Electron degeneracy pressure

Electron degeneracy pressure is the resistance to compression produced when the Pauli exclusion principle forces electrons into increasingly energetic quantum states. It can support matter even when thermal pressure is negligible.

Pauli exclusion principle: No two identical fermions can occupy the same quantum state. It prevents electrons from all settling into the lowest-energy state as matter is compressed.
White dwarf: A compact stellar remnant supported against gravity primarily by electron degeneracy pressure. It is the clearest astronomical example of a star supported by degenerate electrons.
Fermion: A particle with half-integer spin that obeys Fermi–Dirac statistics. Electrons are fermions, so their statistical rules underlie the pressure.
Neutron degeneracy pressure: Pressure caused by the exclusion-driven filling of neutron quantum states in dense matter. It can support neutron stars, whose densities and particle composition exceed those of white dwarfs.
Fermi energy: The energy of the highest occupied state in a system of fermions at zero temperature. Compression raises the highest occupied electron energy, producing a pressure gradient.
Chandrasekhar limit: The maximum mass, about 1.4 solar masses, for a stable white dwarf supported by electron degeneracy pressure. Relativistic weakening of the pressure prevents electron support above this mass scale.
Fermi–Dirac statistics: The quantum statistical distribution governing identical fermions in thermal equilibrium. It describes how electrons fill available energy states in dense matter.
Radiation pressure: Pressure exerted by electromagnetic radiation as it transfers momentum. Radiation pressure depends on energy in a radiation field, unlike electron state filling.
Fermi gas: A collection of fermions whose behavior is described by quantum statistics, often approximated as noninteracting. The electron gas in dense matter is modeled this way to derive degeneracy pressure.
Type Ia supernova: A thermonuclear explosion that disrupts a white dwarf in a binary system. A white dwarf nearing its support limit can ignite runaway carbon fusion and explode.

Linked from 22 pages