Big up to MIT for offering these OCW lectures. I have learned Calculus, Classic Physics, Linear and Abstract Algebra, and Quantum Physics and I didn't even have to pay late library book fees. 👍🏾 Thanks MIT, for being conscientious and gracious! 🎉💥🪅🎇🤸🏽♂️🕺🏿💃🏼🎆🎊🙏🏾
Fell asleep watching a ghost hunting video, woke up and this was on my TV thanks to autoplay. I didn't even feel groggy waking up because I was so alarmed by how good of a teacher this guy is. I'm more of a molecular biology person but I think I'll continue watching these!
First you need to find it though. If you haven't figured out the value of science and scientific institutions yet you might end up "learning" "quantum mechanics" from "what the bleep" or Deepak Chopra, instead of learning it from MIT. The truth seems to be, that for many people it's hard to get on the right track without some type of guidance. They'll get sidetracked by conspiracy theories, fraudulent claims and various pseudo-sciences. And that may be understandable, since we haven't evolved to perceive or understand reality accurately. Furthermore our success (as a species) seems to be largely based on an accumulation of knowledge i.e. learning from other people and building upon that. So it's understandable that people can not see the value of the scientific method or scientific institutions. Scientific thinking isn't something, that has come naturally to us. It's not something that people just come up with themselves. So for most people it requires a person, who introduces them to science, leads them into the right direction, makes them ask the right questions etc. If you lack that you might not be very likely to end up here.
@@stauffap 4 years after my comment I'm not really any further with this lecture series. But started multiple other lectures on different topics like Human Behavioural Biology from Stanford. I'm also thinking of finally trythe problem sets, but I guess I maybe would be hit by a wall then. So I probably gonna try it anyways.
@@AlexTrusk91 You should definately try problem sets. You never fully understand physics if you can't do the math (you might just have the illusion that you understand it). I meet people all the time, who think that they understand a certain topic in physics, because they have developped a more or less accurate intuition, but they fail when confronted with having to calculate something and often fail as well with their intution. The ultimate test to whether or not you understand a certain topic in physics is always doing problem sets that involve math (and preferably understanding the derivations).
@@stauffap And can you help me abt problem sets like from where and how i should start to solve them like pre requisites and everything , i would really appreciate it
Six years ago, after I retired, I went through these lectures and the second semester with Dr. Zwiebach. Simply outstanding. I am back for a bit of review. Thanks Dr. Adams and Dr. Zwiebach.
I've seen a few other lectures from the other teachers and I didn't like them as much as these ones. I think this is a gem, and we should appreciate we can watch the best of the best for free. It's not limited to the 100 of the smartest hardworking kids anymore and it's awesome!
This is better though. All the learning with none of the crippling loans, egotistical teachers, or crushing deadlines! Einstein figured out SR while working as a patent clerk (though he did have a decent undergrad education)
You are my favorite teacher. I watched these lectures for the first time about four years ago. Because of these lectures, I have a very good understanding of basic quantum mechanics. I just completed my post-graduation from IIT Guwahati recently. These lectures were very helpful during the last four years.
I'm never going to directly use any of this but that hasn't kept me from trying to just understand it for my own curiosity. Never know when something will appear at the edges of something else and come in handy. This dude has come the closest so far to getting me there 🤣
I love this so much. Trying to decide on Electrical Engineering or Physics. Did a long stint with the Marines and now using G.I. bill at a wonderful community college for freshman year. I have not been in school for a long time lol. MIT is still a dream and it feels SO good to be able to just listen. Watching these videos let's me know that I AM smart enough to sit here, even if life may not allow it right now. To be able to touch my mind to something I have wanted since I was a child is a gift and I wanted to say thank you to MIT and Prof Adams for doing this. One day, even if I am retired, I will take a degree at MIT , so stay awesome!!!!
I was the kid at school who said I wanted to be a Physicist when I grow up... (... grow up.... something I might get round to one day ;-) and got told, "there's no point we already know everything" by the _teacher_ I went on to do mechanical and computer engineering with Physics /QM as the stuff I do for fun. but its more just a love of learning stuff do what you enjoy
I love the way the teacher brings those abstract postulates to live. In so doing he makes quantum mechanics crystal clear. He does it so well that one can not help feeling that there can't be a better way to put it (and I have thought about it several times). This work is invaluable! Just brilliant.
MIT is a very prestigious university. Very low acceptance rate because they take the cream of the crop in student's. If they do that for their students you can only imagine how they select their professors.
@@Ne012 yeah but : I went to Cambridge.. very selective on students.. terrible lecturing and teaching in general in the subject I studied which was economics.
I have my class 11 English language exam tomorrow, and here I am at 10 pm learning about wave functions,(this lecture is amazing and addictive though).
Absolutely in awe at what Dr. Adams can do with just whiteboard and chalk. In another life perhaps I'd be in that classroom, or better yet in another world, following the Many Worlds interpretation of this beautiful subject.
These lectures were very helpful in turning my room into a physics laboratory as I attempt to re-create the Hitachi experiment using homebrewed CRTs. It was not, however, all that helpful in subsiding my extreme existential terror. I'm going to be seeing things that go through neither both holes, nor one of the holes, nor none of the holes in my nightmares now. Thanks a lot, guys.
I studied Telecommunications engineering. And now I realized that I was not that far to be studying formulas to be applied to Quantum mechanics. I mean, all these mathematical functions of waves are almost the same. Of course it helps that I was reading and watching lots of videos about the "double slit experiment" and such, to know what are you talking about. But I never expected I would understand so much about Mathematics of the Quantum Mechanics. It is all about Waves.... This concept of uncertainty (given by waves) is driving me crazy (in a good way) This is the first Quantum Mechanics Lesson that I can "somehow" follow! Thank You!! Amazing Professor!!!
