The cosmological constant and entropy problems: mysteries of the present with profound roots in the past

Abstract

An accelerated universe should naturally have a vacuum energy density determined by its dynamical curvature. The cosmological constant is most likely a temporary description of a dynamical variable that has been drastically evolving from the early inflationary era to the present. In this Essay we propose a unified picture of the cosmic history implementing such an idea, in which the cosmological constant problem is fixed at early times. All the main stages, from inflation and its ("graceful") exit into a standard radiation regime, as well as the matter and dark energy epochs, are accounted for. Finally, we show that for a generic Grand Unified Theory associated to the inflationary phase, the amount of entropy generated from primeval vacuum decay can explain the huge measured value today.

This essay received an Honorable Mention from the Gravity Research Foundation (2015) Awards Essays on Gravitation. Updated references, version published in Int. J. of Mod. Phys. D

References in corpus (9)

• Searching for dark matter and variation of fundamental constants with laser and maser interferometry
• Dark energy: a quantum fossil from the inflationary Universe?
• Dynamical vacuum energy in the expanding Universe confronted with observations: a dedicated study
• The $\bar{\Lambda }CDM$ cosmology: from inflation to dark energy through running $\Lambda$
• Vacuum models with a linear and a quadratic term in H: structure formation and number counts analysis
• Nonsingular Decaying Vacuum Cosmology and Entropy Production
• Fundamental constants and cosmic vacuum: the micro and macro connection
• Fundamental Constants in Physics and Their Time Variation
• Dark matter, dark energy and the time evolution of masses in the Universe

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