Tiny black holes could make up all dark matter. New research shows that they were born from the magnetic fields of the young Universe, twisted into giant vortices. Unlike black holes from dying stars, these were born from pure magnetic field energy when the Universe was less than a second old. The vortices swept matter into clumps that collapsed under their own weight, like a snowball compressed to the size of a grain of sand.

Calculations showed: if the temperature of the early Universe lay in a narrow range, like a hot but not scorching skillet, then the number of born black holes exactly accounts for all dark matter. Detecting the waves would be direct proof. Stephen Hawking pondered such objects, but now we have a clear plan to find them. This opens a new path to understanding both dark matter and the first moments after the Big Bang.