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Questions tagged [pauli-exclusion-principle]

The Pauli exclusion principle states that two identical fermions, (so with half-integer spin) cannot occupy the same quantum state simultaneously, and thus share all of their quantum numbers. Also use for structure and classification schemes involving antisymmetry.

The Pauli exclusion principle states that two identical fermions, (so with half-integer spin) cannot occupy the same quantum state simultaneously, and thus share all of their quantum numbers. Also use for structure and classification schemes involving antisymmetry.

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How can I stand on the ground? EM or/and Pauli?

There is this famous example about the order difference between gravitational force and EM force. All the gravitational force of Earth is just countered by the electromagnetic force between the electrons on the surface of my feet and the ground. But…
Kivanc Uyanik
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Is Pauli-repulsion a "force" that is completely separate from the 4 fundamental forces?

You can have two electrons that experience each other's force by the exchange of photons (i.e. the electromagnetic force). Yet if you compress them really strongly, the electromagnetic interaction will no longer be the main force pushing them apart…
Jan M.
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Can bosons that are composed of several fermions occupy the same state?

It is generally assumed that there is no limit on how many bosons are allowed to occupy the same quantum mechanical state. However, almost every boson encountered in every-day physics is not a fundamental particle (with the photon being the most…
Friedrich
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Does black hole formation contradict the Pauli exclusion principle?

A star's collapse can be halted by the degeneracy pressure of electrons or neutrons due to the Pauli exclusion principle. In extreme relativistic conditions, a star will continue to collapse regardless of the degeneracy pressure to form a black…
kd88
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Why are planets not crushed by gravity?

Stars can be crushed by gravity and create black holes or neutron stars. Why doesn't the same happen with any planet if it is in the same space time? Please explain it in simple way. Note: I am not a physicist but have some interest in physics.
NotPhysicist
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What's the point of Pauli's Exclusion Principle if time and space are continuous?

What does the Pauli Exclusion Principle mean if time and space are continuous? Assuming time and space are continuous, identical quantum states seem impossible even without the principle. I guess saying something like: the closer the states are the…
Yogi DMT
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Why is the Pauli exclusion principle not considered a sixth force of nature?

Why is the Pauli exclusion principle not considered a sixth force of nature, given it produces such things as repelling of atoms and molecules in solids?
Anixx
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Why do neutrons repel each other?

I can understand why 2 protons will repel each other, because they're both positive. But there isn't a neutral charge is there? So why do neutrons repel? (Do they, or have I been misinformed?) The reason why I'm asking this is because, I've just…
Jonathan.
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What carries the information for the Pauli exclusion principle to occur?

I have been reading about the exclusion principle a little bit, but I have some questions about it. How does the information about the state of electrons get "passed around" so that other electrons in similar state can not have that same state? Is…
WDUK
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How does the Pauli exclusion principle create a force in degenerate matter?

My understanding is that when it comes to forming a white dwarf, it is the electron degeneracy pressure, due to the Pauli Exclusion Principle, preventing collapse in of the white dwarf. If the gravitational force is sufficiently large, then the…
Meep
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Are protons and neutrons affected by the Pauli Exclusion Principle?

I'm very confused about the Pauli exclusion principle. Wikipedia states it as "two identical fermions cannot occupy the same quantum state in a quantum system". I understand this for electrons that for each energy level in an atom there are two…
shA3245699
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Are fermions and bosons fundamentally different?

Looking at various particles regarding being fermions or bosons, it seems to me that fermions are something fundamentally different from bosons. What I mean by "fundamentally different" is "as different as the electromagnetic force is to the strong…
Volker Siegel
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Why does the conjugated $\pi$ bond not violate the Pauli Exclusion Principle?

Let's look at the molecule 1,3 butadiene: $CH_2=CH-CH=CH_2$ and number the carbon atoms 1 to 4 from left to right. The bonds between 1 and 2 and between 3 and 4 are double bonds: each constitutes a $σ_{2p}$ and a $π$ bond (molecular orbitals).…
Gert
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Does the Pauli exclusion principle instantaneously affect distant electrons?

According to Brian Cox in his A night with the Stars lecture$^1$, the Pauli exclusion principle means that no electron in the universe can have the same energy state as any other electron in the universe, and that if he does something to change the…
GordonM
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Big Bang and the Pauli Exclusion Principle

Due to some of the basic principles of quantum mechanics, we have the Wolfgang Pauli exclusion principle, where two fermionic bodies cannot occupy the same quantum state simultaneously. If that is true, then how is all matter, energy, space and time…
Siltogranio
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