MIT 8.04 Quantum Physics I, Spring 2016 View the complete course: ocw.mit.edu/8-04S16 Instructor: Barton Zwiebach License: Creative Commons BY-NC-SA More information at ocw.mit.edu/terms More courses at ocw.mit.edu
Пікірлер: 866
@BiscuitZombies4 жыл бұрын
This is brilliant. This professor explains things extremely clearly.
@BeckBeckGo4 жыл бұрын
Agreed totally. His pacing also is fantastic
@prototype81373 жыл бұрын
Lol.
@RobH.3 жыл бұрын
He is a pseudo scientist!
@tanishqbagria54593 жыл бұрын
I'm 12 and I got it too
@RisitasKEKW3 жыл бұрын
Does he tho ?
@luisangelespinozahumberth101611 ай бұрын
Que nivel de clase de este profesor . Orgullo peruano .
@elitedelobos11 ай бұрын
No es peruano es Judío Ultramar. Judío ...
@juanrodrigovalencia11 ай бұрын
@@elitedelobos Puede ser de origen judío, pero nació en Lima, creció y estudió en Lima, graduándose de la Universidad Nacional de Ingeniería. Es recontraperuano
@elitedelobos11 ай бұрын
@@juanrodrigovalencia No. El siempre la tuvo clara. Es un judío y tiene nacionalidad judía.
@juanrodrigovalencia11 ай бұрын
@@elitedelobos En serio? Y tiene pasaporte "judío"? Por favor JAJAJAJJAJA
@ginnopuma11 ай бұрын
@@elitedelobosmira mongol si Vienes a opinar sin info mejor ni opines lapiz😅
@marcocarrasco60379 ай бұрын
Barton, el único estudiante en la historia de la UNI que se graduó antes de terminar su carrera.
@moinmalik1320 Жыл бұрын
Besides the wonderful clarity in his lecture, I am amazed at his very clear, beautiful, and organized writing on the board.
@Thighwatts Жыл бұрын
A good university isn't just made by the sum of their students' success but by the ability of their professors to teach and simplistically explain complexity!
@user-nk4bj9gb4e26 күн бұрын
well this is universal fact
@mayimbu666211 ай бұрын
El mejor alumno de la historia de la UNI.
@ARCP-mj1mr10 ай бұрын
Es de mi facultad
@paultarazona798910 ай бұрын
@@ARCP-mj1mrq nunca lo ejerció
@joser.982710 ай бұрын
@@paultarazona7989XD
@omargclb10 ай бұрын
@@paultarazona7989😂😂
@cesarrolandorumichehernand26439 ай бұрын
Buena la profesión le sirvió para hacer investigación, dónde invierten otros países extranjeros.
@BSP201014 жыл бұрын
"It's a debacle! A total disaster!"
@keepgoing3353 жыл бұрын
there's something about writing on a chalkboard that just makes it much better than presentation slides as a teaching medium for showing equations
@pmo19725 жыл бұрын
"That's what polarizers do for a living" :)
@flossenking4 жыл бұрын
lol
@xtra-oi9xb4 жыл бұрын
.... what percentage of polarizers are unemployed .. that's what I wanna' know ... it seems the good professor overlooked this dilemma during the lecture ..... hmmm .....
@MikeSmith-cl4ix4 жыл бұрын
The polarizer proves that light is a wave and not a particle.
@MikeSmith-cl4ix4 жыл бұрын
@Phoenix do you think Trump is a real president?
@MikeSmith-cl4ix4 жыл бұрын
@Phoenix when the Suits come for you, don't answer the door.
@KipIngramАй бұрын
It's important to point out that when the polarizer is aligned at some "middle angle," then the light that comes out is NOT identical to the light that went in. Not only does only a fraction of the light come through, but that fraction now has polarization aligned with the POLARIZER, not aligned as it was going in. The polarizer "turns" the polarization angle so that the outgoing light is aligned with it. This raises the fascinating situation where you can put two polarizers at perpendicular angles together, and no light gets through. But if you then slip a third one in between the first two aligned at, say, 45 degrees, then suddenly some light does get through.
@petrok1rp2544 жыл бұрын
Such amazing job Mr. Zwiebach! Thank you...
@manaoharsam42113 жыл бұрын
Great Teacher. Takes time and explains well. Defined indeterminism very clearly.
@gregsg23513 жыл бұрын
This lecture has nothing to do with me but I became entranced with his style and voice! And I actually learned something new in quantum theories. Thank you Sir.
@pity47773 жыл бұрын
Well spoken with excellent handwriting. A rarity among physics professors
@vector83104 жыл бұрын
This exposition is as clear as can be
@milind-96834 жыл бұрын
thank you MIT, thank you sir, and thanks to whole staff there.
@mohammadasefhossaini79853 жыл бұрын
Thank you MIT and sir. Wish him long life and happiness.
