High School Neutron, White Dwarfs and Degeneracy Pressure

Click For Summary
Degeneracy pressure arises from the uncertainty principle, where confining electrons in a smaller space increases their momentum and velocity, leading to an outward pressure. This phenomenon is crucial in the formation of white dwarfs and neutron stars. The energy associated with this high velocity does not appear from nowhere; it originates from the gravitational potential energy of the particles before they reach the degenerate state. Therefore, the conservation of energy is maintained throughout the process. Understanding this relationship clarifies the mechanics behind degeneracy pressure in astrophysical contexts.
Jimmy87
Messages
692
Reaction score
19
Hi,

I have been trying to get some physics behind the cause of the degeneracy pressure but have some confusion with the stuff I have found. Apparently the cause of degeneracy pressure can be explained through the uncertainty principle. If you trap electrons in a smaller and smaller space the momentum becomes very uncertain and approaches the speed of light, hence causing an outward pressure. How does this explanation fit in with conservation of energy. It seems like trapping an electron suddenly gives it a very high velocity which seems to come form nowhere?

Any help is much appreciated
 
Physics news on Phys.org
If I'm not mistaken, I believe the energy comes from whatever you use to trap it in the first place. In the case of a neutron star or white dwarf, the energy would come from the particle's gravitational potential energy it had prior to dropping to the degenerate state.
 
  • Like
Likes Jimmy87 and Jilang
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

Similar threads

  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 109 ·
4
Replies
109
Views
6K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
3
Views
2K
Replies
67
Views
19K
  • · Replies 2 ·
Replies
2
Views
2K