Cosmic vacuum energy decay and creation of cosmic matter

TL;DR

This paper reviews the role of cosmic vacuum energy and the cosmological constant in universe evolution, highlighting issues with the concept of a constant vacuum energy density and its implications for cosmology.

Contribution

It critically examines the concept of constant vacuum energy density and explores alternative ideas of vacuum energy decay and matter creation in cosmology.

Findings

Cosmic vacuum energy influences universe acceleration.

Constant vacuum energy density faces fundamental conceptual issues.

Alternative models involve vacuum decay and matter creation.

Abstract

In the more recent literature on cosmological evolutions of the universe the cosmic vacuum energy has become a non-renouncable ingredient. The cosmological constant $\Lambda$, first invented by Einstein, but later also rejected by him, presently experiences an astonishing revival. Interestingly enough it acts, like a constant vacuum energy density would also do. Namely, it has an accelerating action on cosmic dynamics without which, as it appears, presently obtained cosmological data cannot be conciliated with theory. As we are going to show in this review, however, the concept of a constant vacuum energy density is unsatisfactory for very basic reasons, since it would claim for a physical reality that acts upon spacetime and matter dynamics without itself being acted upon by spacetime or matter.