{X,P}= complete knowledge. Postulate 1: Wave function. Postulate 2: The wave function is a kind of 'generator function' of the probability that the particle actually be in certain x position. 26:30 Postulate 3: The states of the system are closed under linear combinations. Mathematica package. Fourier transform.
MIT is the only great source of quality education which is accessible to all.Thanks really i am greatly thankful to mit for giving the world a opportunity to become capable.
9:32 When he realizes how long we've been working on quantum theory he looks like a father proud of his son's progress. If I weren't dedicated to applying physics in the more esoteric corners of computer engineering that moment alone would have pushed me into pure physics.
It's amazing how accurate certain aspects of quantum mechanics can be calculated. They're basically just determining odds and they still get the right answer based on experiment. Weird.
You guys are too awesome. I finally start understanding quantum mechanics. I am a mathematician, chemist and aerospace engineer, but not a physicist. It is particularly hard to explain quantum mechanics to me, but you are outstanding. Will write my PhD thesis in quantum chemistry, which means that I can't have enough of quantum mechanics.
Ken, that's an odd statement. Obviously, in context, he is stating that a level of comprehension has personally been reached by him with enough confidence to state he is 'understanding' the current level of knowledge we hold. Obviously he isn't stating he's reached a mastery level of understanding that entirely exceeds that of all humankind to date... that would be a large assertion indeed.
your lecture is captivating, dear Allan! especially about superposition concept, i always just notice to math rule, but it has interesting physical meaning.
I'm somewhere in Kenya, and learnt about quantum computers, and I was curious. so I came across this lecture, and if i dont understand something I google it.. then i get another angle of understanding. i walk out of my house and look at the people and my relatives, i tell them about the beauty of quantum mechanics, and they just look at me like, do you have anything else to talk about, I'm like quantum computers will redefine the world as we know it... i'm just trying to understand where all this is coming from, how did they build that thing, what is the theory about it, what materials are used, where do they get them, how do they figure out the temperatures, how do they achieve that, how do they operate the thing.... well i guess it starts here, or somewhere close to here... so I'll keep on watching, going away to process everything, then come again the next day for more. this is heaven on earth!!!!!!!
This was one of my professors at MIT a while back. The class was exremely hard. He was a genius of course. . He talked pretty fast when teaching. . If for any reason you got behind , it was almost impossible to catch up.
I had quantum physics classes in 2018 taught by some brilliant nutter who couldn't teach a class to save his life... Smart but just terrible. What a great time it was
Some favorites: "Schrodinger's Cat, Wanted Dead And Alive" "Heisenberg Might Have Slept Here." And my own awful addition: "Mathematicians consider it risque when infinities cancel. Physicists are more tolerant. They do not mind if it happens during energy jumps as long as it is discrete!" Thumb this up if it is not completely horrible. My humor might have to be renormalized!
Nachiketa Ramesh Here is one not directly related to quantum physics, but reasonably funny none the less: "Entropy---It may not be the first bad law to keep a good man down but it is definitely the Second!"
Nachiketa Ramesh Well, you know, it ruins the perfect closed system. No perpetual motion machines. I guess if I have to explain it, the humor misses. Should I try again?
At 9:30 he just realized how crazy this science is at what he is teaching and the enormous exponential Research and knowledge we gain and how fast we went from X to y in such a small space of time
I think he has add or ADHD cause I am the same when I look and notice what's Ian saying " I'am like dude whaooooo are your even realizing what you're saying"
Really cool lecture! I am from germany and go to University here, but your Profs seems really excited to teach and he makes fun jokes, its so easy to listen to him :)
@1:00:12 Localized particles have less localized momentum because the momenta of the composite waves are cancelling and interfering with each other. Likewise, applying energy to the particles packet of waves causes the particle to move, albeit with some uncertain probability as to the direction/speed of movement. This movement reduces the coherence of the particle, and we become less certain as to where it is located. What is being described is the movement of a particle through space, but only if the particle is a secondary reaction created by the interfering waves. Try to imagine the amount of waves (EM or otherwise) passing through us at any second. Now imagine these waves all form the standing particles that make us up. They are highly localized, and their individual momenta are uncertain. But when we apply a macro-force to the system, the momenta of all these particles becomes more certain, and they become less coherent in the static, localized positions they were in before. As the waves re-settle, they regroup, becoming coherent again with all the particles being reformed in a different place and once again, localized.
Prof.John Admis, I couldn't express my thanks for your awesome lecture. Wave fns / Fourier series and transform notes. Also you're ready to any questions. Thanks :) for all things
Thanks Prof. Adams; absolutely brilliant intro into QM (not that I would know, I'm EE :-)). But just in case viewers need a perhaps equally well-taught lecture series on Fourier: There's an excellent treatment on this topic by Brad Osgood from Stanford available on YT. Highly recommendend!
Ugh as someone with a math degree, I have paaaain imagining the problem he just casually tossed out: show why the wave function must be continuous. THANK GOD it's just in one dimension as well.
Students can see other boards and digest the material in their speed. Videos presented here shows only the current positions of events; not pedagogically best practice. But lecturer is awesome. Thanks.
+Peter Jones Well, you can pause, which a student can't do. Seeing the board you are taking notes from getting rolled behind another one is especially frustrating, if I could pause in the actual lecture room, it would be very nice. Being able to follow MIT lectures from home AND be able to pause to take notes properly is close to divine to me
this question seems like some quiz appears in the English test, the listening part. And I forgot the answer when I see the question as I always did, lol!
Dr. Benedict Gross from Harvard stated in his Abstract Algebra lectures that you could never know enough linear algebra. Seems like the big point of the decomposition of wave functions into their linear combinations and superposition helps to illustrate both of their points.
