Quantum Corrections to Gravity and Their Implications for Cosmology and Astrophysics

Abstract

The quantum contributions to the gravitational action are relatively easy to calculate in the higher derivative sector of the theory. However, the applications to the postinflationary cosmology and astrophysics require the corrections to the Einstein-Hilbert action and to the cosmological constant, and those we can not derive yet in a consistent and safe way. At the same time, if we assume that these quantum terms are covariant and that they have relevant magnitude, their functional form can be defined up to a single free parameter, which can be defined on the phenomenological basis. It turns out that the quantum correction may lead, in principle, to surprisingly strong and interesting effects in astrophysics and cosmology a .

Scalar-Tensor gravity with system-dependent potential and its relation with Renormalization Group extended General Relativity

“…where Φ N is the Newtonian potential, defined by ∇ 2 Φ N = 4πG 0 ρ (where ρ is a matter density profile) with Φ(r → ∞) = 0, Φ 0 is some constant and µ is the RG scale written in dimensionless form. Such setting has achieved interesting phenomenological achievements, and we speculated on its possible connection to dark matter [44,54,63,[70][71][72][73]. In order to both evaluate such proposal in other contexts, and to compare it to ST gravity, it is necessary to express the relation (2.16) in a covariant way.…”

Elliptical galaxies kinematics within general relativity with renormalization group effects

“…The main purpose of this work is to extend the analysis of [1] (see also [32,36,37], [38]) towards elliptical galaxies, testing the RGGR approach in this context. This extension is also of value to future RGGR applications, for instance in cluster of galaxies.…”

Vacuum stress tensor in spontaneous symmetry breaking theories

“…Some observational consequences of the possible quantum corrections were explored in [8,9] and led to establishing an upper bound on the magnitude of ν. Furthermore, the same unique form of quantum corrections was applied also to astrophysics [5] and was shown [10] to provide an accurate description of the rotation curves for some sample set of disk galaxies, without introducing a large amount of Dark Matter content (see [11] for more examples). Some other applications to cosmology and astrophysics were also discussed in Ref.…”