Towards a resolution of the cosmological singularity in non-local higher derivative theories of gravity

By Tirthabir Biswas, Tomi Koivisto, Anupam Mazumdar. 2010

255 citations recorded by the source corpus.

One of the greatest problems of standard cosmology is the Big Bang singularity. Previously it has been shown that non-local ghostfree higher-derivative modifications of Einstein gravity in the ultra-violet regime can admit non-singular bouncing solutions. In this paper we study in more details the dynamical properties of the equations of motion for these theories of gravity in presence of positive and negative cosmological constants and radiation. We find stable inflationary attractor solutions in the presence of a positive cosmological constant which renders inflation geodesically complete, while in the presence of a negative cosmological constant a cyclic universe emerges. We also provide an algorithm for tracking the super-Hubble perturbations during the bounce and show that the bouncing solutions are free from any perturbative instability.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/fd2860da8bbc04ef61382b1c68160ee1b53d250e

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Nuclear and High Energy Physics

Citations in the corpus

Generalized ghost-free quadratic curvature gravity (2013, background): “ing such terms can lead to interesting phenomenological consequences: since such modications are expected to produce bounce with a solution a(t) = a 0 cosh(t), where a 0 and are positive constants [6,8,11], which inevitably entail a super-in ationary phase near the bounce, such pre-in ationary dynam”
Occurrence of exact R2 inflation in non-local UV-complete gravity (2016, unknown): “For non-local models this aspect was discussed in details in [25, 66].”
Modified Gravity and Cosmology (2011, background): “Their consequences for inflation have been studied in [143, 551, 144, 42, 871, 977, 163], and the attractor nature of de Sitter space established.”
Notes on nonsingular models of black holes (2016, unknown): “[18] Tirthabir Biswas, Tomi Koivisto, and Anupam Mazumdar, “Towards a resolution of the cosmological singularity in non-local higher derivative theories of gravity,” JCAP 1011, 008 (2010), arXiv:1005.”
Towards understanding the ultraviolet behavior of quantum loops in infinite-derivative theories of gravity (2014, background): “For instance, in [2 0] a non-singular bouncing cosmological background was obtained within a class of infinite-deriv ative gravity theories, around which the sub and super-Hubble perturbations are well behaved and do n ot show instabilities [21, 22, 23].”
Stable bounce and inflation in non-local higher derivative cosmology (2012, methodology): “It has been demonstrated that such a modification of Einstein’s gravity ameliorates the UV behaviour of the Newtonian potential, and also permits symmetric non-singular oscillating solutions around the Minkowski space-time [14] signalling that the action can resolve the cosmological singularities, s”