  The majority of baryons, which account for $15\%$ of the matter in the
Universe, will end their lives as carbon and oxygen inside cold black dwarfs.
Dark matter (DM) makes up the remaining $85\%$ of the matter in the universe,
however, the fate of DM is unknown. Here we show that the destiny of purely
gravitationally interacting DM particles follows one of two possible routes.
The first possible route, the "radiation-destiny" scenario, is that massive DM
particles lose sufficient energy through gravitational radiation causing them
to spiral into a supermassive black hole that ultimately disappears through
Hawking radiation. The second possible route, the "drifting-alone" destiny,
applies to lighter DM particles, where only the central DM halo region spirals
into the central BH which is then Hawking radiated away. The rest of the DM
halo is ripped apart by the accelerated expansion of the Universe.
