The structure and evolution of cold dark matter halos

TL;DR

This review discusses the structure, formation, and properties of cold dark matter halos within the standard cosmological model, highlighting robust simulation results, observational consistency, and ongoing challenges in understanding galaxy formation and dark matter detection.

Contribution

It provides a comprehensive overview of the current understanding of CDM halo properties, simulation accuracy, and the implications for dark matter detection and galaxy formation theories.

Findings

Halo mass profiles are consistent with observations across scales.

Simulations accurately reproduce halo substructure.

Discrepancies in galaxy formation predictions remain unresolved.

Abstract

In the standard cosmological model a mysterious cold dark matter (CDM) component dominates the formation of structures. Numerical studies of the formation of CDM halos have produced several robust results that allow unique tests of the hierarchical clustering paradigm. Universal properties of halos, including their mass profiles and substructure properties are roughly consistent with observational data from the scales of dwarf galaxies to galaxy clusters. Resolving the fine grained structure of halos has enabled us to make predictions for ongoing and planned direct and indirect dark matter detection experiments. While simulations of pure CDM halos are now very accurate and in good agreement (recently claimed discrepancies are addressed in detail in this review), we are still unable to make robust, quantitative predictions about galaxy formation and about how the dark matter distribution changes in the process. Whilst discrepancies between observations and simulations have been the subject of much debate in the literature, galaxy formation and evolution needs to be understood in more detail in order to fully test the CDM paradigm. Whatever the true nature of the dark matter particle is, its clustering properties must not be too different from a cold neutralino like particle to maintain all the successes of the model in matching large scale structure data and the global properties of halos which are mostly in good agreement with observations.