@@charliecooper7458 Oh hey man, thank you. Let me make clear I am not a physicist. I'm actually an electrical engineer by training, and ever since graduate school 35 years ago I've just been really interested in physics and truly enjoy trying to help other people understand it. Alongside that, I have a few positions that aren't what you'd call "mainstream" (most re: consciousness), but I try to point those out if I mention them on Quora. Thanks for the kind words - I hope you have a great weekend. Stay safe and well!
Yeah, the first lecture is covering an intuitive understanding and developing a platform before introducing the mathematics. However, you can only progress so far before introducing that portion is required. However, MIT OCW has the prereqs on their site I'm sure.
@Eric R, try the second lesson again! We, who are watching here on youtube, aren't MIT students. I can sware, that mathematics (esp. calculus) has been taught to us for centuries as it was an enemy. We need to fight for better teaching!! Those Professors must work on this!! They must try their very best, and I think most of them will fail (as I can see in regular schools) - but, this is not an excuse for giving up this demand to the Universities!!! Let's continue asking for what we need. Giving up is not an option.
Assuming you understand calculus I used WolframAlpha for my PC, I have it because I knew it was a good math package and it was real cheap in Windows store, it relies on a backend server though and I crashed it entering a complex addition of several waves. Then enter the equations he blows over like (e^0.2it) or (e^2it) and see the results real and imaginary and the sin/cos breakdown. You can also enter the normal and normal square to see that |e^2it| or |e^2it|^2. His lecture would be helped if he had a math package on his PC and ran samples of the equations he wrote up there through a math package, shown on the overhead projector. The days of memorizing heavy or even light math are over, using the same math through a package long enough the memorization will occur eventually.
@@mykofreder1682 I do not believe something like 'understanding calculus', still trying to learn Lagrange formalism. I think, this is something to 'go through' - which means "shut up, follow, and calculate!". But: your advice "WolframAlpha" was a surprise, although it's not hidden (and never was)... In a school, we have to do more than I can oversee. Will try to get closer. Reflections welcome! :)
There's something I don't understand: I've learned that quantum wave functions can be described as a "ket vector" in an abstract vector space called Hilbert space. The position wave function, for example, used to express the probability of finding the particle at a point, can be described as a vector in an infinite dimensional Hilbert space. But we also have the wave function used to describe spin ("spinor"), and this wave function exists in a 2-dimensional Hilbert space. So my question is, what is the relationship between these two different wave functions? I've also heard that the wave function contains everything that there is to know about the particle, but I'm like, "which wave function 😭😧?" I would be really thankful if someone could help!
The spatial wave function in the Schrodinger picture, psi, is not the same as a ket vector, | psi >. psi is the projection of |psi> onto the position basis: psi = < x | psi > | psi > holds all the information of the general quantum state and can be projected onto different basis's. That's why it's so useful. For example the momentum wave function can be arrived at by projecting | psi > onto the momentum basis: psi = < p | psi > But if you had just psi, the 'wave function', you still have a full picture of the quantum state because you can go to the ket | psi > from it.
@@paulryan94 Thank you for your answer, but the question I asked above was answered on physics stack exchange right after I made my comment. So it's no longer something that confuses me :). Here's the link to the question and answer on the site, if you're interested: physics.stackexchange.com/questions/560132/wave-function-as-a-ket-vector-in-a-hilbert-space
At 32:23 he says that the momentum of the particle for the given wavefunction is p = (h_bar)(wave number) = h/(wavelength of the wavefunction) but shouldn't its momentum be h/(wavelength of the particle).Are (wavelength of the wavefunction) and (wavelength of the particle) the same thing and what does (wavelength of the wavefunction) mean?
There are no particles in quantum mechanics. That's just the worst misnomer in all of physics. There are quanta. Quanta are combinations of energy, momentum, angular momentum and charge (electric charge, lepton number etc.). These system properties get exchanged from one system to another. Take a system with one charge, massive quantum, i.e. an electron. That's about as complicated a system as we can describe with this level of quantum mechanics. A single electron, on detection, gives us only one energy and momentum value. Imagine therefor an infinite repetition of that electron. That's called a quantum mechanical ensemble. The wave function of the quantum mechanical ensemble for one defined energy and momentum value can be described by a plane wave and that ABSTRACT plane wave has a wavelength. We can recover this wavelength in scattering experiments (many electrons scattering on a crystal lattice, for instance) physically. For a single electron that wavelength is not defined. Why? Because a single quantum doesn't give us an energy/momentum spectrum. We can't predict from just one measurement what the next measurement will give us. In order to measure that spectrum we need many quanta.
The thing I love about quantum mechanics is just how damn hard it is to understand. If you think you are clever and you don't understand quantum mechanics then there are a lot of people far more intelligent than yourself. I don't understand it and my intelligence is put into perspective by perhaps the most difficult subject in the world.
IMO, a "quantum vibrational wave/ripple" is set off at the point where the electron is fired. A quantum aerodynamics of sorts. The wave precedes the electron. It is this wave that is responsible for the distribution pattern as each electron, even though fired 1 at a time, is carried on it. It explains the "probability" of where each would land. When you try to measure the electron, it is not the "conscious" act of doing it that causes the electrons to behave as particles, but it's because you break the wave. Thus, as there is no wave for the electron to ride on, it will come through the slit as an independent particle.
No, not really. Mathematicians develop math based on the depth of results that can be achieved. L_inf and L_2 spaces allow really deep results (most of which physicists don't care about).
When I was in high school and first heard Einstein’s equation I thought he was talking about turning objects into pure energy via accelerating them to the speed of light. Getting it’s total energy.
