3rd Italian-Sino Italian Participants |
|
|
Page 6 of 6
G.V. Vereshchagin
*University of Rome "La Sapienza"
*I.C.R.A.- International Center for Relativistic
Astrophysics
Title:
Hidden invariance in Gurzadyan朮ue cosmological models
Authors: G.V. Vereshchagin, G. Yegorian
Abstract: The dark energy formula derived by Gurzadyan and Xue
which leads to a value fitting the SN data, provides a
scaling relation between physical constants and cosmological parameters and
defines a set of cosmological models. In previous works we considered several
of those models and derived cosmological equations for each of them. In this
Letter we present the phase portrait analysis of those models. Surprisingly, we
found that the separatrix in the phase space which
determines the character of solutions depends solely on the value of the
current matter density, namely: at Om > 2/3 the
equations describe Friedmannian Universe with the classical
singularity at the beginning, while at Om < 2/3
all solutions for the considered models start with zero density and
non-vanishing scale factor. Even more remarkable, the value Osep
= 2/3, which defines the separatrix, is the same for
all models. The latter reveals an underlying invariance hidden in the models,
possibly, due to the basic nature of the GX-scaling.
|