Dark Matter May Have Started ‘Hot’ in Early Universe, New research Suggests
A new study challenges cosmological assumptions, suggesting dark matter-about 85% of the universe’s mass-may have initially been “hot,” or high-speed, shortly after the Big Bang.
Dark Matter’s State-For decades, “cold dark matter,” moving slowly, was considered essential for galaxy formation. This research proposes dark matter could have separated from early plasma at near-light speed.
Key Findings-Published in Physical Review Letters (February 2025), the study focuses on “reheating” after the universe’s rapid expansion (“inflation”). Dark matter created then could have cooled sufficiently to form cosmic structures.
Neutrino Implications-The research revisits the neutrino, once a hot dark matter candidate ruled out for hindering structure formation. Similar particles created during reheating could cool and act as cold dark matter.
Future Research-The findings impact the search for dark matter via particle colliders, underground detectors, and astrophysical observations, potentially unlocking insights into the universe’s earliest moments.
