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This is the pressure that prevents a white dwarf star from collapsing. A star exceeding this limit and without significant thermally generated pressure will continue to collapse to form either a neutron star or black hole, because the degeneracy pressure provided by the electrons is weaker than the inward pull of gravity.
Quantum-mechanical electron degeneracy pressure in a block of copper [83] 48 GPa Detonation pressure of pure CL-20, [84] the most powerful high explosive in mass production 69 GPa 10,000,000 psi Highest water jet pressure attained in research lab [85] 96 GPa Pressure at which metallic oxygen forms (960,000 bar) [81] 10 11 Pa
Using the Fermi gas as a model, it is possible to calculate the Chandrasekhar limit, i.e. the maximum mass any star may acquire (without significant thermally generated pressure) before collapsing into a black hole or a neutron star. The latter, is a star mainly composed of neutrons, where the collapse is also avoided by neutron degeneracy ...
While degeneracy pressure usually dominates at extremely high densities, it is the ratio between degenerate pressure and thermal pressure which determines degeneracy. Given a sufficiently drastic increase in temperature (such as during a red giant star's helium flash ), matter can become non-degenerate without reducing its density.
This pressure is called the electron degeneracy pressure and does not come from repulsion or motion of the electrons but from the restriction that no more than two electrons (due to the two values of spin) can occupy the same energy level. This pressure defines the compressibility or bulk modulus of the metal [Ashcroft & Mermin 8]
Conversely, two or more different states of a quantum mechanical system are said to be degenerate if they give the same value of energy upon measurement. The number of different states corresponding to a particular energy level is known as the degree of degeneracy (or simply the degeneracy) of the level.
where T is the temperature, P is pressure, V is volume, and μ is the chemical potential. Boltzmann's equation S = k ln W {\displaystyle S=k\ln W} is the realization that the entropy is proportional to ln W {\displaystyle \ln W} with the constant of proportionality being the Boltzmann constant .
Griffiths has a problem in the same section, to show how 3/5 of bulk modulus of a copper is close to the degeneracy pressure. Assuming I did the problem correctly, if 2 free electrons per copper atom are assumed, the relation becomes almost exact.