Loading [MathJax]/extensions/TeX/AMSsymbols.js
Jump to content

Recommended Posts

Posted

No. Just the spin projection (spin up vs. spin down)

There is only one way for the quarks to combine and have it be a proton. There are two up quarks. They have to be anti-aligned in the ground state because of the Pauli exclusion principle 

Posted (edited)
  On 8/26/2018 at 6:46 PM, swansont said:

No. Just the spin projection (spin up vs. spin down)

There is only one way for the quarks to combine and have it be a proton. There are two up quarks. They have to be anti-aligned in the ground state because of the Pauli exclusion principle 

Expand  

Ok but then is it possible to change the magnitude of the spin of a electron and up quark (i know this would not be stable but for the limited time that it is would it be possible?)

Edited by Hami Hashmi
Posted
  On 8/26/2018 at 7:16 PM, Hami Hashmi said:

Ok but then is it possible to change the magnitude of the spin of a electron and up quark (i know this would not be stable but for the limited time that it is would it be possible?)

Expand  

No, spin is an intrinsic property, and is quantized. These are spin 1/2 particles.

Posted
  On 8/26/2018 at 10:55 PM, Hami Hashmi said:

Ok fine but for the sub-microsecond that they are together what will be the spin then?

Expand  

In a general scenario where you combine two spin-½ particles, the overall system would have either total spin 0, or total spin 1, with (I believe) equal probability.

  • 1 month later...
Posted

The only reason why i was wondering is because it is possible to change the angular momentum of a singularity (which is a point) so I thought it would be possible to do the same with two point particles using magnetism.

Posted

The angular momentum of a black hole is a property of the entire spacetime, and not of the singularity (which only arises in our models in the first place because we can‘t yet account for quantum effects). Furthermore, while spin can be considered a form of angular momentum, it is quite different from the one of macroscopic bodies.

Posted
  On 10/22/2018 at 4:51 AM, Markus Hanke said:

The angular momentum of a black hole is a property of the entire spacetime, and not of the singularity (which only arises in our models in the first place because we can‘t yet account for quantum effects). Furthermore, while spin can be considered a form of angular momentum, it is quite different from the one of macroscopic bodies.

Expand  

So you are saying that a singularity does not really exist?

Posted
  On 10/22/2018 at 9:39 PM, Hami Hashmi said:

So you are saying that a singularity does not really exist?

Expand  

Of course it does not physically exist - it‘s just a mathematical artefact of the fact that GR is a purely classical model, and hence cannot account for quantum effects.

Posted
  On 10/22/2018 at 10:17 PM, lucks_021 said:

A thing that I want to know, using this topic which comes to this subject, is:

If in a singularity, the time passes so slowly that for us (out of it) it would be infinite (since the singularity has infinite density) how can we observe the effects of the black hole angular momentum? (if you don't understand something, please ask me, my english isn't good)

Expand  

 

  On 10/21/2018 at 3:29 PM, Hami Hashmi said:

The only reason why i was wondering is because it is possible to change the angular momentum of a singularity (which is a point) so I thought it would be possible to do the same with two point particles using magnetism.

Expand  

The mathematical singularity where GR fails us, involves infinite spacetime curvature and infinite density, and this is why cosmologists do not believe it exists. Although we have no actual empirical evidence of what happens inside a BH, GR does tell us that once the Schwarzchild radius of any given mass is reached, further collapse is compulsory. But at the quantum/Planck level GR fails us, so it is I believe reasonable to assume that the mass resides somewhere at that level, before the infinities are reached. At the same time once any matter crosses the EH, it undergoes increasing stress [elongation/spaghetification] from the tidal gravity effects and depending on the size of the BH, will be broken down into its most basic fundamental parts, on its way to or at the quantum/planck/Singularity level. I think I have that reasonably accurate, if not someone who knows better can correct.

Posted
  On 10/23/2018 at 9:17 AM, beecee said:

 

The mathematical singularity where GR fails us, involves infinite spacetime curvature and infinite density, and this is why cosmologists do not believe it exists. Although we have no actual empirical evidence of what happens inside a BH, GR does tell us that once the Schwarzchild radius of any given mass is reached, further collapse is compulsory. But at the quantum/Planck level GR fails us, so it is I believe reasonable to assume that the mass resides somewhere at that level, before the infinities are reached. At the same time once any matter crosses the EH, it undergoes increasing stress [elongation/spaghetification] from the tidal gravity effects and depending on the size of the BH, will be broken down into its most basic fundamental parts, on its way to or at the quantum/planck/Singularity level. I think I have that reasonably accurate, if not someone who knows better can correct.

Expand  

Ok thanks. But if a singularity did exist, would my theory (post #10) be valid?

Posted
  On 10/23/2018 at 10:49 PM, Hami Hashmi said:

Ok thanks. But if a singularity did exist, would my theory (post #10) be valid?

Expand  

Are you asking if it is possible to change the spin of a (fundamental) particle like a proton? That has already been answered (no). 

So what is your question?

Posted
  On 10/24/2018 at 11:03 AM, Strange said:

Are you asking if it is possible to change the spin of a (fundamental) particle like a proton? That has already been answered (no). 

So what is your question?

Expand  

ok thanks that's what i wanted to know.

  • 1 month later...
Posted
  On 10/24/2018 at 11:03 AM, Strange said:

Are you asking if it is possible to change the spin of a (fundamental) particle like a proton? That has already been answered (no). 

So what is your question?

Expand  

not about total spin - which will remain 1/2 as per physics.

but if photon is absorbed by proton would not it change its spin state ?

Posted
  On 12/1/2018 at 10:53 AM, Rajiv Naik said:

not about total spin - which will remain 1/2 as per physics.

but if photon is absorbed by proton would not it change its spin state ?

Expand  

Since a photon is spin 1, yes, the spin state can change. Depending on the details of the interaction. 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.