Quantum Physics: BOSONS and FERMIONS Explained for Beginners

Here's how Quantum Physics predicts the existence of Bosons and Fermions - but we also discuss what those words even mean!
Hey everyone! I'm back with a new video, filmed a few weeks before we hit 50k subscribers! Thanks so much for all your support. In this video, I wanted to talk to you about two different kinds of particles, known as Bosons and Fermions. You may have heard of these two classes of particle. For example, a few years ago the Higgs Boson was in the news a lot. This, naturally, is a kind of boson. And you may have heard of a particular kind of fermion known as the electron.
Well the existence of bosons and fermions is predicted by quantum mechanics, if we consider a simple system consisting of two (or more) indistinguishable particles. These particles in our system are not only identical in every way (same mass, same charge, etc.), but they are indistinguishable from each other. This means we cannot label them as particle A, particle B, etc., and track them over time. If we leave our system alone for a while and then come back to it, then we have no way of knowing which particle is which. All we know is that the number of particles in the system beforehand is equal to the number of particles in the system afterwards.
This assumption that our system consists of indistinguishable particles can actually be encoded mathematically. If our particles are to be indistinguishable, then we can imagine labelling them particle A and particle B. But this is only for the purposes of our own calculations. If the particles are really to be indistinguishable, then our system must look the same regardless of whether we have particle A on the left and particle B on the right, or if the two particles have swapped positions - we must have no way of knowing. And if that is the case, then the probability distribution of our system (the probability of finding two particles in two given locations in space) must be the same regardless of whether we have particle A on the left and B on the right, or if they are swapped around. I've made videos in the past about indistinguishable particles, so please do check them out on my channel.
As we see in the video, the probability distribution of our system is very closely linked to the wave function of our system. Specifically, it's linked to the square of the wave function. And so we can equate the squares of the wave functions for a scenario where we have particle A on the left and B on the right, and when they are swapped around.
When we do this, we can then follow some simple mathematics to tell us that for a system like this, we can see two different kinds of wave functions. One where the wave function is unchanged when the two particles are swapped, and the other where the wave function becomes negative when the two particles are swapped. These are two different classes of particle. The system of particles that has its wave function unchanged when particles are exchanged, is known to contain bosons. The system that has its wave function become negative under particle exchange is known to contain fermions.
As it turns out, we have seen many particles that display either bosonic or fermionic behaviour. Bosons can display special behaviours such as Bose-Einstein condensation, while Fermions must obey the Pauli Exclusion Principle. I will make videos about both of these topics in the future, so keep an eye out for them.
Until then, I hope you enjoyed this video. If you did, please leave a thumbs up and subscribe, and head over to my second channel "Parth G's Shenanigans" (here / @_parthmusic ) for some of my original music! Follow me on Instagram @parthvlogs.

[@ParthGChannel]

Hi friends, thank you so much for your support! I've just made a video discussing SPIN very generally - check it out here: kzbin.info/www/bejne/enTVp5Skd5eIjaM :)

[@moriyartyholmes3914]

Still unable to understand, why u have so less subscribers. The quality and the knowledge in your videos is outstanding. Best of luck brother you are doing great job. Keep it up..👍👍👍 hope u'll have million subscribers Very soon.

[@mmessick]

Great video!

[@SkotoSbyBishoP]

So, if matter is Fermions, why is it that when we approach 0K it behaves as a Bose-Einstein condensate? I'm clearly misunderstanding something, and I'm struggling to find out an explanation. I'd be obliged if you could answer my question! Your videos are amazing, keep it up.

[@Arseniy_Afanasyev]

@@SkotoSbyBishoP 2 fermions can behave like 1 boson. to be precise, they are not equivalent in zone but have some properties of motion characteristic of a photon. True, I am not very good at how it works at such a formal level. More intuitive explanation: the nuclei of the crystal are attracted to the passing electron and "suck in" the next electron. Therefore, they travel as a whole - this is the Cooper pair.

[@Arseniy_Afanasyev]

Hi! Nice video) How is the spin of a particle related to the sign of the wave function? PS please Like this comment to receive a reply notification

[@markosullivan6444]

Absolutely fascinating! I've never seen bosons and fermions distinguished in this way before; it made so much sense!

[@ParthGChannel]

Thanks! Glad you enjoyed the video :D

[@dippy9119]

I feel this is the clearest possible explanation of bosons and fermions that can possibly exist. But I still don't get it.

