Search results
Results from the WOW.Com Content Network
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.
Degeneracy pressure keeps dense stars in equilibrium, independent of the thermal structure of the star. A degenerate mass whose fermions have velocities close to the speed of light (particle kinetic energy larger than its rest mass energy ) is called relativistic degenerate matter .
Some massive stars collapse to form neutron stars at the end of their life cycle, as has been both observed and explained theoretically.Under the extreme temperatures and pressures inside neutron stars, the neutrons are normally kept apart by a degeneracy pressure, stabilizing the star and hindering further gravitational collapse. [2]
Stars above the limit can become neutron stars or black holes. [7]: 74 The Chandrasekhar limit is a consequence of competition between gravity and electron degeneracy pressure. Electron degeneracy pressure is a quantum-mechanical effect arising from the Pauli exclusion principle.
In massive stars, the core is already large enough at the onset of the hydrogen burning shell that helium ignition will occur before electron degeneracy pressure has a chance to become prevalent. Thus, when these stars expand and cool, they do not brighten as dramatically as lower-mass stars; however, they were more luminous on the main ...
In a star less massive than the limit, the gravitational compression is balanced by short-range repulsive neutron–neutron interactions mediated by the strong force and also by the quantum degeneracy pressure of neutrons, preventing collapse. [12]: 74 If its mass is
They spend several billion years on the subgiant branch, with the mass of the helium core slowly increasing from the fusion of the hydrogen shell. Eventually, the core becomes degenerate, where the dominant source of core pressure is electron degeneracy pressure, and the star expands onto the red giant branch. [9]
An exotic star is a hypothetical compact star composed of exotic matter (something not made of electrons, protons, neutrons, or muons), and balanced against gravitational collapse by degeneracy pressure or other quantum properties. Types of exotic stars include quark stars (composed of quarks)