The discussion revolves around the concept of spin in quantum mechanics, particularly focusing on what it means for two particles to have opposite spins. Participants explore the nature of spin, its measurement, and the implications of its directional properties, while expressing confusion and seeking clarification on these topics.
Participants generally agree that the concept of spin is complex and that visual analogies can be misleading. However, there is no consensus on the best way to conceptualize spin or its implications, and multiple competing views remain regarding its interpretation and measurement.
Participants acknowledge limitations in their understanding of spin, particularly regarding its measurement and the implications of its directional properties. There are unresolved questions about the relationship between spin and angular momentum, as well as the appropriateness of certain analogies.
hurricane89 said:if spin is a term used to describe a particles angular momentum, then how can something have an "opposite" angular momentum than another.
hurricane89 said:spin has me confused honestly. i barely know what it is or how its measured or why it isn't just called angular momentum
Vanadium 50 said:Spin has direction - it can be clockwise or counterclockwise, for example. Does that clear things up?
Matterwave said:That statement needs to be quantified since point particles (as far as we know) shouldn't be able to "rotate" about an axis. (so, clockwise, and counterclockwise may not be the best modifiers) Indeed, if you take and upper bound of the radius of an electron and use L=Iw=hbar/2 on it, and find the "velocity" of a point on the equator of the electron, you get a value that is over 10 times the speed of light.
Matterwave said:Yes, that's true, but my point was that "clockwise" and "counterclockwise" implies a rotation about an axis. Which demands further comments.
hurricane89 said:so now if theyre not rotating about an axis then how can something have opposite directions of spin. ughh what is it meant by "direction". is it the "direction" of spin which determines which way the particle curves in the magnetic field? even though it has nothing to do with rotation? if that's the case then "direction" doesn't even mean direction. it just means that "something" is different about electron A that makes it take one path while electron b takes the other... right?
are there any other ways to determine spin or is it just the stern-gerlach experiment which tells you that? thingd are starting to make senseDrChinese said:Yes, one has a spin value of +1/2 and the other is -1/2. It is confusing, because it is so tempting to think of a spinning golf ball or similar (you can probably guess what major tournament I was watching yesterday).
Keep in mind that positively and negatively charged particles also exhibit movement (attraction) and you don't need a picture of a spinning ball to picture that. Instead, you picture a magnet. Now, really, what does a magnet explain in this case? (Answer: nothing, it is circular logic as magnets are created by a special arrangement of their atoms.) The point is: with all particle phenomena, you CANNOT let the picture dominate your understanding. The picture is just a shorthand, nothing more, and even that only as long as it doesn't hold you back.