New Lower Bound on Ultralight Bosonic Dark Matter Mass

A new study in Physical Review Letters establishes a new lower bound on the mass of ultralight bosonic dark matter particles. By analyzing stellar kinematics in the Leo II dwarf galaxy, researchers reconstructed the dark matter wave function density. They found that dark matter particles lighter than 2.2 × 10⁻²¹ electron volts cannot reproduce the observed dark matter density distribution. This significantly improves the lower bound on dark matter mass and challenges popular fuzzy dark matter models.