Now that RUclips provides an overlay graph of the most watched parts of the videos when you hover the mouse over the timeline, I find it pleasing that that graph has two peaks, a smaller peak at 6:25 and a larger peak at 36:37. Remind you of anything? =)
So basically what we learn here is that all charged particles create a transverse electrical wave in the ether medium defined by the COS function, and the particles also create a magnetic wave in the ether that is orthogonal, and 90 out of phase, and lagging the electric transverse wave. The magnetic field is defined by the SIN function. The probability of find the particle inside the wave it creates in the ether medium is defined by COS^2 + SIN^2 of the electrical and magnetic fields (or a superposition of feilds) it creates as it travels through the fluid ether or magnetic field. Also we learn that quantum works only when the fields we superpose are caused by individual particles and not just waves, because there have to be individual momentum associated with each wave. So we can get a general wave caused by the different particles and superpose them, but the momentum of each wave doesn't not superpose well. We also learn the polarizers are just radiators of the light signals they receive and when we put a polarizer at 45 degree angle to two quarter wave polarizers they can retransmit a light signal back into the original direction of travel of the light. The ether medium creates a double layer around all prisms from which we can extract a evanescent wave, with another prism or polarizer. So the polarizer at 45 degrees doesn't transmit all of the signal orthogonal to the original direction of travel and the next polarizer can pick up that signal and transmit it through as light. ruclips.net/video/9BkfFjr9Tyw/видео.html
he's referring to the group class held by the other professor, not the previous lecture. A group class is more like the classes you have at high school level and lower, in that you do problems and ask questions and sometimes they go through things on the blackboard. Edit: they might be using a different system than what I am used to, but I am at least fairly certain that he was talking about something similar.
1:17:00 I think the Geiger counter messed with the camera and microphone for a second based off the angle of that plate while you were reading it. Cool!
So what he's trying to say is that as far as the double slit experiments are concerned, it's not that the particle is interfering with itself, it's that the two natures of the particle (wave + particle) are interfering with themselves. Got it.
At 39:02 Man, I was so excited to see that the postulate that covers everything about quantum mechanics was "FREE PIZZA". One cannot begin to imagine the disappointment that that was not the case :'(
He's all right. I teach wave functions in a similar way, however more advanced. I like to ask my students questions as I'm moving forward. I like to feel them out and I enjoy the interaction. We professors all have our own styles.
Big up to MIT for offering these OCW lectures. I have learned Calculus, Classic Physics, Linear and Abstract Algebra, and Quantum Physics and I didn't even have to pay late library book fees. 👍🏾 Thanks MIT, for being conscientious and gracious! 🎉💥🪅🎇🤸🏽♂️🕺🏿💃🏼🎆🎊🙏🏾
Amazing !
Fell asleep watching a ghost hunting video, woke up and this was on my TV thanks to autoplay. I didn't even feel groggy waking up because I was so alarmed by how good of a teacher this guy is. I'm more of a molecular biology person but I think I'll continue watching these!
I love watching him lecture! He's so excited to show everyone "here's everything we've figured out so far, come help us figure out more!"
Whoever filmed this did a great job. Panning and framing. Spot on.
Would have been nice to see his laptop screen as direct instead of through the projector... still, a wonderful job as you said.
@@scowell wow wow, we're not talking about THAT much advanced technology here.
A class that ends with an applause. That is how all classes should be.
Not at all! Only professors with good didacts as this one deserve applauses!
i think this kind of high quality content makes the world a better place for seekers.
First you need to find it though. If you haven't figured out the value of science and scientific institutions yet you might end up "learning" "quantum mechanics" from "what the bleep" or Deepak Chopra, instead of learning it from MIT.
The truth seems to be, that for many people it's hard to get on the right track without some type of guidance. They'll get sidetracked by conspiracy theories, fraudulent claims and various pseudo-sciences. And that may be understandable, since we haven't evolved to perceive or understand reality accurately. Furthermore our success (as a species) seems to be largely based on an accumulation of knowledge i.e. learning from other people and building upon that. So it's understandable that people can not see the value of the scientific method or scientific institutions. Scientific thinking isn't something, that has come naturally to us. It's not something that people just come up with themselves. So for most people it requires a person, who introduces them to science, leads them into the right direction, makes them ask the right questions etc. If you lack that you might not be very likely to end up here.
You obviously missed this: 53:13. Think about it.
@@stauffap 4 years after my comment I'm not really any further with this lecture series. But started multiple other lectures on different topics like Human Behavioural Biology from Stanford.
I'm also thinking of finally trythe problem sets, but I guess I maybe would be hit by a wall then. So I probably gonna try it anyways.
@@AlexTrusk91
You should definately try problem sets. You never fully understand physics if you can't do the math (you might just have the illusion that you understand it).
I meet people all the time, who think that they understand a certain topic in physics, because they have developped a more or less accurate intuition, but they fail when confronted with having to calculate something and often fail as well with their intution. The ultimate test to whether or not you understand a certain topic in physics is always doing problem sets that involve math (and preferably understanding the derivations).
@@stauffap And can you help me abt problem sets like from where and how i should start to solve them like pre requisites and everything , i would really appreciate it
Six years ago, after I retired, I went through these lectures and the second semester with Dr. Zwiebach. Simply outstanding. I am back for a bit of review. Thanks Dr. Adams and Dr. Zwiebach.
;Touch and hold a clip to pin it. Unpinned clips will be deleted after 1 hour.😢hh
O❤
❤❤❤
Teaching in MIT is like a superstar singing on stage. Everyone claps for the good performance.. Holy moly
People get excited when I stop speaking too, probably for a different reason
I wish I took school more seriously as a kid so I could go to this school. This professor is amazing and I love his passion.
So do I.
Yeah, you can learn now.
I've seen a few other lectures from the other teachers and I didn't like them as much as these ones.
I think this is a gem, and we should appreciate we can watch the best of the best for free.
It's not limited to the 100 of the smartest hardworking kids anymore and it's awesome!
This is better though. All the learning with none of the crippling loans, egotistical teachers, or crushing deadlines! Einstein figured out SR while working as a patent clerk (though he did have a decent undergrad education)
You can always work harder now.
