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arXiv · 0801.3090

Dynamical vacuum energy via adjustment mechanism

A. D. Dolgov·F. R. Urban
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Abstract

A new mechanism of adjustment of vacuum energy down to the observed value from an initially huge one is considered. The mechanism is based on a very strong variation of the gravitational coupling constant in very early universe. The model predicts that the non--compensated remnant of vacuum energy changes very slowly at late stages of the cosmological evolution and is naturally close to the observed one. Asymptotically the effective vacuum energy tends to a negative value, so the cosmological expansion should stop and turn into contraction. There remains the problem of introduction of the usual matter into the model and therefore realising realistic cosmology.

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A. D. Dolgov, F. R. Urban. 2008-04-07. Dynamical vacuum energy via adjustment mechanism. https://doi.org/10.1103/physrevd.77.083503

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