Spin in Quantum Mechanics: What Is It and Why Are Electrons Spin 1/2? Physics Basics

[@ParthGChannel]

Hi friends! Thanks so much for watching this video. I'd like to thank the sponsor, Skillshare - check out Skillshare Premium for free at this link: skl.sh/parthg11201 Also, if you enjoyed this discussion of spin then feel free to subscribe to my channel for more fun physics content. As always, thank you for your wonderful support!

[@itsbk6192]

Dude. This was awesome. Keep it up

[@sharma_anuj00]

I guess you are an Indian?

[@swarnenduroy668]

Hi Parth, awesome videos. I had some questions regarding your video on diffraction. Is there any way to address you personally? thanx heaps

[@akashsunil7464]

mr. parth can u make a new video its already been one week

[@akashsunil7464]

i mean i wanna learn something new

[@ArvinAsh]

Nice explanation. Well done!

[@ParthGChannel]

Thanks Arvin, love your videos! :D

[@weaversinstitutebydeveshji730]

And i love both of your videos.. A big Thank you and love from India.

[@dhanashrikulkarni5878]

Hey Arvin! Love your vidoes!❤

[@It.was.always.you.vedddd]

Llove you Arvin

[@शिवोहम-श2व]

Two finest physicist 🤩

[@PrettyMuchPhysics]

The way I like to think about spin is that it's just some inherent property of a particle, like mass. But unlike mass, which is a scalar, spin is a vector quantity (i.e. 3 components), which obey the same maths as angular momenta do!

[@DrDeuteron]

that works for integer spins.

[@spikkelkip8128]

Mass isn't an inherent property of particles though.

[@blinded6502]

@@spikkelkip8128 Mass is internal momentum

[@AdrienLegendre]

For the simplest non-trivial representation, spin 1/2, spin is a spinor.

[@wayneyadams]

These are the most useful videos I have seen anywhere. They use simple direct explanations and examples, and also discuss possible misconceptions. Even though I am retired after teaching Physics for 33 years, I still like to see how other people teach these concepts, and as I said, these are the best I have seen. Anyone who wants to gain a solid education in the basics of physics can do so with these videos.

[@tejasgowdakr4700]

Thank you so much You gave me hope!

[@nadinesereda-sass158]

I read your description and you seem like the worlds most unlikable and close minded person.

[@cyto3338]

I tried a lot of spin explainer videos and sites, this here is the best one on internet (it is amazing that you uploaded the video right when I was having problem with the topic)

[@jeffeejenson707]

Omg..the evolution of ur hairstyles is funny man😂..

[@tmhood]

I suspect that Parth's hair is a quantum system. It exists in a superposition of states, only collapsing into a particular style when observed on KZbin.

[@jeffeejenson707]

@@tmhood 😂

[@Internetlo]

I’m reading The Amazing Story of Quantum Mechanics by James kakalios & I found this concept so interesting & came across your channel. Thank you for explaining this 🙏🏼 I’m a nurse but I wanna go back to school for physics now 😤All of this is so fascinating

[@georgedoran9299]

It definitely possible, one of my friends in my year at uni did a full medical degree and worked as a doctor for 2 years then switched to physics

[@genericusername1243]

first time yt algo recommended a vid thats 10mins from its upload rather than 10 yrs and im not even sub to this channel yet. anyways good video here 👏

[@damnboi972]

Me: "gonna learn today what spin is " Someone : "what is spin?" Me: 🤷

[@shayanmoosavi9139]

Also every physicist : 🤷‍♂️🤷‍♂️

[@Reddit_database]

Everyone - 🤷‍♂️🤷‍♂️🤷‍♂️

[@jimjohn8581]

You explain physics better than anyone else on KZbin. Point blank

[@kA-dc6zq]

I'm an English teacher but I read philosophy on my own. I also read about quantum to make a deeper view of the universe. Now, I'm reading Beyond Weird by Philip Ball. When I don't understand some difficult parts like spin, I watch these suggestive videos. They are amazing for us beginners. Thanks a lot.

[@olijacobs3347]

Please do the Dirac equation

[@mudkip_btw]

Yes please!

