Dark energy in modified GaussBonnet gravity: Latetime acceleration and the hierarchy problem
Abstract
Dark energy cosmology is considered in a modified GaussBonnet (GB) model of gravity where an arbitrary function of the GB invariant, f(G), is added to the general relativity action. We show that a theory of this kind is endowed with a quite rich cosmological structure: it may naturally lead to an effective cosmological constant, quintessence, or phantom cosmic acceleration, with a possibility for the transition from deceleration to acceleration. It is demonstrated in the paper that this theory is perfectly viable, since it is compliant with the solar system constraints. Specific properties of f(G) gravity in a de Sitter (dS) universe, such as dS and SdS solutions, their entropy, and its explicit oneloop quantization are studied. The issue of a possible solution of the hierarchy problem in modified gravities is also addressed.
 Publication:

Physical Review D
 Pub Date:
 April 2006
 DOI:
 10.1103/PhysRevD.73.084007
 arXiv:
 arXiv:hepth/0601008
 Bibcode:
 2006PhRvD..73h4007C
 Keywords:

 04.50.+h;
 95.36.+x;
 Gravity in more than four dimensions KaluzaKlein theory unified field theories;
 alternative theories of gravity;
 Dark energy;
 High Energy Physics  Theory;
 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology
 EPrint:
 LaTeX file 20 pages, new subsections are added