Effective cosmological constant induced by stochastic fluctuations of Newton's constant

We consider implications of the microscopic dynamics of spacetime for the evolution of cosmological models. We argue that quantum geometry effects may lead to stochastic fluctuations of the gravitational constant, which is thus considered as a macroscopic effective dynamical quantity. Consistency wi...

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Bibliographic Details
Main Authors: Marco de Cesare, Fedele Lizzi, Mairi Sakellariadou
Format: Article
Language:English
Published: Elsevier 2016-09-01
Series:Physics Letters B
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0370269316303562
Description
Summary:We consider implications of the microscopic dynamics of spacetime for the evolution of cosmological models. We argue that quantum geometry effects may lead to stochastic fluctuations of the gravitational constant, which is thus considered as a macroscopic effective dynamical quantity. Consistency with Riemannian geometry entails the presence of a time-dependent dark energy term in the modified field equations, which can be expressed in terms of the dynamical gravitational constant. We suggest that the late-time accelerated expansion of the Universe may be ascribed to quantum fluctuations in the geometry of spacetime rather than the vacuum energy from the matter sector.
ISSN:0370-2693
1873-2445