Particle Physics 1: Introduction

[@mikestoneadfjgs]

I have been utilizing this channel for many months now in an attempt to better understand the universe around me and I HAVE to say that is the greatest source of information i have ever encountered in regards to truly understand the formalism behind the some of greatest milestones in physics. Im eternally grateful. Thank you.

[@kjpmi]

I agree with you. I'm doing the same. It's a cool feeling when you puzzle a concept out for a while and suddenly it clicks and you all of a sudden "get it." Since I was a little kid I have questioned everything. No explanation was every really good enough lol. It's amazing watching these videos and actually getting a pretty good understanding of the fundamentals of reality INSTEAD of the pretty poor dumbed down explanations one usually gets.

[@ahmettekin1616]

Geronimo Cornplante

[@joekaufman1874]

agreed!

[@AL-jg8pv]

lolz

[@Yatukih_001]

Jupiter he´s just trying to tell us how small an antifa´s brain is.

[@RudolfKlusal]

This is the greatest "non-proffesional" lecture to particle physics I have ever seen. Great work!

[@ZeroG]

Seems quite professional to me.

[@AkamiChannel]

I think he’s a professor at Nottingham University. Brady, who is behind the Periodic Videos channel also has a channel on physics and you can see this guy explaining stuff (same voice)

[@Quantum-]

@@AkamiChannel this isn't the same guy you're thinking of. This guy's name is Bob Eagle. He's not a professor. He's actually a radio host, singer, contributor to the field of physics. Just a jack of all trades, really. He just happens to sound a lot like Dr Mike.

[@heavennoes]

@@Quantum- I thought he had a doctorate in nuclear physics at king college?

[@Quantum-]

@@heavennoes he does. But he's not a professor. He is more like Brian Mays (I think that's his name) from queen. He has a PhD and has published papers, etc. But has pursued several different career opportunities outside of physics.

[@DrPhysicsA]

I'm really just trying to illustrate the principles here without getting too bogged down in the maths. You could argue that we are talking about a particle having a particular value of K such that K is zero for all values apart from the specific value associated with the particle.

[@UrbanChaos30]

This stuff is ridiculously simple. You're a very good teacher.

[@rileystewart9165]

Don't shrink his head's wavelength.

[@channagirijagadish1201]

Clearly, one of the best lectures on Particle Physics. Before taking a course on physics, it is best to start here to get the foundations right. Thanks, DrPhysicsA

[@DrPhysicsA]

Best route to become theoretical physicist, get initial degree and post-graduate degree and then seek a university research post.

[@STDrepository]

What if we just want to learn about particle physics for fun?

[@DrPhysicsA]

Silas Panelo Sadia Like most things, the jobs are highly competitive.

[@STDrepository]

Silas Panelo Sadia But I don't want to be a theoretical physicist.

[@blakops000007]

well i think a better way is after you gaduate you take courses in advanced mathmatics and modern mathmatical theorems it can really help you put your thoughts in equasions

[@billchristie5644]

DrPhysicsA I agree. My story is weird. I loved physics and architecture - like to draw and resolve. I encountered relativity and said I will never understand it intuitively. I explored the macro to micro sciences with analogies. Then in architecture I heard it for the first time - get outside the box - get uncomfortable - be aware of what you are dealing with. Suddenly the world was full of mystery and we have the power to look for the clues. I carried on with architecture, but that's when I realized that a rotating wave made up the electron (fermion) and explained relativity, etc inherently. Not de Broglie's pilot wave, but matter itself was a manifestation of the rotating wave. I'm a private entrepreneur and proud of it, but I will try to learn everything I can while I'm here. Going over these lectures is a great privilege. One must know the laws in detail in order to ask the right questions. Thanks so much. Bill Christie

[@trulucy]

Admittedly, I only completed high school and am now a middle-aged man here in the US and am familiar with basic math but I find learning about physics topics very interesting. This is the third video of yours I’ve watched so far and for me you explain these things very very well and I like that you write it all out and say it in plain terms. Wikipedia helps me a lot. Thanks for making these videos and I’m glad to be a new subscriber of yours in February 2019.

[@DrPhysicsA]

Jim Dogma has kindly responded. I'll just add that this is consequence of taking the derivative of an exponential. So d/dt of e^iwt = iw e^iwt

[@sihanchen1331]

Your pronunciation is charming! I love it !