[@GeovaniLopesDias]

As I get it, the particles' names are like naming the different solutions to the wave function. As we do detect, testing the conditions/solutions the theory proposed us, the particles with this or that behavior, we can say that those particles do exist or not. In another words, the math that describes how fields do behavior (like waves) can point us the way to do physics. In the Parth's example, he just distinguish two particular particles.

[@PewPew_McPewster]

The way I try and internalize it is, there are two broad ways of categorizing subatomic particles that make it very easy to predict the distribution of energies of those particles in your systems. Bosons, because of what they are, follow the Bose-Einstein distribution, and we see this exact distribution of energies from the light spectrum of our sun- the proportion of all photons that have energy E will be easily predicted under the Bose-Einstein distribution, allowing us to engineer a lot of shenanigans like solar cells since we can account for this. On the other hand, fermions can be described in a similar way using the Fermi-Dirac distribution. The most immediate use is to describe how electron energy levels are formed, and tells us useful things like why semiconductors can conduct at room temperature but not as absolute 0- because this distribution "smears" at higher temperatures, predicting that some electrons will be energetic enough to exist in the conduction band. So they are essentially two tools for us to describe and predict the probability that particle p has energy E, depending on what kind of particle p is: boson? Or fermion?

[@PewPew_McPewster]

I just went through material that he didn't cover in the video, but I think it's useful to try and keep in mind a more practical picture of bosons and fermions as we discuss them at this level of abstraction. Quantum mechanics is very beautiful in that all these layers of abstraction play into each other in such and intricate way.

[@DarkMatterVisible]

It's really not, this was actually a quite poor explanation. I'm not even sure I would call it an explanation of bosons and fermions at all.

[@prathyushaoleti284]

This is the first time i've heard a clear explanation of bosons and fermions ,thank you so much.

[@ankitaseth8033]

I really wish had found someone like you during my school's days who would've made me fall in love with physics

[@paul4105]

Your explanations in quantum physics really impresses me, I specifically like how you described quantum tunneling in your other video. Definitely earned a sub !

[@user-zn3el8pl9j]

அருமை அண்ணா! எனக்கு ஆங்கிலம் நன்றாக தெறியும் எனக் கூற வியலாது! ஆனால் உங்களது விடயம் புரிதலை ஏற்படுத்துகிறது! 🙏🏾💐💐💐

[@gargigole1461]

Best explaination ever.This is the video I was searching for long time.

[@dougieh9676]

Love you Parth. I love quantum physics too. Keep up the great videos. ☮️☮️☮️

[@hunkarun]

I suppose in essence bosons are related to "Force" and fermions are related to "Forms". Brilliant stuff!

[@MinaASamir]

Great video man, the first video I stumble upon from you, easy to understand and I like how you explain it, keep it up ❤️❤️❤️

[@vedantchimmalgi463]

very helpful was waiting for such a video

[@lchakrapani]

As always, a great explanation of the quantum model that forms the basis of all chemistry and the quantum model of the orbitals where electrons are found. Well done Parth!

[@thanushme9054]

OMG THANKS A LOTTTT!!! The way u explain all these is soooo easy to understanddd!!!

[@rc5989]

A very well outlined format for the scientific method applied to theoretical physics at 5:00 and a very well done video all around. Thanks Parth!

[@user-mu7oc3hq5f]

I just wanted to say that your videos help me so much, I have never really understood fermions and bosons this way before and I think after watching your video, I understood it a bit more

[@EricKolotyluk]

WOW - that was the best explanation of the difference between Bosons and Fermions I have ever seen... well done!

[@vishnurahul3378]

Crisp and clear explanation. Thank you for the video

[@stripeysoup]

I have a Masters in theoretical physics but I still enjoy coming back to some of your videos. The way you describe concepts gives an understanding that the purely mathematical cannot give.

[@dr.snpatro2714]

Hey stripey soup! Aahh i want a bot help can u help me regardimg physics .im a major enthusiast of it.

[@dr.snpatro2714]

Btw where are u from?

[@dr.snpatro2714]

And whats ur real name? Im nikhil patro from india!

[@ParthGChannel]

Hey thanks for the kind words!

[@kelly-iy5mz]

Hey I have a doubt..! If two particles are indistinguishable...how do you classify (know) that electrons swapped there position...and higs bosons didn't...how do you know electrons fall in fermions category,if you can't tell which electron is which..?? Similarly how do you know that higs boson didn't changed there position..and can be classified into Bosons category..

[@somakraychowdhury7524]

need different videos, explicitly for Bose-Einstein formula n the Fermi-Dirac one....this could be the next step for understanding...!

