Electrons or neutrons (fermions)cannot have the same quantum numbers and therefore cannot be in the same place at the same time. In a neutron star the gravitational pressure forces these particles into very small cells, and therefore they must have very small wavelenghts, and very high frequencies. Particles that have very high frequencies can be thought of as having high velocity and energy analogous to E = hv = E=1/2mv2, and this neutron degeneracy pressure is what keeps the star from further collapse. However this force is strictly quantum mechanical if nature.

The reason fermions cannot occupy the same cell is because of the Pauli Exclusion Principle. Subatomic particles which are indistinguishable from one another follow completely different statistics from distinguishable particles. When 2 fermions with the same quantum numbers are put in the same state or place the resultant state vector is said to be antisymmetric (it changes sign) on the exchange of the particles which leaves a probability of zero that this can happen and it is this that ultimately produces the degeneracy pressure.

• Neutron Stars - Schnee - July 23, 1998 - 08:16 UTC
  • By the Way - Schnee - July 23, 1998 - 08:17 UTC
    • Neutron degeneracy pressure - RFL - July 23, 1998 - 12:50 UTC
      • pulsars - Schnee - July 23, 1998 - 13:16 UTC
        • Re: pulsars - RFL - July 23, 1998 - 15:44 UTC
          • Sorry I'm late in joining the party... - Astrophysicist - August 8, 1998 - 13:08 UTC
            • In continuation.... - Astrophysicist - August 8, 1998 - 17:20 UTC
          • I meant to ask you - Astrophysicist - August 8, 1998 - 17:23 UTC