Scalar Field (Wave) Dark Matter

TL;DR

This paper discusses scalar field dark matter as an alternative to cold dark matter, highlighting its ability to produce flat galaxy core profiles and address small-scale structure issues, with future telescopes poised to test this model.

Contribution

It reviews the scalar field dark matter model's potential to resolve core-cusp problems and small-scale structure discrepancies in galaxy observations.

Findings

Scalar field dark matter can produce flat density profiles in dwarf galaxies.

It reduces the number of small halos compared to standard CDM.

The model aligns with galaxy rotation curves and early galaxy formation evidence.

Abstract

Recent high-quality observations of dwarf and low surface brightness (LSB) galaxies have shown that their dark matter (DM) halos prefer flat central density profiles. On the other hand the standard cold dark matter model simulations predict a more cuspy behavior. Feedback from star formation has been widely used to reconcile simulations with observations, this might be successful in field dwarf galaxies but its success in low mass galaxies remains uncertain. One model that have received much attention is the scalar field dark matter model. Here the dark matter is a self-interacting ultra light scalar field that forms a cosmological Bose-Einstein condensate, a mass of $10^{-22}$eV/c$^2$ is consistent with flat density profiles in the centers of dwarf spheroidal galaxies, reduces the abundance of small halos, might account for the rotation curves even to large radii in spiral galaxies and has an early galaxy formation. The next generation of telescopes will provide better constraints to the model that will help to distinguish this particular alternative to the standard model of cosmology shedding light into the nature of the mysterious dark matter.