2023/11/22 by Boris Zupancic, Zupancic, Boris, Lawrence M. Widrow +1
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #Statistical Mechanics and Entropy
paper · pdf · doi:10.48550/arxiv.2311.13352
openalex publication_date 2023/11/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Dark matter may be composed of ultra-light bosons whose de Broglie wavelength in galaxies is of order 1 kpc. The standard model for this fuzzy dark matter (FDM) is a complex scalar field that obeys the Schrödinger-Poisson equations. The wavelike nature of FDM leads to fluctuations in the gravitational field that can pump energy into the stellar components of a galaxy. Heuristic arguments and theoretical analyses suggest that these fluctuations can be modelled by replacing FDM with a system of quasiparticles (QPs). We test this hypothesis by comparing self-consistent simulations of a Schrödinger field with those using a system of QPs in one spatial dimension. Simulations of pure FDM systems allow us to derive a phenomenological relation between the number of QPs that is required to model FDM with a given de Broglie wavelength. We also simulate systems of FDM and stars and find that the FDM pumps energy into the stars whether it is described by QPs or a Schrödinger field with the FDM adiabatically contracting and the stellar system adiabatically expanding. However, we find that QPs overestimate dynamical heating.