Scale Dependence of Nonlinear Gravitational Clustering in the Universe
نویسندگان
چکیده
We extend the thermodynamic theory of gravitational clustering in an expanding Universe to include the scale dependence of the ratio, b, of gravitational correlation energy to thermal energy. The predicted form of the gravitational quasi-equilibrium distribution function is unchanged by this scale dependence. This generalization of the theory contains no free parameters, and clariies many earlier results. It explains the improved agreement found previously between simulations, observations, and theory when b is allowed to depend on scale. Our new results are connrmed by comparisons with N-body simulations which now agree to an accuracy of about 98%.
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