[@ahmedayaz6685]

your lectures are simpler than leonard susskinds lectures great job Sir

[@gwho]

most definitely. I don't see why it has to be so complicated. Any concept can be made easier taught. Most people put up a hissy fuss when this is pointed out because usually they're not incentivized to put in the effort to research and refine their presentation. They can afford to put the onus on the student/customer citing laziness, shame, and ego. Those that do and can grasp it via the less intelligible way, don't complain, and in fact boast about it because it becomes a differentiating factor, they can hold it over others, and it's the accepted social climate aligned with the authority figure's preferences. I say fuck that I'll compete teach better, and reward those who do the same in the free market.

[@universalsailor]

gwho You are absolutely right about this. In fact, the situation is worse. Many science academics deliberately treat their subjects as repositories of holy writ to which they have been admitted but which must not admit others. They conceive their job as gatekeepers rather than popularizers , as if passing knowledge on will in some way lessen their own kudos. Typically, they try to mystify the material as much as possibl and talk in impenetrable jargon to help them do this, so we all know who's playing that game. These people should be flagged up, denounced and disincentivized ASAP. And all praise to guys like DrPhysics for going the exact opposite. He is a great teacher, with all the right instincts and a very amicable manner. If anyone should get an OBE it's him.

[@gwho]

intentionally obfuscate it, or refuse to teach it simpler, supposedly to filter people out. I mean, i get the Flynn effect is there too, but it's not the only way.

[@globaldigitaldirectsubsidi4493]

susskind is harder, more compressed, it is just a higher level and not for beginners.

[@waynelast1685]

Global Digital Direct Subsidiarity Democracy yes and no. Some of the subjects are a bit deeper but they are over complicated in my opinion.

[@capefear56]

Aspiring high school student here. Thanks a lot for the comprehensive introduction. Will be aiming to base my career in this extraordinary field.

[@petertravere5080]

i wish I had a tutor like this - HE IS GOOD!!!

[@DrPhysicsA]

Keep watching this series. It will appear in a later video.

[@Gismho]

And yet another EXCELLENT video. Thank you! You have a unique skill in lecturing/teaching. No wonder you've got hundreds of thousands of "views".

[@Dogboy73]

Very strange. I was watching a video on KZbin in bed. I eventually fell asleep & I guess when the video I was watching ended it somehow went into this one. I awoke in the early hours of the morning 45 minutes into part 2. I had a good couple of hours dream time physics lessons! Even stranger is that I remember the dream comprising entirely of this video's audio. The dream was visualized by a series of parallel washing lines running criss-cross. The washing lines were in rows of 10 & along each line ran a colored square (about 10 cm's across) that represented numbers & moved along in such a way as to illustrate calculations. Weirdest fucking dream I've had a for a long time!! Before going to bed I'd just completed a bottle of red wine. I went for a little lie down as I was feeling a bit worse for ware. 2 hours later I awoke from my dream completely & utterly perplexed but now with a firm grasp of particle physics. Amazing. I wonder what I will dream about tonight?!

[@dinomonaco2665]

Dogboy73 I

[@reddevil9554]

Well, as long as no-one's watching you, an interference pattern. :D

[@darrenbrad1721]

Yeah dont believe a word of that.nice story tho.maybe tonight you will dream up another fake story

[@darrenbrad1721]

Completed a bottle of wine. Really, completed. Hahahahahahahah

[@R0UTARAN]

This is just great! I'm a computer programmer and my math background is just introductory calculus (and that was a long time ago) but all of this stuff is still very easy to follow. I always wanted to have more detail, see a little more math behind the ideas presented by physicists in popular science talks and this stuff fits the bill perfectly. Thank you so much and please keep up the great work!

[@pankajnegi9795]

I cant thank you enough for these videos...they are really the best on youtube in the way you explain things.... hope you are doing okay and looking forward to new videos

[@Goodzboss]

Thank you so much DrPhysics. This is an amazing representation for some one like me [Who has an interest in GUT and particle physics, and general physics to boot] I have never had any opportunity to study this type of thing , so I do so in my own time.[ I dropped out of school thinking it wasnt getting me anywhere] now im 33 and have a keen interest on these topics. People like you help people like me realise thier dreams [and kick themselves for not pursuing university studies, when the opportunity was there]. If any one knows of some where online I can study/ learn particle physics [with a bit more detail, and at a pace I can work through] I would be very appreciative. Again DrPhysics the time and effort you have put into this video [first one of yours i found/ am yet to get to the others] is phenomenal. I really appreciate it

[@DrPhysicsA]

a- As an operator will take a basic state and annihilate it to create a vacuum. But if that state is in a high energy state then a- will simply reduce its energy state. Similarly a+ will create a basic state from the vacuum or increase the energy level if there is already a state there.

