Modified Friedmann Cosmologies - theory & observations

Abstract

We investigate a class of Cardassian scenarios of the universe evolution in notions of the qualitative theory of dynamical systems. This theory allows us to analyze all solutions for all possible initial conditions on the phase plane. In the Cardassian models we find that big-rip singularities are present as a typical behavior in the future if $n<0$. Some exact solutions for the flat Cardassian models as well as a duality relation were found. In turn from the statistical analysis of Knop's SNIa data, without any priors on matter content in the model, we obtain that at the 99% confidence level this big-rip scenario will reach. The potential function for the Hamiltonian description of dynamics is reconstructed from the SNIa data (inverse dynamical problem). We also pointed out the statistical analysis results depend oversensitively on the choice of the model parameter $\mathcal{M}$.

RevTeX4, 30 pages, 11 figures

References in corpus (7)

• New Constraints on ${\Omega }_M$, ${\Omega }_{\Lambda }$, and w from an Independent Set of Eleven High-Redshift Supernovae Observed with HST
• Cosmological parameters from supernova observations: A critical comparison of three data sets
• Observational constraints on cosmology from modified Friedmann equation
• Constraints on Cardassian Scenario from the Expansion Turnaround Redshift and the Sunyaev-Zeldovich/X-ray Data
• Toward reconstruction of dynamics of the Universe from distant supernovae type Ia
• Probing the Evolution of the Dark Energy Density with Future Supernova Surveys
• Squeezing MOND into a Cosmological Scenario

Cited by in corpus (5)

• Dynamics of dark energy
• Cosmological zoo -- accelerating models with dark energy
• Classification of the FRW universe with a cosmological constant and a perfect fluid of the equation of state $p=w\rho$
• Large-scale structure and the Cardassian fluid
• Dark Energy, Hyperbolic Cosecant Cardassian and Virial Collapse for Power-style Cardassian