Advances in Astronomy and Space Physics, Volume 7, Issue 1-2, PP. 17-22 (2017)
doi: 10.17721/2227-1481.7.17-22

Qualitative types of cosmological evolution in
hydrodynamic models with barotropic equation of state

S. S. Dylda, V. I. Zhdanov

Astronomical Observatory, Taras Shevchenko National University of Kyiv, Observatorna str., 3, Kyiv, 04053, Ukraine

We study solutions of the Friedmann equations in case of the homogeneous isotropic Universe filled with a perfect fluid. The main points concern the monotony properties of the solutions, the possibility to extend the solutions on all times and occurrence of singularities. We present a qualitative classification of all possible solutions in case of the general smooth barotropic equation of state of the fluid, provided the speed of sound is finite. The list of possible scenarios includes analogues of the "Big Rip" in the future and/or in the past as well as singularity free solutions and oscillating Universes. Extensions of the results to the multicomponent fluids are discussed.

cosmology: theory, early Universe, dark energy