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arXiv · 2204.02190

Healing the cosmological constant problem during inflation through a unified quasi-quintessence matter field

Rocco D'Agostino·Orlando Luongo·Marco Muccino
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Abstract

We heal the cosmological constant problem by means of a \emph{cancellation mechanism} that adopts a phase transition during which quantum fluctuations are eliminated. To this purpose, we propose that a generalized scalar (dark) matter field with a non-vanishing pressure term can remove the vacuum energy contribution, if its corresponding thermodynamics is written in terms of a \emph{quasi-quintessence} representation. In such a picture, pressure differs from quintessence as it shows a zero kinetic contribution. Using this field, we investigate a metastable transition phase, in which the universe naturally passes through an inflationary phase. To reach this target, we single out a double exponential potential, describing the metastable inflationary dynamics by considering suitable boundaries and thermodynamic conditions. We analyze stability investigating saddle, stable and unstable points and we thus predict a chaotic inflation that mimics the Starobinsky exponential potential. Consequently, the role of the proposed dark matter field is investigated throughout the overall universe evolution. To do so, we provide a physical explanation on unifying the dark sector with inflation by healing the cosmological constant problem.

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Rocco D'Agostino, Orlando Luongo, Marco Muccino. 2022-04-05. Healing the cosmological constant problem during inflation through a unified quasi-quintessence matter field. https://doi.org/10.1088/1361-6382%2Fac8af2

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