[@hidendiamond]

recently had my mind blown when i learned that, strictly speaking, "particles" are not really particles as one might normally envision them and "fields" are not really fields. i still plan to educate myself via your vids, but it is a strange new world for me having learned these things. very excited to have found the "Einstein Field Equations for beginners" vid. being able to push pause at anytime in order to think carefully about what is being said will enable me to get further with physics then if i was sitting in a lecture hall. thanks for the fascinating uploads DrPhysicsA!

[@miguelmouta]

This series is a prime of didactics and deepness, for the advanced concepts explained in rational sequence. I shared this video on facebook with my friends ( biomedical researchers in great part ) .Best wishes from Rio.

[@kelpdock8913]

incredible how much can be explained with a felt tip pen and voice

[@noracorbella1354]

OMG i recently found your channel and I love it! You explain everything so well.

[@andykopfleck]

Dr.Physics...Chapeau! Your channel conveys the profound knowledge of Natural Philosophy in a simple and efficient manner. Keep it up! :)

[@utkarshpande11]

hello professor. Thank you for the very lucid explanations of these concepts. Only the one who knows thoroughly can explain so easily. Einstein I think is supposed to ahve said "if the solution is very simple, god is answering". thanks sir.

[@mohammadharisfahim6614]

U r best. I am a physics lover who never made it to actually becoming a scientist. I salute your passion and effort. Keep it up.

[@hkhj139]

Great teacher! now physics seems really different after listening and watching your lectures... thank you so much may Allah bless you and your entire life and family sir! its such remarkable work you are doing for free... it's like talking classes in Oxford university!

[@Sena_608]

You are a wonderful teacher. I think I understand most of the content as a high school student. I will definitely watch all of your videos.

[@iconsumedmt1350]

I think I finally found a perfect channel to help me pursue physics

[@dijonstreak]

awesome. best yet. !! every dark cloud is going away and FINALLY seeing the gist of the whole matter...thanks to YOU. ..greatly appreciated.....!!

[@DrPhysicsA]

What exam board are you doing? What issues would you want covered?

[@ranjitsarkar3126]

I want the mathematics of string theory covered.

[@JimmyGray]

To whom it may concern. Because of teaching styles if you watch these videos on creation and annihilation operators and then watch professor Susskind's Stanford videos afterwards on introductory particle physics which also talks about the c and a operators they complement each other nicely. Block off 3 to 4 hours of time as i found it better to watch them both around same time.

[@DrPhysicsA]

Neither. This is simply saying that the more energy you borrow from the vacuum the quicker you have to repay it.

[@Shukla_1729]

DrPhysicsA who provide the energy to vacuum? At absolute zero vacuum has absolutely no energy.what is your opinion about QFT, QCD at absolute zero? Will it not breakdown? If it breakdown then how you are so sure about it correctness? Do you know non-relativistic schrodinger quantum mechanics is absolutely correct at any pressure and temperatue?

[@jaykemm3472]

Did this at a party last week. Huge hit. Thanks.

[@RagHelen]

This video is wonderful! It closes a the gaps I didn't understand in other introductions.

[@preeam108]

Great job man ! This is your first video that I am watching but guess I should get back to the QUANTUM MECHANICS ONCEPTS first. But really apreciate your efforts as I am a massive physics enthusiast. Keep up the good work, it is the efforts of passionate people like you that keep us physics enthusiasts' curiosity alive and breathing !!!

[@Unidentifying]

The photoelectric effect hypothesizes photons, in the double-slit experiment we observe the discrete points of light, hence particle-wave duality.

[@heribertobarahona7695]

I have studied a little of Quantum Mechanics before, but I found this video of you very good. You explain very well! I'll continue seeing this series of you and other ones too:)

[@rahulshaw8970]

at 01:04:05, there is a mistake. The psi terms are all summations over k, hence only the terms inside the summation comparison wont be sufficient and it should not be divided by k_square. Instead if you directly replace omega with k_square/2m, it would give the same result.

[@LaveenaMakhaik]

There is so much information on KZbin. You can literally learn anything if you want

[@physictist]

At 1:04:25 you divided the left side for -(i omega) because it is independent of k but I think dividing the right side for (ik)^2 is not ok at all because it has the sum over k (the sigma term). Can you explain it for me?

