https://doi.org/10.1140/epjc/s10052-020-8107-3
Regular Article - Theoretical Physics
Stable exponential cosmological solutions with three different Hubble-like parameters in EGB model with a 
-term
1
Institute of Gravitation and Cosmology, Peoples’ Friendship University of Russia (RUDN University), 6 Miklukho-Maklaya Street, Moscow, 117198, Russian Federation
2
Center for Gravitation and Fundamental Metrology, VNIIMS, 46 Ozyornaya Street, Moscow, 119361, Russian Federation
* e-mail: ivashchuk@mail.ru
Received:
30
March
2020
Accepted:
2
June
2020
Published online:
16
June
2020
We consider a D-dimensional Einstein-Gauss-Bonnet model with a cosmological term and two non-zero constants: 
and 
. 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: 
, 
and 
, obeying 
and corresponding to factor spaces of dimensions 
, 
and 
, respectively (
). We analyse two cases: i) 
and ii) 
, 
. We show that in both cases the solutions exist if 
and 
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 
the case i) contains a subclass of solutions describing an exponential expansion of 3-dimensional subspace with Hubble parameter 
and zero variation of the effective gravitational constant G. The case 
is also considered.
© The Author(s), 2020