[@ashokb9456]

The best thing about your videos is that you explain even the tiniest things in a very detailed manner which is really helpful .Thanks a lot😊

[@dalirkosimov4623]

3:08 using the right hand rule, shouldn't up be counterclockwise while down be clockwise?

[@josephtraverso2700]

This is applying to electrons with a negative charge so we use the “left hand rule”. It essentially reverses the outcomes of the right hand rule used for positive particles

[@RussellSubedi]

@@josephtraverso2700 Shouldn't angular momentum be independent of charge?

[@josephtraverso2700]

@@RussellSubedi angular momentum is a a vector quantity. Charge is a scalar that is applied to it. Thus, changing the sign of the charge would flip the vector around making the RHR backwards

[@RussellSubedi]

@@josephtraverso2700 But doesn't that make the magnetic dipole moment of the electron positive for positive angular momentum, but that and the angular momentum must have opposite sign? I'm having problems phrasing it, but I hope you get my question.

[@nirbhaykumarchaubey8777]

@@josephtraverso2700 thanks buddy

[@Jas3nM]

That disallowed spin 0 photon NEEDS its own explanation!

[@DrDeuteron]

gauge invariance gobbles it up.

[@Sujay.Vaidya]

This is the most easiest and effective explanation of spin. Well done Parth!

[@saisuneeth8168]

can we consider that diffraction also happens due to heisenberg uncertainty principle. cause we can also think that photons angular momentum changes (bends) due to decrease in distance in double slit experiment. can it happen like that? this is a question from your diffraction video.

[@vitorgracia5113]

partly yes, i believe, constraining spin in light is polarization, and as far as i remember from a feynman lecture the diffraction event can be explained in the double slit experiment by HUP. As you constrain the possible positions the particle can take, by tightening the slit, and as (∆h/4π ≤ ∆x.∆p) , then a sufficiently small gap requires a larger momentum variance in order to mantain the equation true, so its direction increases in spread.

[@saisuneeth8168]

@@vitorgracia5113 thanks

[@yilizhang790]

Firstly, thanks a ton for the detailed discussion on this topic! It all makes sense except at 10:18: Why not stop at -1/2 h since you have already hit negative here?

[@yilizhang790]

Oh, I think I get it! By negative limit, you mean the negative counterpart of the maximum positive momentum, right?

[@BRUH-pv9rb]

@@yilizhang790 i have the same doubt and i think u r right bro 👍

[@Saralcfc]

I had the same question

[@Jonathan-rr9ed]

holy grale what a yt cannel feels great to have found u!!!

[@EpziWasHere]

Ive watched this and your video on "Why Spin Matters" and now understand Spin more thoroughly than from any other source Ive found in *years* of trying to understand this thing!

[@SWBarua]

It was really helpful. Please make a video on isospin.

[@cofa4011]

Amazing content man ! :D Thanks you very much for sharing ! I'm a total noob didnt even graduate but i'm wondering is the spin actually "carrying" the energy of the particule or is it only a way to describe a behaviour of a particule that fits both quantum mechanics and special relativity ? I hope my question makes some sense ^^'

[@dhanashrikulkarni5878]

I absolutely love your videos Parth! Just to tell you, I am 12 and I just adore your videos!

[@hk3676]

Im 12 and think u dumb

[@beyondhumanrange6196]

u know what quantum physics is ?

[@aarohanyt7374]

Underrated video💙

[@asifalamgir5135]

Awesome Editing man ... Much Better than Previous videos. Well Done!!!

[@johnpaulbounce3708]

It's just like attending to my college quantum class, but more juicier and spicier. Thanks. Wonderfully explained.

[@kevinmccarthy8746]

I am newly introduced to Quantum physics, particle physics and I like to review all the incredible aspects of Quantum Mechanics like the first time I read about the Double Slit Experiments, the Quantum Entanglement experiments, I ,was just amazed. So amazed in fact I instantly regretted ever having played sports. So I love to review say SPIN or ANGULAR MOMENTUM and go through a lot of different video`s on that subject to see the different ways they present their information. Which is more comprehensive for me than just one presentation of the subject matter. Then I can take a brake and review some video`s on Quantum Chromodynamics for instance. Very fun and relaxed at my own speed so to speak.

