We investigate the impact of a nonstandard time evolution of the dark matter component on current cosmological bounds from cosmic microwave background (CMB) anisotropies. We found that a less than 0.1% variation in the effective dark matter equation of state w(dm) can drastically change current CMB bounds on the matter density, the Hubble parameter and the age of the Universe. A flat universe without dark energy could provide an excellent fit to current CMB data, providing that w(dm) similar to -10(-2).
Cosmological constraints on the matter equation of state / Calabrese, Erminia; Marina, Migliaccio; Pagano, Luca; Grazia De, Troia; Melchiorri, Alessandro; Paolo, Natoli. - In: PHYSICAL REVIEW D, PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY. - ISSN 1550-7998. - 80:6(2009), pp. 063539-063542. [10.1103/physrevd.80.063539]
Cosmological constraints on the matter equation of state
CALABRESE, ERMINIA;PAGANO, LUCA;MELCHIORRI, Alessandro;
2009
Abstract
We investigate the impact of a nonstandard time evolution of the dark matter component on current cosmological bounds from cosmic microwave background (CMB) anisotropies. We found that a less than 0.1% variation in the effective dark matter equation of state w(dm) can drastically change current CMB bounds on the matter density, the Hubble parameter and the age of the Universe. A flat universe without dark energy could provide an excellent fit to current CMB data, providing that w(dm) similar to -10(-2).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