[@trfinl]

this was a mistake -- he should have changed the k^2 -> omega*2m inside the summation sign -- then all would have worked out OK. It seemed to work in the video, but as you noticed it was an accident because you can't just take the k factor outside the summation (or the omega for that matter).

[@MrOvipare]

This serves as a really smooth introduction to QFT! Thank you! I started to read a book about QFT but it got really overwhelming pretty quickly...

[@adamfattal9602]

"QFT for the Gifted Amateur" seems to be a relatively slow and steady one. Although you posted this 6 years ago so you probably got that covered lol

[@MisterBananaMan365]

Im just starting physics but I absolutely understand everything!!

[@heavennoes]

ik, I'm 10 and he is the only person / Ytuber the explains it properly!

[@Siralantoon]

Wow I almost understood some of that. Thank you so much for this delicious presentation; equations so sweet you can almost taste them. Yum!

[@tim40gabby25]

Wonderfully concise. Barely a word wasted.

[@antonsl-y5696]

Hello. Thank you very much for excellent videos! Quick question regarding the explanation at 13:24. If the cricket ball is moving at 100m/s, wouldnt the wave length be below the Planck length? And if so, wouldnt it imply that see the ball moving, so the movement which can be measured, but the wavelength is immeasurably small?

[@Urdatorn]

Oldie but goldie! Derivation of TDSE was brilliant.

[@rebokfleetfoot]

this is why theoretical physicists are either in school or retired. i thank goodness for them...

[@DrPhysicsA]

I use a panasonic SDR S26 camera mounted on a normal camera tripod and pointing vertically down.

[@Unidentifying]

It doesn't get rid of anything really. It just adds. Actually I think the double slit experiment is "THE proof" (as far as proof goes in science) for the wave-particle duality

[@alvarogarciazamarriego488]

You are the only God I believe in, sir. You are absolutely amazing. I wish I could ever have your intelligence. Thank you so much for these videos.

[@namrathagunnala4715]

You are so great you made me understand quantum field theory. Amazing! Keep doing what you're doing.

[@adamfattal468]

17:45 Are you just applying the Euler Formula to waves (and fields)?

[@pendalink]

This is awesome! However if you could tell me what video series I should start with to understand everything, that'd be great

[@DrPhysicsA]

Depends where you are at. Go to playlists page and start with playlist for GCSE. That's the basic level. Then do the A level playlist. More advanced. Everything else is pretty much uni level and you can do those in any order, tho best to do QM before Particle Physics.

[@pendalink]

thank you :)

[@DavidTJames-yq9dr]

I was really able to absorbe the vast majority of this. There are some formulas and effects that you speed thru and/or reference, but a bit of wikiGoogle'ing has covered those gaps. I am new to your series - breadcrumbing and reverse viewing as per your references - and look forward to rekindling my youthful love of math and physics at the atomic and quantum levels. Thank you so much for all this hard work and tsking the time to articulate. I believe I would have excelled better in my early academics had I found someone to explain these topics as you have. Consuming all of your vidoes will be my goal for this season. Cheers &much respects. Dave.

[@patrickmlavery]

AQA, the differences between types of errors, how to work them out and when to use them. Also just general investigative skills like significant figures, logarithms as a scale, rearranging common equations to the form y=mx +c, where to start and end a line of best fit with regards to a y-intercept, ie. does it need to go through the origin. Thanks

[@GeoffBernard]

At first I though you were calling him a hat :) After a little research, I now know it's meant to say "hat's off to you with respect." I came here to learn physics and end up learning language. Chapeau!

[@YoungColCol]

At around 53:30 you spoke about how fields can have different wave shapes. With sound waves, we can appreciate different timbres which depend on the wave shape of the sound. Are there similarly different 'timbres' of light?

[@moisepom]

great video. thank you for doing this. could you help us in understanding the basics of AdS/CFT correspondence principle ?

[@Jonosghost]

It's going to take me a few times to watch this before it makes good sense to me but it is mostly a pleasure to watch. Susskind is brilliant sure but so far I haven't seen him hit the white board like Dr Physics Alpha. For all \-/ the "Analysis" one may study, there exist -_~| differential geometry such that : general relativity makes sense. Should one learn analysis before attempting to understand quantum mechanics and what subjects should one be clear about before general relativity? Is it best to learn the concepts in the same order that they were chronologically published? Or are there finite examples such that : it is better to learn quantum mechanics before relativity is true?

[@coffeehawk]

Thanks for the great lecture...if only all professors taught their classes at this level...