[@reznovvazileski3193]

Thank you, finally :') This is what a high school teacher, a chemschool teacher and 3 college professors couldn't manage to tell me really? :') I mean they probably told me the most of it but I always got the story of yeaa it's called spin but it's not really spinning and it's a magnetic constant of sorts. Which is all nice and stuff but the little detail that slipped there is that it's a result of this implicit angular momentum, that clears up the entire picture for me :')

[@nvmffs]

But it doesn't have angular momentum, just to clear any confusion

[@wayneyadams]

3:16 Curl the fingers of your right hand in the direction of the spin and your thumb gives the direction of the spin vector.

[@danjbundrick]

Your videos are as informative as they are fascinating. Thank you for sharing your knowledge and illustration skills!

[@Skeletone56]

WE ACHIEVING THE GOLDEN RATIO WITH THIS ONE 🗣🗣🗣🗣🗣🗣🗣🔥🔥🔥🔥🔥🔥💯💯💯💯💯💯💯

[@mostafaabdelhamid8653]

MAZING THANKS REALLY, WONDERFJL EXPLANATION

[@judemetcalf4265]

Such a great video on such a complex and misunderstood phenomenon. I have always had trouble understanding spin, and have read, watched and heard so many conflicting and unhelpful explanations, but this truly was useful. Love your videos

[@aintgonnatakeit]

This is my favorite explanation of this!!

[@larrystone654]

5:44 I wish you would write a book. Your explanations are clearer and more intuitive than any of the popular physics books I’ve read. Please consider it!

[@icyy-_-warrior1650]

You are amazing! People use the word magnetic and that can get in the way of learning. Thank you!

[@asnbman]

Wow! This video was awesome! Thank you. Can you teach our teachers how to teach?

[@akshatgaur84]

Thank you , awesome video.

[@nemesiswes426]

Great Explanation, not a lot of other physics video's explain things nearly as well as you do.

[@gaurvsinha]

I'm trying to learn Quantum Computation. I'm using your video to understand the concept of Quantum Mechanics and how these concepts are using in Quantum Computer. Thanks you such a quality video.

[@jeromemanceau4263]

Ooohh!! Looking forward to be watching more of your stuff!

[@sunithasomalingam2668]

Lots of Love❤️

[@danielsayre3385]

Damn this video was helpful. Thank you for the immense number of references toward resources... subbed. Thank you, seriously thank you

[@abhishekprasad6350]

Nice video. Fun fact-Nothing in the universe rotates on its axis even the earth,if u think hard u would get that as earth is made up of atoms,molecules and compound they revolves together in a particular direction making it look like rotation on axis on a macroscpic level🙃

[@waynelast1685]

Nice overview for someone new to spin

[@jimmypk1353]

The BEST explanation I've found so far. Succint, precise, no fancy effects/graphics. Brevity is the soul of wit!

[@bernardolozano7429]

Underrated video and channel, good job

[@laranjajefessor]

Very cool! I was thinking about the spin of an electron and how it makes it change its path in the presence of a magnetic field. And that's exactly what happened on tube TVs!

[@alhasan586]

Hey, I like your videos. I want to one thing and that is, " Rutherford model big mistake was Maxwell law which says if electron spin constantly it will lose power and fall inside nuclease" I want to know the deep of these theory

[@vulpecula182]

.. Interested

[@captainshipman7377]

That’s saying if electrons orbit the nucleus, they would lose energy as radiation and “fall” into the nucleus. That’s how we know electrons don’t orbit atoms. But quantum spin is different. That’s why De Broigle thought that electrons were standing “waves” instead. Like photons, electrons are also subject to wavelike behavior.

[@crimsoncanvas51]

I came to your channel last 10days and now I see your explanation of topic in simple ways. Wish my school teacher, college professor taught physics in such intuitive ways. Great explanation of each topic. Can you make separate video on quantum states? N, l, m and s, electonic configuration etc.

[@yenyelinito]

Love from Puerto Rico!

