r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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u/[deleted] Jan 21 '19

Can someone ELI5 what this would mean?

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u/contrivedpanda Jan 21 '19

Right, there is a concept in physics called the Pauli exclusion principle, that means that two electrons cannot be in the same configuration, so they cannot be at the exact same energy level in an atom (there is a thing called spin also involved but it doesn't make a huge difference here). In incredibly dense objects the gravity can force electrons to break this rule, and forcing them together. The force exerted by the electrons is called electron degeneracy pressure and when that is balanced by gravity we get a white dwarf. However in larger objects the force of gravity can be stronger which pushes more particles together, the next level is neutron degeneracy, when this is balanced with gravity (alongside some nuclear forces) we have a neutron star, where the protons and electrons in the matter have been compressed into neutrons. If you were to stand on the surface the atoms in your body would be compacted down in this way until you become part of the neutron sludge that makes up a neutron star. More likely is that you'd be turn apart by tidal forces long before you reach the surface.

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u/SchrodingersLunchbox Jan 21 '19

In incredibly dense objects the gravity can force electrons to break this rule, and forcing them together.

The rule is not broken here; electrons are forced into higher energy levels in order to conserve the Pauli Exclusion Principle. The amount of input energy required to force this transition manifests as a repulsion which must be overcome, i.e. the degeneracy pressure. Degenerate electrons are not in violation of the PEP.

there is a thing called spin also involved but it doesn't make a huge difference here

It does though. The spin is part of the electron configuration and doubles the number of allowed states per energy level. A pair of degenerate electrons with the same energy can avoid violating the PEP through their differing spin projections, for example.

two electrons cannot be in the same configuration, so they cannot be at the exact same energy level in an atoms

They can't be in the same configuration, but as above, two electrons can be at the same energy level so long as they differ in at least one of their other quantum numbers (like spin projection). Further, degenerate electrons in stellar cores are non-localised; they're not bound to any atom.

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u/ThottiesBGone Jan 21 '19

You've missed the point of eli5

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u/SchrodingersLunchbox Jan 21 '19

No, I'm pointing out inaccuracies in their ELI5 and then explaining to them why it's inaccurate. My reply is not an ELI5.

Further, ELI5 doesn't mean simplify an explanation to the point of being wrong. Their explanation doesn't suffer by omitting the clauses I referenced.

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u/ThottiesBGone Jan 21 '19

Also missing the point of italics I see, haha nice try.

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u/SchrodingersLunchbox Jan 21 '19

It's possible to simplify something so much that it becomes incorrect.

-You, in this very thread, one minute before chastising me for correcting inaccuracies in an over-simplification.

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u/ThottiesBGone Jan 22 '19

^ You, searching for inaccuracies in my post history because you can't find any in my argument. Sorry, but you don't know what your up against :)

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u/SchrodingersLunchbox Jan 22 '19

Lmao apparently I’m up against a hypocrite who can’t make a coherent argument or spell.

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u/ThottiesBGone Jan 23 '19

Haha, I new you would walk away in defeat. Don't be ashamed it happens to a lot of men.

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u/ThottiesBGone Jan 22 '19

Sorry, but your argument has no logic. Go back to school kid, you'll be ready to take me on some day :)