We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Stable exponential cosmological solutions with three different Hubble-like parameters in EGB model with a Λ-term.
- Authors
Ernazarov, K. K.; Ivashchuk, V. D.
- Abstract
We consider a D-dimensional Einstein-Gauss-Bonnet model with a cosmological term Λ and two non-zero constants: α 1 and α 2 . We restrict the metrics to be diagonal ones and study 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 , obeying m H + k 1 h 1 + k 2 h 2 ≠ 0 and corresponding to factor spaces of dimensions m > 1 , k 1 > 1 and k 2 > 1 , respectively ( D = 1 + m + k 1 + k 2 ). We analyse two cases: i) m < k 1 < k 2 and ii) 1 < k 1 = k 2 = k , k ≠ m . We show that in both cases the solutions exist if α = α 2 / α 1 > 0 and α Λ > 0 satisfies certain restrictions, e.g. upper and lower bounds. In case ii) explicit relations for exact solutions are found. In both cases the subclasses of stable and non-stable solutions are singled out. For m > 3 the case i) contains a subclass of solutions describing an exponential expansion of 3-dimensional subspace with Hubble parameter H > 0 and zero variation of the effective gravitational constant G. The case H = 0 is also considered.
- Subjects
HUBBLE Space Telescope (Spacecraft); HUBBLE constant; GRAVITATIONAL constant; PHYSICAL cosmology; PROTOSTARS
- Publication
European Physical Journal C -- Particles & Fields, 2020, Vol 80, Issue 6, p1
- ISSN
1434-6044
- Publication type
Article
- DOI
10.1140/epjc/s10052-020-8107-3