Research team proposes self-interacting dark matter theory for three cosmic anomalies
Updated
Updated · Space.com · May 6
Research team proposes self-interacting dark matter theory for three cosmic anomalies
8 articles · Updated · Space.com · May 6
The study links JVAS B1938+666, the GD-1 star-stream scar and Fornax 6 to dense dark matter cores formed by particle collisions, and was published on 9 April in Physical Review Letters.
Hai-Bo Yu of the University of California, Riverside said the same mechanism could work across the distant universe, the Milky Way and a nearby satellite galaxy.
The proposal challenges the standard lambda cold dark matter model, in which dark matter is slow-moving and effectively collisionless, making such dense structures harder to explain.
Could dark matter's self-interactions form entirely new objects, like invisible 'dark stars' or black holes?
Is dark matter a particle, or could it be a quantum fog that redefines gravity's effects?
Why would dark matter particles collide in small galaxies but act like ghosts in massive galaxy clusters?
Self-Interacting Dark Matter and Gravothermal Collapse Explain Lensing, Stellar Streams, and Star Cluster Compactness
Overview
In 2026, Hai-Bo Yu's team revealed that Self-Interacting Dark Matter (SIDM) particles collide through forces beyond gravity, triggering gravothermal collapse in dark matter halos. This process causes heat to flow outward, cooling and contracting the core to form ultra-dense clumps about a million times the mass of the sun. These dense clumps explain three cosmic puzzles: the strong gravitational lensing in JVAS B1938+666, the spur-and-gap features in the GD-1 stellar stream, and the compactness of the Fornax 6 star cluster, which survives due to a reduced number of small disruptive subhalos. This unified SIDM framework also addresses the core-cusp and missing satellites problems, with upcoming astronomical surveys and particle experiments poised to test its predictions.