@SatishSingh-mk7jq2 жыл бұрын
Thank You for making it understandable !! I am a software engineer in network domain. I just watched these videos(first 4) out of curiosity, and I was able to understand a rough picture of what's trying to be conveyed. Last time I studied physics was in pre-college days.
@andressuarez61534 ай бұрын
peruvian's proud!
@richardmakiya71883 ай бұрын
@@andressuarez6153 así es.
@ramonasosna7 ай бұрын
I definitely agree when you mentioned that it's good to learn from physicists and it's useful that we have them, it is good to make new explanations for what comes next.
@lesubtil76534 жыл бұрын
I can tell he is a good teacher because I understood this little "lecture" better as when my teacher taught me the same subject, even if my teacher spoke my first language (french), and this teacher speak english, that is harder to understand for me.
@rajinfootonchuriquen Жыл бұрын
In some sense, the fact that he is peruvian and has as first lenguage the spanish, it make him use simpler words to do his lectures so it's easy to follow him in his thoughts.
@RC-uo3ds3 жыл бұрын
Brilliant lecture given by Barton Zweibach Sir .....
@ralphdams75684 жыл бұрын
What a wonderful teacher you are, if I may say so. Thank you for sharing this lecture with the public. 🤓
@StarNumbers4 жыл бұрын
A shill can only repeat the obvious -- it's in the public.
@ralphdams75684 жыл бұрын
🙂
@eastwestcoastkid4 жыл бұрын
Bertrand de Born really?
@eastwestcoastkid4 жыл бұрын
Bertrand de Born I’m sorry MIT is one of the preeminent science and engineering schools on the planet. So this professor has earned his position in that esteemed University. Have a nice day. Also no one ridiculed anyone-I think you’re projecting-and I’ve learned quite a bit thank you much 😃😉
@eastwestcoastkid4 жыл бұрын
Bertrand de Born oh please-try this-why don’t you go to Feynman’s lectures in Physics and start reading at volume 3. You learned this in 9th grade huh? I doubt it. This is Quantum Physics-you did not learn this in 9th grade. Go to OCW, and look at the ENTIRE CLASS genius. Tell me, why do you have to use the renormalization group in Quantum Electrodynamics? How do you know you understand English? Fella, you lost all credibility when you questioned the status of MIT. All credibility. Have a nice day, remember not to go out as you don’t want to be exposed to SARS-Cov-2 and get COVID-19. There’s a good fellow. G’night 😉😃👍. Oh and we are done.
@Unambiguously1823 жыл бұрын
I really like his handwriting This looks so passionate
@Tensoren-yj9ux3 жыл бұрын
In that case I advise you to check out Nima Arkani-Hamed.
@apolloniuspergus92953 жыл бұрын
Well, the bell inequality just shows that you cannot have both a local and hidden variable theory combined. If you have a hidden variable theory, it has to be non-local, and if it's local, it has to not rely in hidden variables
@Krish_202 Жыл бұрын
Yeah pretty good argument 🤷♂️
@hansenchrisw Жыл бұрын
Thank you. Was about to make a similar comment. Bell himself was a proponent of Pilot Wave theory aka Bohmian mechanics. A completely deterministic, nonlocal, hidden variable theory.
@evcman43834 жыл бұрын
Man, I just enjoy listening to his voice....
@oussamaaljarroudi97243 жыл бұрын
Me tooo I swear to God 😄😄😄😄
@jessewallace12ableАй бұрын
I want everyone to pronounce photons as he does.
@user-ie2ur4ry5t11 ай бұрын
Good and clear teacher. Good tempo and very to the point.. Absolutely well done and definitely keep it up!!! .
@justinkane2902 ай бұрын
Wow, clearly explained and at a pace I can work with. Gonna be watching more of these.
@user-tt2po5wg7n5 ай бұрын
Well spoken with excellent handwriting. A rarity among physics professors. Maravilha de aula! Eu diria um pacote de fótons de aula! Parabéns!!.
@ryanrizzo38667 жыл бұрын
Thanks for the lectures!
@sgsmozart3 жыл бұрын
Wow !...A professor who writes cursively ! 🎊🎉🎊
@fjs11112 жыл бұрын
This professor is one of the best
@sell_or_stfu84054 жыл бұрын
Wow. The universe it truly random. Thank you.
@pellythirteen56546 жыл бұрын
Good and clear teacher. Good tempo and very to the point.
@Adityarm.083 жыл бұрын
These lectures are awesome!
@smalin4 жыл бұрын
What are all the physical processes (besides the behavior of polarized photons) that are non-deterministic? Is radioactive decay non-deterministic? Is there a complete list of non-deterministic processes somewhere? Are all non-deterministic processes somehow the same process at their core?
@eastwestcoastkid4 жыл бұрын
smalin yes as quantum mechanics describes radioactive decay-yes. Same process at their core? Only in the sense that they are part of the class of non-deterministic things. Ah the point behind quantum mechanics and quantum theory is that what we think as determined is at base, not deterministic.
