Re: Matter/antimatter vs "regular"/"dark" matter
But when a star forms it is gravity that pulls it all together and the other forces that, via solar ignition/fusion, keep it from collapsing completely - so what keeps dark matter diffuse ?
The simple answer is "heat". The particles are speeding around and can't dump their kinetic energy (because they don't interact with anything). So they don't slow down and form large self-gravitating halos.