riassunto2

Speaker	Lima, J. Ademir
Co-autors	*F. E. Silva, R. C. Santos*
Talk Title	Relativistic Accelerating Cosmology Driven by Cold Dark Matter
Abstract	A new accelerating flat model with no dark energy that is fully dominated by cold dark matter (CDM) is proposed. The number of CDM particles is not conserved and the present accelerating stage is a consequence of the negative pressure describing the irreversible process of gravitational particle creation. In this model, the present Hubble parameter does not need to be small in order to solve the age problem and the transition happens even if the matter creation is negligible during the radiation and part of the matter-dominated phase. Therefore, instead of the vacuum dominance at redshifts of the order of a few, the present accelerating stage in this sort of Einstein–de Sitter CDM cosmology is a consequence of the gravitational particle creation process. As an extra bonus, in the present scenario the coincidence problem does not exist which plagues models with dominance of dark energy. The model is able to harmonize a CDM picture with the present age of the universe, the latest measurements of the Hubble parameter and the supernovae observations.
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