Possible Duplicate:
Why do neutrons repel each other?
What I mean is that the neutrons are attracted to one another via gravity, so what force keeps them from collapsing to form a "neutron black hole"? Considering that they have no electric charge...
It's well explained at wikipedia:
Neutron stars are very hot and are supported against further collapse by quantum degeneracy pressure due to the Pauli exclusion principle. This principle states that no two neutrons (or any other fermionic particles) can occupy the same place and quantum state simultaneously.
