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Copernicus
2014-Jan-23, 12:08 AM
I was explaining to my son that in the quantum realm that to some particles they can not tell something is there, but to other quantum particles that same something can seem like a 10 foot thick concrete wall. For example try pushing a proton through a brick wall. It stops. But a neutrino could go through a whole earth of brick and not notice a thing, except small deviations caused by gravity.
He asked me if an electron could travel through a proton or a proton through a proton. While I don't know the answer, and the forces are great. I guess I can't see that not happening either, most of the time. Although I would think the incidence of a collision would be much higher than for a neutrino colliding with the proton.
Does anyone know the answer to this?

EigenState
2014-Jan-23, 12:24 AM
Greetings,


I was explaining to my son that in the quantum realm that to some particles they can not tell something is there, but to other quantum particles that same something can seem like a 10 foot thick concrete wall. For example try pushing a proton through a brick wall. It stops. But a neutrino could go through a whole earth of brick and not notice a thing, except small deviations caused by gravity.
He asked me if an electron could travel through a proton or a proton through a proton. While I don't know the answer, and the forces are great. I guess I can't see that not happening either, most of the time. Although I would think the incidence of a collision would be much higher than for a neutrino colliding with the proton.
Does anyone know the answer to this?

Emphasis added. There is the Fermi contact interaction (http://en.wikipedia.org/wiki/Fermi_contact_interaction) as is well-manifested in hyperfine structure interactions involving ℓ=0 states. In such cases, the electron is considered to be within the nucleus--that applies to the hydrogen atom where the nucleus is nothing more than a proton.

Best regards,
ES

John Mendenhall
2014-Jan-23, 02:14 AM
t=0?

EigenState
2014-Jan-23, 04:02 AM
Greetings,


t=0?

Not t, lower case script L the orbital angular momentum quantum number--that is s-states.

Best regards,
ES

Copernicus
2014-Jan-23, 05:14 PM
Greetings,



Not t, lower case script L the orbital angular momentum quantum number--that is s-states.

Best regards,
ES

So I guess we are saying two electrons can occupy the same spot as long as their spin is opposite. If there is a x, y, and z component to the spin, how does that fit in?

EigenState
2014-Jan-23, 05:37 PM
Greetings,


So I guess we are saying two electrons can occupy the same spot as long as their spin is opposite. If there is a x, y, and z component to the spin, how does that fit in?

That is not at all what I said. The Fermi contact interaction treats a major component of observed hyperfine structure interactions, for s-states, as resulting from one electron being found within the nucleus.

It remains to you to decide if you consider that to be an example relevant to your initial question of whether "an electron could travel through a proton".

Best regards,
ES

Copernicus
2014-Jan-23, 05:40 PM
Greetings,



That is not at all what I said. The Fermi contact interaction treats a major component of observed hyperfine structure interactions, for s-states, as resulting from one electron being found within the nucleus.

It remains to you to decide if you consider that to be an example relevant to your initial question of whether "an electron could travel through a proton".

Best regards,
ES

Is there a simplified explanation for this?

Shaula
2014-Jan-23, 05:42 PM
So I guess we are saying two electrons can occupy the same spot as long as their spin is opposite. If there is a x, y, and z component to the spin, how does that fit in?
What it actually says is that no two electrons can occupy the same state. If you look at http://en.wikipedia.org/wiki/Spin_quantum_number#Derivation you see there are two quantum numbers associated with intrinsic spin, the primary one which determines the overall amount of it and the secondary one which determines what actual sub-state of the allowed spin states it is in. There are no quantum numbers associated with the other components of spin so they don't really come into this.

EigenState
2014-Jan-23, 06:09 PM
Greetings,


Is there a simplified explanation for this?

Probably not.

Best regards,
ES