Non Collapse
The phenomenon of non-collapse describes the inability of dark matter to form compact astrophysical objects such as stars, planets, or black holes through standard gravitational contraction. Unlike baryonic matter, which consists of atoms and molecules, dark matter particles do not interact via the electromagnetic force. This fundamental difference in interaction mechanisms prevents dark matter from dissipating energy during gravitational collapse, thereby inhibiting the formation of dense, localized structures.
Ordinary matter undergoes gravitational collapse because it can radiate away kinetic energy through electromagnetic interactions, allowing it to cool and condense into high-density states. Dark matter, lacking these radiative cooling channels, retains its kinetic energy. As a result, it cannot settle into stable, compact configurations and instead remains distributed in diffuse halos or forms large-scale structures governed by collisionless dynamics.
Consequently, dark matter does not collapse into black holes via the same pathways as baryonic matter. While it contributes significantly to the gravitational potential wells that facilitate the collapse of ordinary matter, the dark matter itself remains non-collapsed on astrophysical scales. This distinction is critical for understanding the formation history of galaxies and the distribution of mass within the universe.