Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


Published online December 29, 2023

Copyright © The Korean Physical Society.

Quantum scales of galaxies from ultralight dark matter

Jae‑Weon Lee

J. Korean Phys. Soc. 83(12), 1013 - 1018 (2023)


We propose that the ultralight dark matter (ULDM) model has characteristic scales for physical quantities of observed galaxies such as mass, size, acceleration, mass flux, and angular momentum from quantum mechanics. The typical angular momentum per dark matter particle is ℏ and the typical physical quantities are functions of specific angular momentum ℏ/m and average background density of the particles. If we use the Compton wavelength instead for the length scale, we can obtain bounds for these physical quantities. We suggest that the physical scales of galaxies depend on the time of their formation and that these characteristic scales are related to some mysteries of observed galaxies.