New Test Upends Assumption That Particle Dark Matter Is More Natural Than Black Holes

Physicist Stefano Profumo of UC Santa Cruz applied the same Barbieri-Giudice fine-tuning measure to 12 dark matter scenarios. Both particle models and primordial black holes span the range from natural to highly tuned. The results appear in Physical Review D.

• 12 dark matter scenarios compared, including WIMP, Higgs-resonance annihilation and primordial black hole formation mechanisms
• A domain-wall collapse black hole scenario ranked among the most natural models in the analysis
• The Higgs-resonance particle model requires a parameter tuned to within a fraction of a percent
• Naturalness depends on the production mechanism, not on whether dark matter is particles or black holes