You are my favorite teacher. I watched these lectures for the first time about four years ago. Because of these lectures, I have a very good understanding of basic quantum mechanics. I just completed my post-graduation from IIT Guwahati recently. These lectures were very helpful during the last four years.
Truth be told, your IIT professors must learn pedagogy from these professors.
@itchy armpits I majored in physics.
Engineering Physics?
I'm never going to directly use any of this but that hasn't kept me from trying to just understand it for my own curiosity. Never know when something will appear at the edges of something else and come in handy.
This dude has come the closest so far to getting me there 🤣
love this guys passion
An absolutely perfect lecturer
I love this so much. Trying to decide on Electrical Engineering or Physics. Did a long stint with the Marines and now using G.I. bill at a wonderful community college for freshman year. I have not been in school for a long time lol. MIT is still a dream and it feels SO good to be able to just listen. Watching these videos let's me know that I AM smart enough to sit here, even if life may not allow it right now. To be able to touch my mind to something I have wanted since I was a child is a gift and I wanted to say thank you to MIT and Prof Adams for doing this. One day, even if I am retired, I will take a degree at MIT , so stay awesome!!!!
i did bachelors in electrical engineering now i am going to switch to masters in physics!
How is it all going ?
I was the kid at school who said I wanted to be a Physicist when I grow up...
(... grow up.... something I might get round to one day ;-)
and got told, "there's no point we already know everything" by the _teacher_
I went on to do mechanical and computer engineering with Physics /QM as the stuff I do for fun.
but its more just a love of learning stuff
do what you enjoy
I love the way the teacher brings those abstract postulates to live. In so doing he makes quantum mechanics crystal clear. He does it so well that one can not help feeling that there can't be a better way to put it (and I have thought about it several times). This work is invaluable! Just brilliant.
Oh my goood, how can this be so much better than at my university?? The whole structure and order in which this is taught are just so clear!!
MIT is a very prestigious university. Very low acceptance rate because they take the cream of the crop in student's. If they do that for their students you can only imagine how they select their professors.
@@Ne012 yeah but : I went to Cambridge.. very selective on students.. terrible lecturing and teaching in general in the subject I studied which was economics.
They put him in camera for a reason. I imagine they have good and bad professors also
I have my class 11 English language exam tomorrow, and here I am at 10 pm learning about wave functions,(this lecture is amazing and addictive though).
Absolutely in awe at what Dr. Adams can do with just whiteboard and chalk. In another life perhaps I'd be in that classroom, or better yet in another world, following the Many Worlds interpretation of this beautiful subject.
I wish there was a RUclips channel with instructors who are obviously super interested in the topic they are teaching regardless of the subject
These lectures were very helpful in turning my room into a physics laboratory as I attempt to re-create the Hitachi experiment using homebrewed CRTs. It was not, however, all that helpful in subsiding my extreme existential terror. I'm going to be seeing things that go through neither both holes, nor one of the holes, nor none of the holes in my nightmares now. Thanks a lot, guys.
Here, kid, have a cookie. :-)
I studied Telecommunications engineering. And now I realized that I was not that far to be studying formulas to be applied to Quantum mechanics. I mean, all these mathematical functions of waves are almost the same.
Of course it helps that I was reading and watching lots of videos about the "double slit experiment" and such, to know what are you talking about. But I never expected I would understand so much about Mathematics of the Quantum Mechanics.
It is all about Waves.... This concept of uncertainty (given by waves) is driving me crazy (in a good way)
This is the first Quantum Mechanics Lesson that I can "somehow" follow!
Thank You!! Amazing Professor!!!
Physicists always try to use the same math, it was the kind of math especially designed for them.
The concepts are easier to understand when you know the language, like psi and B*B
{X,P}= complete knowledge.
Postulate 1: Wave function.
Postulate 2: The wave function is a kind of 'generator function' of the probability that the particle actually be in certain x position.
26:30
Postulate 3: The states of the system are closed under linear combinations.
Mathematica package.
Fourier transform.
MIT is the only great source of quality education which is accessible to all.Thanks really i am greatly thankful to mit for giving the world a opportunity to become capable.
This is the best TV show I've ever watched
9:32 When he realizes how long we've been working on quantum theory he looks like a father proud of his son's progress. If I weren't dedicated to applying physics in the more esoteric corners of computer engineering that moment alone would have pushed me into pure physics.
High school senior here, I'm actually fascinated with that EXACT field!
Came to his first lecture thanks to 3B1B, and here I am intending to go through as much as I can from Allan Adams ❣
In which video did he refer to allan?
It's amazing how accurate certain aspects of quantum mechanics can be calculated. They're basically just determining odds and they still get the right answer based on experiment. Weird.
Let me sound smart and say that is empirical knowledge 😌
In his mind the epic depth of what he is teaching is the objective gospel. Flight of the Valkyries... Passionate dude.
Man, I love this lecturer! He's so enthusiastic!
You guys are too awesome. I finally start understanding quantum mechanics. I am a mathematician, chemist and aerospace engineer, but not a physicist. It is particularly hard to explain quantum mechanics to me, but you are outstanding. Will write my PhD thesis in quantum chemistry, which means that I can't have enough of quantum mechanics.
Ken, that's an odd statement. Obviously, in context, he is stating that a level of comprehension has personally been reached by him with enough confidence to state he is 'understanding' the current level of knowledge we hold. Obviously he isn't stating he's reached a mastery level of understanding that entirely exceeds that of all humankind to date... that would be a large assertion indeed.
Quantum chemistry sounds awesome!
Lies again? WTF WOF
I liked the StrongBad reference at 40:02 :) very subtle.
play ride of the Valkyrie when he asks for it, fits beautifully.
