ABSTRACT
In this chapter, the authors shall focus on the degenerate Fermi gas for which it is predominantly the lowest energy levels that are occupied by fermions. Expressions for the specific heat, the magnetic susceptibility, and the pressure of a Fermi gas are obtained and discussed. Although an ideal Fermi gas made up of non-interacting fermions may appear to be an extreme idealization, there are a number of systems to which the theoretical results apply as a good approximation under certain conditions. The number of discrete states in the Fermi sphere is equal to the number of states in the corresponding octant in quantum number space. Stars gradually burn up their light element nuclear fuel, which is the source of energy generation, through fusion processes. Neutron stars are much smaller in radius than white dwarfs and are composed of a degenerate Fermi gas of neutrons.
