# Two questions about electron's magnetic spin

1. Does electron's magnetic spin mean that we can think of it as having the two magnetic poles?

2. Does the spin mean that it generates magnetic field even if it is at rest?

I expect to get 'no' to both questions because we always say moving charges generate magnetic field. And I hope to see answers which will clear my confusion.

• Possible duplicate of physics.stackexchange.com/questions/9969/… but I wrote a short answer, as it seems more appropriate for the OP to learn more from. (Hopefully) – user214814 Dec 2 '18 at 22:25
• @physicsguy19: the answer by Hans de Vries present in the link cited by StudyStudyStudy contains the answer to your question. n.2. The wavefunction of a charged particle with a non-zero spin carries a current which explains the magnetic dipole of the electron. – GiorgioP Dec 2 '18 at 23:03
• Thank you. Actually I'm so happy to get a 'yes' for both questions 👍 I love this site. – physicsguy19 Dec 3 '18 at 6:01

The electron can be seen as a small magnet with the field of a magnetic dipole of strength $$2\mu_B \vec S$$. So my answer is yes in both cases. I interpret as at rest a state in which the electron has zero momentum expectation value. Note that there is no accepted model of spin as a rotation, although spin is an angular moment to every effect.

• does it mean that when an electron is released (with zero speed classically) in a uniform magnetic field, it just aligns its magnetic moment with the field and does no translational motion (classically)? – physicsguy19 Dec 3 '18 at 8:05
• Yes, that is correct. – my2cts Dec 3 '18 at 8:22
• @my2cts: which one is correct?:) sorry.. – physicsguy19 Dec 3 '18 at 8:47
• @StudyStudy No motion or translation will occur in a uniform field. – my2cts Dec 3 '18 at 9:23
• It will move as the field is nonuniform. In your original question you assumed a uniform field. – my2cts Dec 3 '18 at 12:59

Does electron's magnetic spin mean that we can think of it as having the two magnetic poles?

Yes. There are no known magnetic monopoles, see: Magnetic Monopoles

Does the spin mean that it generates magnetic field even if it is at rest?

Yes, but as regards "at rest", you should read this answer: Electron at rest

Magnetic spin isn't really a proper term, but an electron's spin is directly linked to its magnetic field, if we were to say that only moving electric charges produce magnetic fields, we would have trouble explaining how a static magnetic "works".

I would also stress that spin in this case is purely a mathematical idea, an electron does not resemble a very small rotating football in this case, its a bad choice of words made years ago.