Mathematics – Logic
Scientific paper
Feb 1999
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1999mnras.302..625a&link_type=abstract
Monthly Notices of the Royal Astronomical Society, Volume 302, Issue 4, pp. 625-631.
Mathematics
Logic
1
Scientific paper
We investigate the cosmology of x-matter with pressure, px, and density, ρx, related by px=w0ργx(w0<0γ >0). For γ >1, this x-matter behaves like a cosmological constant when a<< a0 (a being the scalefactor and a0 the scalefactor at present) and like matter for a γ a0; for γ <1, the behaviour is the opposite; for γ =1, the x-matter density varies as a-3(1+w0). Models of x-matter with γ >1 reach, at all times, densities lower than do models with γ <= 1 for equal present x-matter density, so the former have less effect on the formation of structures in the Universe. Allowed values for the free parameters of these cosmological models are estimated by imposing two observational constraints which originate from the age problem of the Universe and from the luminosity-distance relation for Type Ia supernovae at z=0.4.
Aguerri Jose-Alfonso L.
Membrado M.
No associations
LandOfFree
A general model of x-matter does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A general model of x-matter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A general model of x-matter will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-945604