkin
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Abstract

Anthropic solutions to the cosmological constant problem require seemingly unnatural scalar field potentials with a very small slope or domain walls (branes) with a very small coupling to a four-form field. Here we introduce a class of models in which the smallness of the corresponding parameters can be attributed to a spontaneously broken discrete symmetry. We also demonstrate the equivalence of scalar field and four-form models. Finally, we show how our models can be naturally embedded into a left-right extension of the standard model.

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Gia Dvali, Alexander Vilenkin. 2001-06-14. Field theory models for variable cosmological constant. https://doi.org/10.1103/physrevd.64.063509

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