Barotropic FRW cosmologies with Chiellini damping in comoving time
Abstract
For nonzero cosmological constant Λ, we show that the barotropic FRW cosmologies as worked out in the comoving time lead in the radiationdominated case to scale factors of identical form as for the Chiellini dissipative scale factors in conformal time obtained recently by us in Phys. Lett. A 379, 882 (2015). This is due to the Ermakov equation which is obtained in this case. For zero cosmological constant, several textbook solutions are easily obtained as particular cases of our formulas and hypergeometric solutions are also reminded.
 Publication:

Modern Physics Letters A
 Pub Date:
 May 2015
 DOI:
 10.1142/S021773231550100x
 arXiv:
 arXiv:1502.07033
 Bibcode:
 2015MPLA...3050100R
 Keywords:

 Barotropic fluid;
 FRW cosmology;
 cosmological constant;
 04.20.Cv;
 Fundamental problems and general formalism;
 Mathematical Physics
 EPrint:
 4 pages, version accepted at MPLA