Does a stationary electron have a magnetic field?

In summary, a stationary electron does have an associated magnetic field due to its inherent quantum property of spin, which is aligned with its magnetic moment. This relationship is consistent with other particles with non-zero spin and is not accurately predicted by modeling the electron as a classical sphere.
  • #1
falcon32
81
0
At first glance, it seems that, no, a stationary electron would not have a magnetic field associated with it, since we know that fields arise because of moving charges.

However, if I understand the current description of the electron, it has an inherent quantum property called spin. This is nothing like what we normally think of, as in the spinning of a classical sphere around an axis of rotation (since then the electron would need to be spinning with an angular velocity far greater than the speed of light, which is impossible), but nevertheless, can give rise to a magnetic moment.
(http://hyperphysics.phy-astr.gsu.edu/hbase/spin.html)

But aren't magnetic moments associated with respective magnetic fields via the Biot-Savart Law? For example, we see that Earth has both a magnetic moment, and a related field; in fact everywhere we see magnetic fields, and we can find out their related magnetic moments.
(http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/biosav.html)

So does an electron have an associated magnetic field because of its inherent quantum property of spin?
And if it does not, then why does it display this deviation from what seems to be a dual relationship seen throughout nature?

Thanks for helping me figure this out.

(note: this is an unanswered question from one of my previous threads)
 
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  • #2
A magnetic moment that doesn't produce a magnetic field is a contradiction in terms. A stationary electron does have a magnetic moment, which produces a dipole magnetic field around the electron. The magnetic moment is aligned with the electron's spin, and the two are related. I think that in general any charged particle with nonzero spin will have a magnetic moment aligned with its spin.

A spinning classical charged sphere of finite radius also has a dipole moment aligned with its spin and will generate a magnetic field. If you try to model the electron as a classical sphere like this, however, you will predict the wrong value for the gyromagnetic ratio.
 
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  • #3
The_Duck said:
A magnetic moment that doesn't produce a magnetic field is a contradiction in terms. A stationary electron does have a magnetic moment, which produces a dipole magnetic field around the electron. The magnetic moment is aligned with the electron's spin, and the two are related. I think that in general any charged particle with nonzero spin will have a magnetic moment aligned with its spin.

A spinning classical sphere of finite radius also has a dipole moment aligned with is spin and will generate a magnetic field. If you try to model the electron as a classical sphere like this, however, you will predict the wrong value for the gyromagnetic ratio.

Ok awesome, thanks for clarifying that...I had suspected as much, but was worried that if I out and said it, someone would bite my head off for being wrong, so I phrased it as a question. My head takes time to regrow :)
 

1. What is a stationary electron?

A stationary electron is an electron that is not in motion or moving at a constant velocity. It is at rest in a particular position within an atom or molecule.

2. Does a stationary electron have a magnetic field?

Yes, a stationary electron does have a magnetic field. As an electron spins on its axis, it creates a magnetic moment, giving the electron a magnetic field.

3. How is the magnetic field of a stationary electron different from a moving electron?

The magnetic field of a stationary electron is weaker than a moving electron. This is because the strength of the magnetic field is directly proportional to the velocity of the electron. A stationary electron has no velocity, therefore its magnetic field is weaker.

4. Can a stationary electron be affected by external magnetic fields?

Yes, a stationary electron can be affected by external magnetic fields. The magnetic field of a stationary electron can align with an external magnetic field, causing the electron to experience a force and potentially move.

5. How does the magnetic field of a stationary electron play a role in everyday life?

The magnetic field of a stationary electron plays a crucial role in modern technology, such as in the functioning of computer hard drives, MRI machines, and particle accelerators. It also plays a role in the Earth's magnetic field, which protects us from harmful solar radiation.

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