[@mohitverma8384]

Thank you so much Parth for such a beautiful explaination.

[@Chemistryuntold]

It was just awesome. Thank you for this simplified mathematics.

[@saras756]

Thank you! This video was very helpful, sorted out the confusion and questions that arose from my textbook! 😃

[@hunkarun]

Brilliant explanation. Succinct and comprehensible. THANKS!!!

[@depressedyouth]

I was aware of fermions of bosons before, but this video offered me a whole new perspective!

[@khushipatel1723]

keep up the good work ..really looking forward to see more of ur videos..👍

[@alex_8704]

An amazing explanation. Thank you.

[@Trixex]

this video is gold, you deserve more followers.

[@davidg3190]

I love this type of video. Understandable for everyone.

[@aishwaryasam5805]

LOVED THE VIDEO

[@yasir.3486]

Your videos just became more neat... Keep up the good work

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This Channel is an awesome new discovery for me!

[@remidanvin4057]

Very clear and concise

[@PrettyMuchPhysics]

Great video! Also really like the new font. However, for equations, it looks a bit off, I kinda prefer your handwriting in those places :p

[@ParthGChannel]

Hey thanks so much! Appreciate the feedback, I think you're definitely right :D In the next video I'll do all the equations by hand

[@cipherxen2]

Excellent video. Thank you so much.

[@davidwright8432]

Thanks, Parth! I've always been puzzled about how 'identical' and 'indistinguishable' are not the same. now I know!

[@joaquinbadillogranillo8252]

Supeeeer interesting and super simplified! I would really like if you could talk about the Euler-Lagrange differential equation and the principle of least action, you can really simplify things!

[@umeshchandramakwana806]

You are making every maths involved very simple making the physics very simple!

[@shayandeepbhaumik3369]

I came infront of this video just meadering in youtube and out of curiosity but surprisingly it helped me in one of my confusions as i was studying quantum physics for my coursework. Thanks a lot...Great content

[@GauravGupta-pb8mk]

Fantabulous Sir. Thank you.

[@pirismail9201]

Best explanation ever. love you.

[@PraveenKumar-pu4nz]

You are awesome at explaining bro 🙏🏼

[@masroorch2956]

I was searching for such kind of quality stuff on bosons and fermions for my exams ❤

[@SALESENGLISH2020]

You will be a great physicist someday. Thanks for explaining difficult things so simply.

[@onlyphysics143]

you decribed naturally and purely thank you sir. take care sir God bless you here and hereafter

[@saikumarreddyyeddula5043]

Quite nice, It's simple and precise

[@englishinenglish3473]

Breathtaking and astonishing , I haven't even thought they were discovered overed by such an easy math 🙃 Thank you , ya are the best professor

[@Garen1]

Amazing video, amazing explanation, amazing presentation

[@aparnam192]

I feel like spending my time watching your videos. I got a clear picture of this concept in 13. 55 min which I couldn't make it in reading the whole book and the derivations I have been learning day by day.

[@suhas4095]

This was an amazing video!! Thanks for doing it! Could you please make a video on why psi^2 gives us the probability!

[@amarparajuli692]

Wow! You just made my love for Physics return.

Thanks for clarification :)

[@evanr.lowetechgamingandcoo1410]

Great video.

[@merikijiya13]

You’re a great teacher.

[@mitulbhaiakbari5571]

You earned my like and I am already a subscriber

[@Wannabetolkien]

You are one of the best Bro..Thanks for the Video and Is there a chance that you make a video on Heat Flow?

[@vannanilavan1927]

Awesome video

[@sakshidwivedy1677]

Really love your videos... they're always fascinating... Plz make a video on quantum field theory ❣️

[@mayahammamouche8820]

Amazing video

[@illogicmath]

Excellent channel. You got a subscriber

[@dinghanxue704]

Hi Path, In one of your video you said that particle spin is a special relativistic effect in quantum mechanics. I’m very curious about that cause no other youtubers are willing to dive this deep into quantum physics. So I really hope you could make a video that elaborate on that point a little further. Thanks!

[@quahntasy]

*Love your videos and hey that hairstyle is epic*

[@ParthGChannel]

Hahah thank you, quarantine is bringing out some interesting hairstyles

[@SAHZ-xe3pz]

Your a great teacher , take care

[@zainkhalid5740]

Awesome!

[@learnlikechiu9783]

Thx, Your Video help me a lot

[@henriquemarra6565]

Love love love it

[@sarkaragha]

Great job. thank you. you occupy all the time half of the screen, while you can omit or reduce it in order to have more room for pictures.