[@DrPhysicsA]

eg the a- . You do indeed sum over all values of k. But since there is only one particle of a specific momentum k that is the one which is annihilated. All other values of a(k) achieve nothing.

[@TheShadow872]

Awesome channel, this is the best channel for physics.

[@nicouxgwendal]

Thanks for your answer. It will take some head scratching and some books reading before I fully understant it. But I have to say, particule physic is "passionnant" (yes I'm french) especially when explained the way you do in your videos.

[@sanjayraoshedge8924]

i am understanding it ,step by step ! please carry on !

[@Invaderzerg]

I would like to question the hypothesis that the electron orbits the nucleus similiarly to planets orbiting the sun. In that case I would like the velocity with which the electron orbits. According to some theories the electron can sort of "exist" in some regions around nucleus but not in others. I am refering to the electron probability clouds.

[@gibsonmaglasang]

Thank you very much, sir, for your passion in teaching these pieces of stuff! It immensely helped me in advancing my physics career and studies! Cheers!

[@anuragsikder3555]

Basically each photon interacts with an electron. If the photon provides enough energy to the electrons to overcome the work function then the electron is ejected from the metal surface and the rest of the energy which is left after overcoming the work function is then converted to Kinetic energy.

[@franktwinter]

Nice introduction! The only thing that confuses me is how at 1:04:00 you divide the fields by (ik)2 and (-i omega)? The 'k' is summed over (and so is omega) and therefor not present outside the summation

[@godzillazumagod9146]

Photon. How small is the black hole the sine wave of a wave 6X10^-35m in length. Frequence will sin perfact when v^2/r merges to an orbit at frequency. Thank you Drphysics.

[@teklemariamtessema7410]

Very interesting and can open eyes in sight of Particle physics

[@AkamiChannel]

15:20 why is it the circumference that matters rather than the area of the sphere?

[@nan9849]

What physical meaning the imaginary term isin(kx -wt) has in the expansion , e^i(kx - wt) -..........-(I)? The wave represented by (I) is a cosine wave only, right? Or the sine part has to do anything with this? I am extremely confused on what is the role of imaginary terms in waves as well as in Currents.

[@vincentvanravesteijn9592]

If the time evolution of a wave psi(x) would be written as: psi(x,t)=psi(x) cos(wt), then at certain times t the wave function would collapse completely and the particle would be gone (consider wt = pi/2, 3/2 pi, etc). Writing a wave like e^(iwt) would make sure that |psi(x,t)|^2 = |psi(x)|^2 at all times t.

[@musikpal]

@20:45, it's also prohibited by uncertainty principle.

[@13ooth_Ryan]

For the photoelectric effect at 6:32 I thought that if the energy wasn't the exact amount of energy it needed to move the electron to the next ionisation level the photon would just pass straight through it. Where as you've drawn it as if it absorbs the energy then emits it. ---If someone could get back to me to let me know if I'm wrong or something (and tell me why) it would be appreciated.

[@DrPhysicsA]

Ryan Booth Yes that is right. I hadn't got to that point yet.

[@13ooth_Ryan]

Oh rite, thanks

[@yonathanberuk2074]

I love this, thank you and please don't stop.

[@rebokfleetfoot]

it's very well done, thank you for all your works

[@cat-.-]

Question: Why cannot the electron in a sudden emit all its energy through radiation and fall directly through into the nucleus? That preserves the rule for the quantized energy level.

[@richardboland2897]

Does the annihilation operator act on the vacuum state to produce the anti-particle?

[@lugginstal5508]

Upfront: thanks a lot for your highly instructive letcures! I may address a problem that I have in the "Particle Physics 1: Introduction" at about 1:04:00, where you box the common terms in red color: you divide d^2(psi)/dx^2 by (ik)^2, where the latter is not common factor in the sum but the summation variable (which value of k of the sum do you divide by?). Thanks in advance!

[@dipikadash5573]

Really a good video to correlate mathematics physically. I want to ask a question. What makes an excitation in the field, so that a particle is getting generated? What is the cause of field excitation? Please reply me. Thank you for your nice explanation.

[@bhargavmanohar507]

At 33:40 you said the energy is borrowed for a short time even if the energy never existed, is the other way around possible? i.e. can the time be borrowed at the cost of energy?

[@jasonsvedin2259]

Question for you, if there is a "virtual" photon between two electrons communicating the force between them, but photons are quantized, does that mean that the strength of electromagnetic force is also quantized? I was under the impression that it changed continuously as the distance between two charged particles changed continuously.

