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Ive never really understood spin in quantum mechanics for reasons explained in several other answers on Stack exchange. Would the confusion be less if the name of this quantum property was something with no easily pictured (but incorrect) classical correlate? For example, if spin had been named "wikiness" (as an example of a nonsense word, like "strangeness") would it be less confusing?

Richardbernstein
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    In early years Pauli's student (don't recall the name) derive the spin concept base on the idea that electron rotates around its axis. So I think there're lots of historical reasons to call it spin. And the physical nature (well, we still don't really know what it is, anyway) of it behaves more like angular momentum. So I wouldn't mind call it spin. And just accept it's an fundermantal quantum number of particles. Maybe Countt010's suggestion of spinlike or pseudospin can also stands (makes more sense accually) but spin is a lot shorter, easy to pronounce and used for a very long time. – Turgon Jan 28 '17 at 16:54
  • You are asking the world, presumably not confused by spin, if they are to provide an answer, whether you would be less confused by it, if it were called "wikiness"instead? Would you be less confused by it? How could a name confuse or unconfuse you? If it helps you understand commutator of the Lorentz group better, by all means, don't let anyone stand between you and the clarifying name. – Cosmas Zachos Jan 28 '17 at 22:29
  • @Richardbernstein, you should consider to accept one of the answers you've received. – AndreaPaco Jan 31 '17 at 09:28
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    I accept them all. – Richardbernstein Jan 31 '17 at 20:31
  • Please see What should I do when someone answers my question? – Thomas Fritsch Feb 14 '20 at 08:55
  • What you are asking is strictly a matter of opinion. Perhaps what you should really ask is "What is 'spin' in QM and how does it differ from the classical meaning?" – sammy gerbil Feb 15 '20 at 18:18

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It's really difficult to give a scientific and objective answer to a question of this kind, because what might confuses you could be very intuitive for someone else, and viceversa. Indeed we are talking about imagination, not about facts, laws, equations. Nevertheless in my opinion, interpretation is indeed important and is the key to real understanding.

I'll try to give you the reason for which spin is indeed quite a good word to use. First of all one should remember that spin is indeed an agular momentum. This is true not only from a dimensional point of view, but it's evident and comes out in many situations and experiments, for example the spin-orbit coupling, Stern-Gerlach experiment, etc. Since the quantum operator $\vec{L}$ is indeed an $\textit{orbital}$ angular momentum, meaning that it is defined as $\vec{r}\wedge\vec{p}$, people tend to identify the spin, at least pictorially, as an intrinsic rotation. In other words: if the Earth was a quantum object, its $\textit{orbital angular momentum}$ would be linked to the motion around the Sun, while its $\textit{spin}$ would be linked to the rotation around its axis. So, you'd better reserve other words, like "strangeness" or "wikiness" for phenomena whose essence has nothing to do with rotations and angular momenta.

AndreaPaco
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The name is here to stay, in my opinion. It is a source of confusion, unfortunately but also it is a reminder to QM newcomers that classical physics does not apply, despite the similiar languaguage and that math is more fundamental in the description of QM.

So it may balance out, for each student who thinks in classical terms, tries an exercise and learns from a mistake caused by a wrong assumption, there may be another who quickly grasps the idea that more thought is needed when dealing with QM and common sense is normally not a good guide.

This careful attitude to QM may then help save time later when dealing with other, more advanced, non-intuitive concepts.

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Imagine for a moment that Bohr never had suggested electron orbits and from the beginning were introduced volume shapes for each electron. And imagine that Pauli would have connected his exclusively principle (in an atom only two electrons can be in the same volume shape) with the electron's property to have a magnetic dipole moment.

Now remember all phenomena with the electrons spin - such as Stern-Gerlach experiment and emission spectra under the influence of an external magnetic field (hyper fine structure) - and exchange the term "electrons intrinsic spin" by "electrons magnetic dipole moment". If there wouldn't be any inconsistency in explaining all the phenomena by the electrons magnetic dipole moment then this two terms are synonyms and perhaps the usage of magnetic dipole moment is more intuitive.

HolgerFiedler
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