[@rahulnundlall6524]

Your videos are amazing, they make these concepts appear simpler and actually give a good understanding. This is coming from a university student who has a course on QM. Btw , the maths is NOT easy!

[@reemibrahim4847]

You uploaded thank youuu

[@kaellum4260]

I'd love to hear you explain this on the basis of information or infons.

[@vnana2991]

Thanks!!!

[@nikhilpatro6376]

hey ur the best explainer of physics even then professors!!!

[@jcr723]

Love your videos. I was surprised you didn't go the next step and explain the Pauli Exclusion principle. That you could have a BE condensation can be understood by undergraduates (low enough temp and all particles go to lowest state). But its still unclear how anti-symmetric wave fcts give Pauli Exclusion principle

[@priyapatel6522]

Thank you

[@alwaysfunnobarriers.8674]

These comments prove the emptiness or unwillingness of the teachers to explain what they learned. Thank you very much sir. As I am able to understand the meaning of WAVE FUNCTION at the age of 51 . Thank you very much once again sir.

[@haitham3afef103]

Great! Please make a video about quantum statistical mechanics

[@johnsalkeld1088]

When you follow the full complex maths this is even more of a nice result

[@bewise952]

Bro I know this earlier but then to I watched cause your my fav

[@wilsongomes3360]

Very good.

[@Goldslate73]

Sir... We are gonna have words... The day we meet. Brilliant!

[@mahekdholu6243]

Jahpna tu shi great ho 🙏🙏😍

[@semmering1]

I always need to look video twice, it gets now slightly better ;-)

[@John-yj8zb]

Thanks Great!

[@accgurulegal4388]

You Are Awesome

[@seabeepirate]

Thanks for the simple explanation. Are other classes of particles predicted by mathematical symmetries?

[@nunushetmitiku4481]

You make it very easy and very helpful. with this kind of simple explanation, you can explain Einstein's field equations easily. next time explain Einstein's field equations because quantum physics and general relativity mix together to form the theory of everything.

[@rajdeepchavan9684]

Very useful video. Can you give examples of bosons and fermions??? How can we distinguish particles between fermions and bosons??

[@KD-ho5xk]

At the same time as explaining us about this cool stuff, are you also using the feynman technique for yourself?

[@shishirjha7744]

Parth, Very clear & very precise. You are doing great service to Physics community. Should be difficult for you, but could you please slow down the vocal speed a bit ?

[@rahusphere]

Why should he slow down, that's his natural tone. Maybe you should just concentrate more.

[@PewPew_McPewster]

When you realise that the statistics surrounding bosons and fermions are the reason why photovoltaics works the way it does, it's really quite transcendental. One describes the energies we get from the sun, the other describes how energetic the electrons in the solar cell are. Unfortunately when you combine them together, they tell you that your solar cell will never be more that ~33% efficient if there's only one absorber layer 😭

[@elizabethmeghana9614]

wowwwwww ........ i love your teaching , its amazing , it made so much sense , go ahead , if feynaman was alive , he would be proud of you :) ... love from india

[@priyankas2715]

Superb

[@shreyasmahamuni6951]

with every video, if possible, can you provide some links for good and short notes or any book?

[@shorobalamakash2250]

Your amazing man ..

[@ParthGChannel]

Thank you! :D

[@inboccaallupo14]

You are a pure genius. I can tell you can become as good as Richard Feynman or even better if you put enough effort into teaching physics.

[@sauravneogi7024]

This is too much

[@inboccaallupo14]

@@sauravneogi7024 Okay

[@johnpaulbounce3708]

Nice topic. I did not spend my 14 minutes (plus some couple of minutes in understanding the topic) for nothing. Looking forward for more videos like this.

[@ParthGChannel]

Thank you! :D

[@hp3262]

I'm liking the font. It's very neat

[@ParthGChannel]

Thanks very much! :D

[@vishalmishra3046]

Great video Parth. Here is a naive question. Wave functions are complex numbers and repeated experiments can measure probability distribution but how is the phase (argument) of the complex number determined by experimentalists, esp. the relative difference is significant such as between those of 2 particles in a quantum system. Thanks and love watching your videos.

[@kabhishek5668]

Brilliant Parth. Why don't you try explaining about Quantum Parallelism?

[@chandrasekhar-vi8se]

First of all thank you very much for explaining things in very simple manner. Please make a video on Einstein’s famous equation E=mc^2. Thank you 😊