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Astronomy

Decaying Dark Matter and the Core-Cusp Problem

Quick fact

Observations of dwarf galaxies show that their dark matter is smoothly distributed in the center (a 'core'), but computer simulations of cold dark matter predict a steeply rising 'cusp' — a decades-old contradiction that decaying dark matter might resolve.

Why this is interesting

Imagine a mountain of invisible matter that makes galaxies spin too fast – and then imagine that this mountain slowly melts, reshaping the galaxy's heart. Could that be why the centers of some galaxies are flat instead of pointed?