The teacher and course lecture is awesome, very professional. excellent job
your lecture is captivating, dear Allan! especially about superposition concept, i always just notice to math rule, but it has interesting physical meaning.
Watching these for fun. What a great professor!
same. its completely irrelevant to my school work but its just so damn interesting
Watching before 1 day of exams
SOMMAN EDU did you pass? Are you now a quantum theorist
@@financewithsom485 how did they go
@@roku6194i am a software engineer now studied mechanical engineering that time this comment is 4 years back 😂
Great lecture. Can't wait for the free pizza at 5!
LMAO!!! xD
Dang. I missed it by 3 years...
The pizza is an imaginary component probably
@@NovaWarrior77 - I missed it by 4.
Wait it said free pizza at 5, not at 120…?
I'm somewhere in Kenya, and learnt about quantum computers, and I was curious. so I came across this lecture, and if i dont understand something I google it.. then i get another angle of understanding. i walk out of my house and look at the people and my relatives, i tell them about the beauty of quantum mechanics, and they just look at me like, do you have anything else to talk about, I'm like quantum computers will redefine the world as we know it... i'm just trying to understand where all this is coming from, how did they build that thing, what is the theory about it, what materials are used, where do they get them, how do they figure out the temperatures, how do they achieve that, how do they operate the thing.... well i guess it starts here, or somewhere close to here... so I'll keep on watching, going away to process everything, then come again the next day for more. this is heaven on earth!!!!!!!
This is the one subject that still holds my attention.
This was one of my professors at MIT a while back. The class was exremely hard. He was a genius of course. .
He talked pretty fast when teaching. . If for any reason you got behind , it was almost impossible to catch up.
Did you graduate?
58:54 VERY slick teachable moment here. THIS shows that this guy knows his shit and gives a damn that the students can see how things connect.
This guy is good! A lot better than any of the physics classes I took!
I had quantum physics classes in 2018 taught by some brilliant nutter who couldn't teach a class to save his life... Smart but just terrible. What a great time it was
Some favorites:
"Schrodinger's Cat, Wanted Dead And Alive"
"Heisenberg Might Have Slept Here."
And my own awful addition:
"Mathematicians consider it risque when infinities cancel. Physicists are more tolerant. They do not mind if it happens during energy jumps as long as it is discrete!"
Thumb this up if it is not completely horrible. My humor might have to be renormalized!
This is awesome!
Nachiketa Ramesh Here is one not directly related to quantum physics, but reasonably funny none the less:
"Entropy---It may not be the first bad law to keep a good man down but it is definitely the Second!"
CHistrue I didn't get this one. Second law of thermodynamics right? What man? How did it keep him down X(
Nachiketa Ramesh Well, you know, it ruins the perfect closed system. No perpetual motion machines. I guess if I have to explain it, the humor misses.
Should I try again?
CHistrue Yes please!!
11:54 "Happy electrons" this guy is the Bob Ross of Quantum
At 9:30 he just realized how crazy this science is at what he is teaching and the enormous exponential Research and knowledge we gain and how fast we went from X to y in such a small space of time
I think he has add or ADHD cause I am the same when I look and notice what's Ian saying " I'am like dude whaooooo are your even realizing what you're saying"
Really cool lecture! I am from germany and go to University here, but your Profs seems really excited to teach and he makes fun jokes, its so easy to listen to him :)
I study at a Fachhochschule and yet I'm here watching these videos instead
I paused the video and started Ride of the Valkyries for the III postulate. Definitely added something to it.
So thankful now of all the hard work I put into Fourier series and transforms and convolution that I can do these problem sets.
@1:00:12
Localized particles have less localized momentum because the momenta of the composite waves are cancelling and interfering with each other. Likewise, applying energy to the particles packet of waves causes the particle to move, albeit with some uncertain probability as to the direction/speed of movement. This movement reduces the coherence of the particle, and we become less certain as to where it is located. What is being described is the movement of a particle through space, but only if the particle is a secondary reaction created by the interfering waves.
Try to imagine the amount of waves (EM or otherwise) passing through us at any second. Now imagine these waves all form the standing particles that make us up. They are highly localized, and their individual momenta are uncertain. But when we apply a macro-force to the system, the momenta of all these particles becomes more certain, and they become less coherent in the static, localized positions they were in before. As the waves re-settle, they regroup, becoming coherent again with all the particles being reformed in a different place and once again, localized.
proved to be a major help in understanding the uncertainty principle : )
but how can you be sure?
Prof.John Admis, I couldn't express my thanks for your awesome lecture. Wave fns / Fourier series and transform notes. Also you're ready to any questions. Thanks :) for all things
Thanks Prof. Adams; absolutely brilliant intro into QM (not that I would know, I'm EE :-)). But just in case viewers need a perhaps equally well-taught lecture series on Fourier: There's an excellent treatment on this topic by Brad Osgood from Stanford available on YT. Highly recommendend!
20 years ago I had these same types of classes. No clue what was going on at the time. Now I get it. Maybe can go get that A I was looking for!
1:17:08 - I love how happy he is as he says "It's got uranium in it!"
When the Prof. rubs the chalk off the black board, doesn't it go into his open coffee bottle?
Chalk is nontoxic when consumed in moderation.
@@grandpaobvious Yes, may be Calcium in it is even beneficial for the bones!
if youre paying attention...the chalk is already in the coffee bottle, and also not in the coffee bottle
There is.probably a function to assess that
Welp that settles it, I definitely wanna be a physics major
No Name Sharma Really?
Yes! This was so cool :-)
+dubhad Physics major here - actually, there is a 1% unemployment amongst physics majors, unlike the 49% among business majors.
+Joseph Godoy that's probably because 99% of physics majors don't want a job.
+ahadicow No, quite the opposite. The 99% do have jobs, either in mathematics, physics, or sometimes on wall street or in business.
