Black Holes May Carry Fermionic Hair, Defying Zero Tidal Response
New research using fermionic (Dirac) fields on rotating Kerr black holes suggests the traditional zero tidal Love number for black holes can be violated by fermionic perturbations, hinting at a possible fermionic hair and expanding how we probe black-hole structure—without overturning general relativity, but adding a new layer to black-hole phenomenology.