Evolution Of Gravitational Potential In The Quasilinear And Nonlinear Regimes

TL;DR

This paper investigates how the gravitational potential evolves during nonlinear clustering in matter-dominated universes, revealing that potential evolution varies with the spectral index and affects CDM-like models.

Contribution

It provides new insights into the evolution of gravitational potential in different regimes and spectral indices, highlighting a specific behavior in CDM-like models.

Findings

Potential remains constant in quasilinear phase for n=-1.

Potential evolves in quasilinear but not in nonlinear phase for n=-2.

Potential evolution in CDM spectra is less than naive expectations.

Abstract

We study the evolution of the power spectrum of gravitational potential during the nonlinear clustering in an $\Omega=1$ matter dominated phase. N-body simulations suggest that the potential does not evolve in time even in the quasilinear phase for an $n=-1$ power spectrum. For $n=-2$, the potential evolves in the quasilinear phase but not in the extreme nonlinear phase. Becauase of these facts, the evolution of the gravitational potential in spectra like CDM is less than what would have been expected naively. We discuss a class of CDM like models in which such an interesting conspiracy between the amplitude and local index occurs.