Really love the content available on youtube.
Ugh as someone with a math degree, I have paaaain imagining the problem he just casually tossed out: show why the wave function must be continuous. THANK GOD it's just in one dimension as well.
Here I am. Looking forward to an hour long lecture on the Wave Function.
Did you learn something?
Students can see other boards and digest the material in their speed. Videos presented here shows only the current positions of events; not pedagogically best practice. But lecturer is awesome. Thanks.
+Peter Jones Well, you can pause, which a student can't do. Seeing the board you are taking notes from getting rolled behind another one is especially frustrating, if I could pause in the actual lecture room, it would be very nice.
Being able to follow MIT lectures from home AND be able to pause to take notes properly is close to divine to me
What does his wife call his signature?
a wave function
Are you sure? I think he started something on the lines of My wife calls it a little gift ... ?
this question seems like some quiz appears in the English test, the listening part. And I forgot the answer when I see the question as I always did, lol!
Yeah it's clearly edited out for some reason.
Rubbish
Quantum physicist pickup line: your wave function is so beautiful.
Really amazing
Thank you all so very much.
Exactly 40:00 - a very subtle homestar runner reference.
Very great professor, very interesting way to teach
Dr. Benedict Gross from Harvard stated in his Abstract Algebra lectures that you could never know enough linear algebra.
Seems like the big point of the decomposition of wave functions into their linear combinations and superposition helps to illustrate both of their points.
I 100% approve of the emphasis on dimensional analysis.
IVE SEEN YOUR COMMENTS ON QUORA, You’re awesome!!
@@charliecooper7458 Oh hey man, thank you. Let me make clear I am not a physicist. I'm actually an electrical engineer by training, and ever since graduate school 35 years ago I've just been really interested in physics and truly enjoy trying to help other people understand it. Alongside that, I have a few positions that aren't what you'd call "mainstream" (most re: consciousness), but I try to point those out if I mention them on Quora.
Thanks for the kind words - I hope you have a great weekend. Stay safe and well!
Are the recitation videos available? Thanks
I followed the first episode 100%. Then I plummeted :(
Yeah, the first lecture is covering an intuitive understanding and developing a platform before introducing the mathematics. However, you can only progress so far before introducing that portion is required. However, MIT OCW has the prereqs on their site I'm sure.
@Eric R, try the second lesson again! We, who are watching here on youtube, aren't MIT students. I can sware, that mathematics (esp. calculus) has been taught to us for centuries as it was an enemy. We need to fight for better teaching!! Those Professors must work on this!! They must try their very best, and I think most of them will fail (as I can see in regular schools) - but, this is not an excuse for giving up this demand to the Universities!!! Let's continue asking for what we need. Giving up is not an option.
Assuming you understand calculus I used WolframAlpha for my PC, I have it because I knew it was a good math package and it was real cheap in Windows store, it relies on a backend server though and I crashed it entering a complex addition of several waves. Then enter the equations he blows over like (e^0.2it) or (e^2it) and see the results real and imaginary and the sin/cos breakdown. You can also enter the normal and normal square to see that |e^2it| or |e^2it|^2. His lecture would be helped if he had a math package on his PC and ran samples of the equations he wrote up there through a math package, shown on the overhead projector. The days of memorizing heavy or even light math are over, using the same math through a package long enough the memorization will occur eventually.
@@mykofreder1682 I do not believe something like 'understanding calculus', still trying to learn Lagrange formalism. I think, this is something to 'go through' - which means "shut up, follow, and calculate!". But: your advice "WolframAlpha" was a surprise, although it's not hidden (and never was)... In a school, we have to do more than I can oversee. Will try to get closer. Reflections welcome! :)
@@JaredBryan calc and linear algebrah strongly recommended
This man is so funny .
Creativity is intelligence having fun in motion right here .
There's something I don't understand: I've learned that quantum wave functions can be described as a "ket vector" in an abstract vector space called Hilbert space. The position wave function, for example, used to express the probability of finding the particle at a point, can be described as a vector in an infinite dimensional Hilbert space. But we also have the wave function used to describe spin ("spinor"), and this wave function exists in a 2-dimensional Hilbert space. So my question is, what is the relationship between these two different wave functions? I've also heard that the wave function contains everything that there is to know about the particle, but I'm like, "which wave function 😭😧?" I would be really thankful if someone could help!
The spatial wave function in the Schrodinger picture, psi, is not the same as a ket vector, | psi >. psi is the projection of |psi> onto the position basis:
psi = < x | psi >
| psi > holds all the information of the general quantum state and can be projected onto different basis's. That's why it's so useful. For example the momentum wave function can be arrived at by projecting | psi > onto the momentum basis:
psi = < p | psi >
But if you had just psi, the 'wave function', you still have a full picture of the quantum state because you can go to the ket | psi > from it.
@@paulryan94 Thank you for your answer, but the question I asked above was answered on physics stack exchange right after I made my comment. So it's no longer something that confuses me :). Here's the link to the question and answer on the site, if you're interested:
physics.stackexchange.com/questions/560132/wave-function-as-a-ket-vector-in-a-hilbert-space
38:30 "This is what quantum mechanics is all about"
*pulls down board and shows "Free Pizza"*
At 32:23 he says that the momentum of the particle for the given wavefunction is p = (h_bar)(wave number) = h/(wavelength of the wavefunction) but shouldn't its momentum be h/(wavelength of the particle).Are (wavelength of the wavefunction) and (wavelength of the particle) the same thing and what does (wavelength of the wavefunction) mean?
