Does electron degeneracy pressure act against gravity pressure in a white dwarf forever?

Question

What happens when the white dwarf eventually cools and dims, does gravity pressure take over again? or does electron degeneracy pressure somehow continue.

If it doesn't continue and the core starts to contract again what happens to the remnant? does it become a black hole?

Same question about neutron stars please and neutron degeneracy pressure.

Answer 1

electron degeneracy pressure has nothing to do with heat or molecular pressure pushing it apart. electron degeneracy pressure is the electromagnetic repulsion between electrons, which has nothing to do with heat.

neutron degeneracy pressure is slightly different. it still has nothing to do with heat though. it has to do with the uncertainty principle and the fact that 2 particles cant take up the same space.

Answer 2

Heat isn't that great a factor in white dwarfs. You need a certain amount of gravity to force the electrons into the protons and create a neutron star, and white dwarfs don't have enough mass to do the job. Same with a neutron star. They need more mass than they have to break the neutrons down to quarks, or create black holes. The temperature isn't really much of a factor.

Answer 3

Electron degeneracy pressure is an energy resulting from the Pauli exclusion principle. It does not permit two fermions (electrons are fermions) to have the same quantum state. This then places a limit on how much matter can be in a certain area -- at least until the pressure is insufficient.

The pressure itself does not care about temperature. As the white dwarf cools, the Pauli exclusion principle continues to hold -- it is a quantum mechanical result.

Electron degeneracy pressure works until the Chandrasekhar limit, about 1.4 solar masses. The white dwarf is not burning anything, but its gravity may still suck things in -- if its mass goes over that limit, it may collapse further.

Similarly with neutron degeneracy pressure. The Pauli exclusion principle does not permit two neutrons to occupy the same quantum state, and as a result, places a limit on the number of neutrons permissible in an area. Again though, if the mass is sufficient, the neutrons fall apart and the degeneracy pressure is defeated. At this point, it might become a theorized "quark star" which relies on 'quark degeneracy pressure' or a black hole.