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arXiv · 1012.4848

Cosmological constant in scale-invariant theories

Robert Foot·Archil Kobakhidze·Raymond R. Volkas
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Abstract

The incorporation of a small cosmological constant within radiatively-broken scale-invariant models is discussed. We show that phenomenologically consistent scale-invariant models can be constructed which allow a small positive cosmological constant, providing certain relation between the particle masses is satisfied. As a result, the mass of the dilaton is generated at two-loop level. Another interesting consequence is that the electroweak symmetry-breaking vacuum in such models is necessarily a metastable `false' vacuum which, fortunately, is not expected to decay on cosmological time scales.

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Robert Foot, Archil Kobakhidze, Raymond R. Volkas. 2010-12-22. Cosmological constant in scale-invariant theories. https://doi.org/10.1103/physrevd.84.075010

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