Closed and open FRW cosmologies with matter creation: Kinematic tests

نویسنده

  • J. S. Alcaniz
چکیده

The limits imposed by the classical cosmological tests on closed and open FRW universes driven by adiabatic matter creation are investigated. Exact expressions for the lookback time, age of the universe, luminosity distance, angular diameter, and galaxy number counts versus redshift are derived and their meaning discussed in detail. An interesting consequence of these cosmological models is the possibility of an accelerated expansion today (as indicated from supernovae observations) with no need to invoke either a cosmological constant or an exotic “quintessence” component.

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تاریخ انتشار 1999