[@yasmincheani4633]

Thank you so much. This really help me understand better especially electron spin 👍😀

[@nishatiwari9212]

Angular momentum

[@jakelyle5663]

Great video!

[@davidianmusic4869]

Thank you, very clear and deep description.

[@ninadgadre3934]

KZbin threw this channel at me and I am thankful! Awesome stuff, Parth, looking forward to consuming all your vids!

[@arekkrolak6320]

Very good and informative video, I will surely check more!

[@FD-rt3rv]

you just explained clearly in a 12 mins video something my well paid professor cannot explain in a full semester. something seems to be wrong with the system

[@chrisstargazer5866]

Amazing. Love your explanations .

[@dylenweerasekara9533]

Thanks Parth. You've always been a good physics teacher to me. Thanks for giving this free info to teens like me.

[@gethnoble4316]

Semoga bnyk skses dgn channel ini!

[@dinghanxue704]

Need to know why spin occurs

[@DrDeuteron]

b/c all fields (particles) transform as some representation of the Lorentz group (that's math). Physically, it means it's the geometric thing that is compatible with special relativity, i.e., has no rest frame and has the same physics, regardless of motion.

[@zeio-nara]

Thank you a lot for a clear explanation. Don't know any place where the electron spin is explained more accessible.

[@bhcontraction]

I come hete because I wanted yo understand more about the muon g-2 experiment and in order to understand that, have to understand "spin" first😂

[@playerraja2483]

Subscribed. Thanks

[@hellboy_____2019]

Thank you 3000, for this topic you have selected

[@rmawn2816]

Thank you so much

[@karthikk4831]

i am waiting long time parth thank you

[@mdsaddamhossain3565]

You are an awesome Explainer, Teacher. Thank you.

[@anuragkashyap9888]

Excellent explanation .

[@priyapk1017]

Thanks Parth 💜

[@IdeasOfAjit]

Thank you Parth for the video.

[@ajhcornwall]

Thanks for the video, but although you say a few times “but the particle is not actually spinning, it just behaves as if it’s spinning”, you don’t answer the very obvious question which is “why are you so insistent that the particle is not actually spinning?”, I would really appreciate if you could answer this.

[@kidzbop38isstraightfire92]

So theres two reasons I've heard, with the second making the most sense: 1) its a point particle, meaning that there is no surface/volume to do the spinning; 2) one "revolution" of spin does NOT return it to its original position. It actually takes two revolutions, and they call this a Spinor. There is a video by PBS Spacetime on Spin and spinors thats really good, I suggest watching it

[@ajhcornwall]

@@kidzbop38isstraightfire92 thanks. I think I watched that PBS video. But whilst I appreciate the spin 1/2 characteristic rules out something simple like a spinning top, I don’t see why it necessitates making the leap to thinking of spin as an abstract property that has no physical meaning, I.e there is not something going around and around with a twist

[@kidzbop38isstraightfire92]

@@ajhcornwall agreed on why it doesn't rule out a physical spin...I actually think there is a physical spin (granted, I'm a casual physics follower so I dont know what I'm talking about), but I guess the point is that it doesnt follow conventional spin rules, according to most physicists.

[@michaelfox6831]

Wolfgang Pauli said regarding quantum mechanics, "the best that most of us can hope to achieve in physics is simply to misunderstand at a deeper level"

[@xephyr417]

​@@ajhcornwallI had the same thought. It seems as tho someone made a calculation a long time ago and said "if it were spinning, the surface has to be moving faster than the speed of light" so it can't be. But they assumed it was a sphere for that calculation. As far as I have found there are no other reasons to say spin isn't actually rotation, but I could just be wrong.

[@uthpalaweerasooriya4839]

Thank you💚

[@abdulrahmanalhamali1707]

Great video, thanks!

[@afriedrich1452]

Yes, that is all well and good, but "what" exactly is spin? And why do electrons have to spin around twice in order to spin around once?

[@ajhcornwall]

I don’t think he knows. And I don’t think mainstream physics has a clue either. And it bugs me that people like this can’t be more honest that they don’t have the foggiest idea how everything fits together. They like to present themselves as know-it-all experts.

