Dark Matter Gravitational Clustering With a Long-Range Scalar Interaction

TL;DR

This paper investigates how a long-range scalar interaction among dark matter particles can enhance the standard b1CDM model at small scales, using N-body simulations to analyze clustering and halo properties.

Contribution

It introduces a scalar interaction to dark matter that improves small-scale clustering predictions without disrupting large-scale b1CDM results.

Findings

Scalar interactions increase dark matter clustering at megaparsec scales.

The modified model preserves b1CDM successes at larger scales.

Results show promising improvements in small-scale structure formation.

Abstract

We explore the possibility of improving the $\Lambda$CDM model at megaparsec scales by introducing a scalar interaction which increases the mutual gravitational attraction of dark matter particles. Using N-body simulations, we study the spatial distribution of dark matter particles and halos. We measure the effect of modifications in the Newton's gravity on properties of the two-point correlation function, the dark matter power spectrum, the cumulative halo mass function and density probability distribution functions. The results look promising: the scalar interactions produce desirable features at megaparsec scales without spoiling the $\Lambda$CDM successes at larger scales.