[@fllev4121]

Thanks for the lecture! Weird that it has only garnered ~1% of likes, when most other presentations are usually at an average of 10% of likes. Must be that most people are afraid of thinking of the physical world from an analytical frame of mind or maybe they think that to "get physics" they have to get it from the "Tree of Knowledge ..."

[@fredericschneider5319]

Maybe I didn't get it or overheard it but why does the waveformed trjactory of an electron orbit in the nucleus have to "close"? I know that this results in the quantization of momentum of the electron so I'm interested to know why the trajectory visits one point in space around the nucleus each time around.

[@normusdoar]

This has to do with theory of waves. it says that the only posible way for a wave to not be destroied it must be stationary. or, you can imagine this: the electrons wave interacts with itself and the condition not to be destroid is when the wave/s is a multiple of the distance(electrons circle). to better understand,take a look at the interference pattern in double slit experiment.

[@natepepin09]

This really helps explain the integer values in those equations.

[@JustDiploid]

So... if I set up a big grating and fire cricket balls at it, they will impact a background screen with an interference pattern showing bands on the order of 6x10^-35m big? That's too small to measure, of course, but am I correct in principle?

[@dr.vannostrand411]

how is it that you just "create" a+ and a- ? Is there any sort of logical progression from H=1/2(p+iwx)(p-iwx) to a+ and a-? Or is it sufficient to say that a+ and a- are what they are because the commutator happens to be -1 when a+ and a- are given by those equations?

[@stefanotrezzi1096]

Very well-made video, but I didn't really understand how starting from the calculation of the partial derivatives of the field annihilation operator and them putting them all in one equation we got to the time-dependent Schrodinger equation. I mean what's the exact connection between these two things? I'd be really grateful if you could explain this to me DrPhysicsA.

[@scottnorman408]

What is the difference between a Photon and a Virtual Photon? Thanks

[@marcofsw]

13:32 The particle/wave "duality" is often misunderstood. This idea should be described as "QM objects behaves in a way the they sometimes appear to be waves and sometimes to be particles. However they are neither, these labels are macroscopic. Moreover, macroscopic objects does not behave in this (dual) way. Macroscopic objects have identity as opposed to QM objects." Many other macroscopic concepts have no meaning in QM, for instance "trajectory" and "collision/impact".

[@edgrood]

At about 1:04 you are equating the time and space derivatives of the wave function by dividing out terms involving w and k. However, these terms are inside summations and both depend on the summation index k. What is the justification for this step? Thanks.

[@cicciobomba4381]

in QMC 7 |phi> is the ket with lower energy, it isn't |n>.

[@rileystewart9165]

Does each type of quark have it's own field? What about different colored quarks? I'm assuming it's just 1 or 6 fields, more likely 6.

[@Miho-hl9yx]

sir, your videos helps me very much on my studies on quantum mechanics!! thanks so much!

[@pbfred1]

I have been trying to make a You Tube video of my Microscopic Theory and I would like to do it with paper and pen as you do. I bought a Logitech web camera and a stand to direct the camera onto my table and it just did not work. Could your direct me how I can purchase a camera and set up similar to yours. Peter Fred

[@SimpleScienceProductions]

Welcome to SimpleScience! Our very new Educational KZbin Channel. On here you will get to cover all sorts of science topics ranging from Biology, to Chemistry and to Physics in SIMPLE and SHORT and EXTREMELY INFORMATIVE videos from our experts! Please come and watch our channel!

[@QuantumBeef]

+DrPhysicsA 57:31 - how did you conclude that psi-dagger was 'sum a+ ...' . I've watched the QM concepts vids and took notes but can't remember going over this. This stuff is far ahead of my current physics knowledge but I'm seeming to follow the vids quite well, i can do the maths I'm just not sure how you got an equation for psi-dagger and also psi(x) [the second one]. Thanks!

[@life42theuniverse]

45:23 if the a+ operator acts on the a+|0> field and creates a particle in the first energy state, would the a-|0> operator create an anti-particle in the first energy level?

[@life42theuniverse]

52:00 Just seven minutes I would have had the answer. a-|0> = (0)^0.5 |(0) -1 >

[@UditDey]

@ 56:49, you replace the α(k) term with the a+(k) term in order to make it a quantum operator. But why? Is it just a "hit-and- miss"? Do we use it because it works, or is there reasoning? And by the way, awesome video!