[@afriedrich1452]

@@ajhcornwall Oh, I think he knows. He just doesn't want to tell us because he thinks we can't handle the truth.

[@br3nto]

4:57 Is there an experiment in which the measurement apparatus aligns to the particles spin axis?? It would be fascinating to see what would happen if we could measure a particles spin axis orientation multiple times over a distance to see how it changes. How much does the spin axis orientation change? How much is the spin axis affected by external forces? If we measure entangled particles, how long does it take for external forces to cause drift in the axis alignment of the entangled particles? Does the spin axis precess like a plants axis, or does it rotate along one or more axes? Etc etc

[@br3nto]

5:57 I’m assuming this is because when the particle enters the magnetic field, its spin axis orients based on the magnetic field? Is the orientation 100% aligned, or is there still rotation and precession in the spin axis?

[@br3nto]

7:07 is that magnitude based on the speed of light?

[@br3nto]

8:01 a quick google suggests that we have never encountered particles with spins other than 1/2 or 1. All other spins are theoretical. Is that true?

[@br3nto]

What do you think of Vivian Robinson’s particle model that describes spin?

[@lysiri12]

You’re amazing! 🙌🏼

[@laughinggooner4271]

If you didn't mention that special relativity being compatible with quantum mechanics I would never have known. I am not surprised that fermions and bosons have this half spin difference. I came to this video thinking that spin is some way affects these two groups of particles. My hypothesis was leaning towards the effect of spin on mass.

[@jabbariqra6097]

In a job interview ,sometimes it is asked to write three forms of Heisenberg uncertainty principle.I thought that they asked just to confuse the candidate🤭🤭.. I really did not know about its third form.. Thank u Mr

[@arekkazmierowski9657]

Great vid as always. But puzzled about so much advertising. While I understand why it is there, I have a problem with it paying for YT Premium every month to get rid of ads and still support creators...

[@abeersingh8855]

Didn't understand that concept 10 minutes ago now i do, thanks

[@nevermindnever8363]

1.Why is it that we subtract the spin by 1? 2.Why can't we go further with the subtraction after reaching the -ve value of n? 3.How do we know the initial spin number? 4.Why are they either whole numbers or integral multiples of half?

[@trcunni]

Thanks!

[@ParthGChannel]

Thank you very much!

[@YashRaj-ix1dp]

Please make a video about solitons.

[@jefsof117]

motion itself is the fundamental quanta - all forces and matter are made of it, tightly bound little spinning spheres of pure motion force

[@sisyphus645]

I have a simple analogy that can easily explain this concept. Imagine a sphere. Now imagine the sphere turning. That is spin. Except, it's not a sphere and it is not turning

[@JAUNEtheLOCKE]

HAHAHHAHAHAHHAHAHAHAH

[@sisyphus645]

@@JAUNEtheLOCKE Hey, I took the liberty of going through your channel. I must say, you're very fucking talented it's unbelievable. How old are you????

[@hoggieboggie5936]

SUBSCRIBED!😀

[@ricardodelzealandia6290]

Nice, and not too dumbed down.

[@saketrane8295]

love ur content thnx

[@preranadash9640]

You are the best:)

[@vedanglad1767]

I think you might have flipped the direction of the spin at 3:13, by the right hand rule

[@greensombrero3641]

Imagine it's a ball and it's spinning - except it's not a ball and it isn't spinning

[@Kjetilstorm]

The wilder the hair, the more trustable the science source.

[@ishukhneja]

At 3:14 if I see in different direction then it would be anti clock wise. it's relative. So how we would differentiate up and down spin

[@ahmcarri]

thank you :D

[@prashantlale4976]

Boy you are amazing physics guy ♥️

[@shikhamishra3238]

It could be more basic from learning point of view !! Anyways I enjoyed it.

[@Eztoez]

Agreed. If you can't explain something you are either a poor communicator, or, you don't actually understand it. Try explaining it so that your grandmother understands it. Tell me its angular momentum doesn't help. Telling me about quantum entanglement doesn't help. Just tell me what it actually is. Telling me its called spin but that the particle doesn't spin is massively unhelpful.

[@GouthamR013]

Parth can you do a video on "tensors" in feild equations?? 💗💗