What is Spin? A Geometric explanation

What is the spin of a particle? What is its geometric origin? What do the up and down states of electrons represent? All these answers in 20 minutes!

0:00 - Introduction
2:00 - Group theory
4:02 - State spaces
7:30 - Spin in Physics
10:26 - Quantum Mechanics
15:19 - The spin of an electron
18:22 - Summary and conclusion

This video is narrated by Octave Masson.
And if you liked this video, you can share it on social networks !

Alessandro Roussel,

_________________________________________________
_________________________________________________
To learn more :

[bendybruce]

This is the best explanation of quantum spin in a youtube video that I have ever listened to.

[eric]

Just finished my Master Thesis on differential spin geometry. I must say, your video really nicely explains the origins of spinors! really enjoyed it!!

[FigmentHF]

This is the first time I’ve had a tangible, intuitive understanding of this concept. So thank you, and well done

[ulti-mantis]

One example of a macroscopic object with spin ½ is USB thumb drives. Sometimes you need to turn it by 360° in order to plug them.

[Psrj-ad]

This channel is actually astonishing.
Its the only channel that can breakdown such absurdly abstract and complex topics into a form that's so clearly understandable. all without sacrificing "too much" of its initial complexity.

[prity]

All videos of ScienceClic should be given as a introduction for any student in physics, when exposed to these topics. This is just so intuitive, clear and well-built, like all the other videos, amazing!

[hoggif]

What a clear explanation! I like that this cover the idea of spin (unlike many videos of how spin is like rotation but not really a rotation which leave open what is is). Just enough group theory to get the idea without diving deep into it.
Absolutely best video of spin I've ever seen.

[alejrandom]

14:01 "The opposite of a quantum state is physically equivalent to it, although mathematically different" bro casually dropping the actual explanation we've been wanting for years

[DanielL]

Holey crap - this video connects math to physics in an understandable fashion without having to try to read through a 500 page tome of incomprehensible hieroglyphics. I always believed it could be done, but this channel finally did it. Technical and true without being inaccessible or insulting. Good job people. You did not put a spin on this.

[OblivionFalls]

I've been watching sci-educational YouTube for over 10 years and this is the first time I've ever felt like I have some understanding of what "spin" is. Damn good stuff, dude.

[nikankwon]

I've been getting obsessed with spinors for the last half-a-year and wow, what a fascinating conceptual entity. Without it, the entirety of electromagnetic fields, particle behavior and therefore the universe we are all familiar with wouldn't be possible (nor exist). It's a hell of a challenge learning it as a layman, but the fact that reality operates by these rules and we somehow figured out these hidden mechanics (there may be more we haven't discovered) is truly a remarkable achievement for our species, who've somehow gotten this far. Kudos to Dirac - a theoretical physicist I think that needs to be recognized and commended a lot more.

For those of you want to know more of the technical aspects of spinors, I found Richard Behiel's channel excellent. They are very long videos, but wonderful.

[aaaaaaaaaaaa]

20-minute video from ScienceClic? Let's fucking go

[novakastmusic]

I've never seen such an understandable explanation of spin.
All I've ever seen or read is "well it's not really spinning, it's just behaving like it is spinning", and then it gets increasingly complicated as they try to elaborate on that.
There's also that knot stuff and the mobius strip thing.
Very unintuitive.
Your explanation however
Mind blown

[LeTtRrZ]

An interesting fact that this video failed to mention: If you take the upper beam and send it through a horizontal magnetic field, it will split evenly left and right. If you take any one of those beams and send it through another up-down device, it will split evenly up and down, even though we originally used only the upper beam from the first split. However, if you were to properly recombine the left/right beams and send it through an up/down device, it would divert 100% up as it did before the left/right split.

[Memfyy]

Waking up to a ScienceClic video is something else! Excited to watch this!

[Ley-line]

Great video as always! Love the animations, and specifically how the 'collapse' is contrasted by fast movements while everything else has interpolation, nice subtle detail there. In general the analogies are simple to understand for such difficult to master topics. And the 3D and Space-Time grid representations have got to be one of the best ones out there.

[PhoticSneezeOne]

Am i the only one who´s getting unsettling existential dread feelings once the hypnotic music of scienceclic´s videos sets in?

[-_Nuke_-]

Best Science channel on YouTube period.

[plasmaflare]

Literally the best explanation that I have ever seen about spin in a Youtube video. Thank you so much for the video.

[johneagle]

Wow! This is the best explanation ever I've seen about spin.
No hand waving and silly analogies.
Thank you!!