Stable exponential cosmological solutions with zero variation of G and three different Hubble-like parameters in the Einstein–Gauss–Bonnet model with a Λ-term

• Published in: The European physical journal. C, Particles and fields Vol. 77; no. 6; pp. 1 - 7
• Main Authors: Ernazarov, K. K., Ivashchuk, V. D.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2017; Springer Nature B.V
• Subjects: Astronomy; Astrophysics and Cosmology; Elementary Particles; Gravitation; Gravitational constant; Hadrons; Heavy Ions; Mathematical models; Measurement Science and Instrumentation; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Regular Article - Theoretical Physics; String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-017-4974-7

We consider a D -dimensional gravitational model with a Gauss–Bonnet term and the cosmological term Λ . We restrict the metrics to diagonal cosmological ones and find for certain Λ a class of solutions with exponential time dependence of three scale factors, governed by three non-coinciding Hubble-like parameters H > 0 , h 1 and h 2 , corresponding to factor spaces of dimensions m > 2 , k 1 > 1 and k 2 > 1 , respectively, with k 1 ≠ k 2 and D = 1 + m + k 1 + k 2 . Any of these solutions describes an exponential expansion of 3 d subspace with Hubble parameter H and zero variation of the effective gravitational constant G . We prove the stability of these solutions in a class of cosmological solutions with diagonal metrics.