Nonlinear evolution of spherical perturbation in the Universe with cosmological constant and quintessence
نویسندگان
چکیده
We generalize the spherical collapse model for the formation of bound objects to apply in a Universe with cosmological constant and quintessence. We calculate the critical condition for collapse of an overdense region and give exact values of the characteristic densities and redshifts of its evolution. We apply the results to calculate the mass function of bound objects. Comparison with the data for clusters indicates a preference of models with quintessence over those with cosmological constant.
منابع مشابه
Nonlinear evolution of spherical perturbation in a non-flat Universe with cosmological constant
We generalize the spherical collapse model for the formation of bound objects to apply in a Universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact values of the characteristic densities and redshifts of its evolution.
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