There are no particles in quantum mechanics. That's just the worst misnomer in all of physics. There are quanta. Quanta are combinations of energy, momentum, angular momentum and charge (electric charge, lepton number etc.). These system properties get exchanged from one system to another. Take a system with one charge, massive quantum, i.e. an electron. That's about as complicated a system as we can describe with this level of quantum mechanics. A single electron, on detection, gives us only one energy and momentum value. Imagine therefor an infinite repetition of that electron. That's called a quantum mechanical ensemble. The wave function of the quantum mechanical ensemble for one defined energy and momentum value can be described by a plane wave and that ABSTRACT plane wave has a wavelength. We can recover this wavelength in scattering experiments (many electrons scattering on a crystal lattice, for instance) physically. For a single electron that wavelength is not defined. Why? Because a single quantum doesn't give us an energy/momentum spectrum. We can't predict from just one measurement what the next measurement will give us. In order to measure that spectrum we need many quanta.
when the wavefunction is your signature
Find someone who protects you like the Prof protects the superposition formulas on the chalkboard
Wow, they applauded for the guy. Well deserved.
The thing I love about quantum mechanics is just how damn hard it is to understand.
If you think you are clever and you don't understand quantum mechanics then there are a lot of people far more intelligent than yourself.
I don't understand it and my intelligence is put into perspective by perhaps the most difficult subject in the world.
41:33 both sides of the equation are superposition in gravitational contraction
IMO, a "quantum vibrational wave/ripple" is set off at the point where the electron is fired. A quantum aerodynamics of sorts. The wave precedes the electron. It is this wave that is responsible for the distribution pattern as each electron, even though fired 1 at a time, is carried on it. It explains the "probability" of where each would land.
When you try to measure the electron, it is not the "conscious" act of doing it that causes the electrons to behave as particles, but it's because you break the wave. Thus, as there is no wave for the electron to ride on, it will come through the slit as an independent particle.
So this is why we spent so much time talking about L2 spaces in functional analysis!
No, not really. Mathematicians develop math based on the depth of results that can be achieved. L_inf and L_2 spaces allow really deep results (most of which physicists don't care about).
When I was in high school and first heard Einstein’s equation I thought he was talking about turning objects into pure energy via accelerating them to the speed of light. Getting it’s total energy.
2 years from now I'll be sitting in that class...
1 more year!
covid-19 goes brrrrrrrr
@@deepserket4390 😂😂😂
One of the best Professors
Now that RUclips provides an overlay graph of the most watched parts of the videos when you hover the mouse over the timeline, I find it pleasing that that graph has two peaks, a smaller peak at 6:25 and a larger peak at 36:37. Remind you of anything? =)
43:00, 51:00, 1:00:00 (why are we uncertain about the momentum?), 1:02:00 amplitude !!, 1:12:00 fourier analysis…
We aren't uncertain about momentum. Momentum is locally conserved.
So basically what we learn here is that all charged particles create a transverse electrical wave in the ether medium defined by the COS function, and the particles also create a magnetic wave in the ether that is orthogonal, and 90 out of phase, and lagging the electric transverse wave. The magnetic field is defined by the SIN function.
The probability of find the particle inside the wave it creates in the ether medium is defined by COS^2 + SIN^2 of the electrical and magnetic fields (or a superposition of feilds) it creates as it travels through the fluid ether or magnetic field. Also we learn that quantum works only when the fields we superpose are caused by individual particles and not just waves, because there have to be individual momentum associated with each wave. So we can get a general wave caused by the different particles and superpose them, but the momentum of each wave doesn't not superpose well.
We also learn the polarizers are just radiators of the light signals they receive and when we put a polarizer at 45 degree angle to two quarter wave polarizers they can retransmit a light signal back into the original direction of travel of the light. The ether medium creates a double layer around all prisms from which we can extract a evanescent wave, with another prism or polarizer. So the polarizer at 45 degrees doesn't transmit all of the signal orthogonal to the original direction of travel and the next polarizer can pick up that signal and transmit it through as light. ruclips.net/video/9BkfFjr9Tyw/видео.html
Basically 😂
Why I'm feeling that this lecture is not in continuation with lecture 2 ,since in lecture 2 he didn't discuss polarization !
he's referring to the group class held by the other professor, not the previous lecture. A group class is more like the classes you have at high school level and lower, in that you do problems and ask questions and sometimes they go through things on the blackboard.
Edit: they might be using a different system than what I am used to, but I am at least fairly certain that he was talking about something similar.
Anurag Pradhan from Miami
Polarization was just an analogy of how the box discussion.
1:17:00
I think the Geiger counter messed with the camera and microphone for a second based off the angle of that plate while you were reading it.
Cool!
8.04.1 = Look at me, I'm watching an MIT quantum physics class and I *get this*
8.04.3 = *head exploding*
I understand here in sir here till the 2019 and I had seen there 1 million subscription now it's 2.5 approx I'm quite happy
We think of ourselves as more solid and separate in the universe than science reveals us to be.
They even have the assignments available, this is all I ever dreamt to have at my mexican university
Thanks this was really helpful for my grade 11th Quantum mechanics chapter 😀
So what he's trying to say is that as far as the double slit experiments are concerned, it's not that the particle is interfering with itself, it's that the two natures of the particle (wave + particle) are interfering with themselves. Got it.
At 39:02 Man, I was so excited to see that the postulate that covers everything about quantum mechanics was "FREE PIZZA". One cannot begin to imagine the disappointment that that was not the case :'(
i didnt go to sleep listening to mit quantom physics but i woke up listening to mit quantom physics
Great thanks for letting us know that lectures
Good Dr., are you implying light is simultaneously part, particle. beam, as well chunk?
No. ;-)
amazing lecture
I knew the physics had been altered as soon as the words particulars were used.
what rabbit hole did i go down when i was sleeping
He's all right. I teach wave functions in a similar way, however more advanced. I like to ask my students questions as I'm moving forward. I like to feel them out and I enjoy the interaction. We professors all have our own styles.
intense
How many flies are you teaching in your studio apartment? ;-)