@trafalgarla4 жыл бұрын
It's not an easy question to answer because what is deterministic (or whether anything is deterministic) depends on which interpretation of quantum mechanics is correct and we don't know which one is correct. For example, everything is deterministic in the Many Worlds interpretation, including radioactive decay, since the wave function describes all possible events. Questions about determinism are usually left to philosophers of physics nowadays so the Stanford encyclopedia of philosophy is a good starting point to read up on some of it. plato.stanford.edu/entries/determinism-causal/
@francoisdeletaille3 жыл бұрын
@@eastwestcoastkid In my view It is the instant (now) that determins reality, on the base of what is determined previously. So that the instant is not completely severaged. By this, I do not means that the instant acts upon reality, but that it is the concrete manifestation of everything that takes place in the instant. Continously. But "free".
@eastwestcoastkid3 жыл бұрын
francoisdeletaille that is an interesting philosophy-but at base Quantum mechanics and Quantum theory hold that physical reality is not deterministic-hence the uncertainty principle.
@francoisdeletaille3 жыл бұрын
@@eastwestcoastkid I think we agree. At some point, reality is determined (observed). But it remains open.
@barryzeeberg3672 Жыл бұрын
just now found this by chance - he is excellent. if they make a movie about him, he would be played by Dustin Hoffman.
@jamshidfaiz67052 ай бұрын
Absolutely brilliant. Thank you for sharing.
@brainstormingsharing13093 жыл бұрын
Absolutely well done and definitely keep it up!!! 👍👍👍👍👍
@victorcortez47911 ай бұрын
Si estuviera traducido al español, seria genial. Excelente Profesor. La UNI siempre destacando.
@luchomarrano11 ай бұрын
Lo cierto que la UNI no hizo nada por él, pudo haber estudiado en cualquier otra universidad e igual hubiera sobresalido, más bien la UNI debería estar agradecido de haber acogido a una mente tan brillante
@s0ulseeker.11 ай бұрын
Aprende inglés en vez de perdir subtitulos, por eso los egresados de la uni muchas veces terminan enseñando de profes en academias 🤣🤣🤣
@AlexanderBlow11 ай бұрын
Ese Barton solo copiaba en la uni yo lo conozco le ponían 20 los profes solo porque su viejita era bien bandida la prra😅
@Diego.Andree11 ай бұрын
@@s0ulseeker.? Por no aprender inglés?, mano como en toda u siempre hay gente que no ejerce su carrera.
@Diego.Andree11 ай бұрын
@@luchomarranoconcuerdo
@italoperezcifuentes606811 ай бұрын
This professor was a former student of one of the best universities in Latin America, the prestigious National University of Engineering (Peru). He was not your average student or teacher. He is a living legend, a GENIUS. Feel privileged to receive their knowledge in your country. Saludos 🇵🇪
@renzosanchez473211 ай бұрын
No me di cuenta de que era barton, such a precious gem of our country. It's a delight hearing his class
@katyvaldez889011 ай бұрын
Si bien la UNI es una de las más díficiles de ingresar en el Perú, no es una de las mejores universidades de Latinoamérica, de hecho, en rankings de universidades, no llega al Top 60 de Latinoamérica. No es por desmerecer nada, pero las cosas como son. Y sí, el profesor es un genio.
@fernandoalejo11 ай бұрын
JJAJAJAJJ prestigiosa por donde wbonazo
@Diego.Andree11 ай бұрын
No exageres man, no es de la mejores de Latinoamérica pero si tiene su prestigio
@mla77292 ай бұрын
Solo no es de las mejor de LATAM porque no sabe investigar seriamente con metodología real. Pero que cubran este hueco y verás como brillará frente al mundo 😎
@tayfun111006 жыл бұрын
Thank you Barton Zwiebach and MIT.
@jeanlacombe36063 ай бұрын
Merveilleux cours de physique ! Merci de partager toutes ces explications si claires 👍
@PauloOliveira-pq3qr3 жыл бұрын
Maravilha de aula! Eu diria um pacote de fótons de aula! Parabéns!!
@JetpackBattle-lc7ob4 ай бұрын
I appreciate the fact he is saying what actually happens with the correct terms, instead of abstracting it all away. I watched a similar MIT lecture but the professor was using terms like "color and hardness" to avoid "confusing us" but for me it made it really hard to picture anything in my head and follow along cause electrons don't have "color" or "hardness" in the classical sense
@lepidoptera93374 ай бұрын
That's an exercise to get students to understand that nature does not consist of phenomena that can be described by commutative algebras alone. It's the big insight of Heisenberg... except that he had to figure it out without help.
@juanjoseph718011 ай бұрын
De los mejores profesores de física.
@sucersdungeon3 жыл бұрын
A great speaker. An inspiring video.
@Carlos_Sernaque10 ай бұрын
La leyenda de la UNI-PERU , Barton Zwiebach👏🏻👏🏻👏🏻
@wulphstein4 жыл бұрын
Glad you figured out that determinism is voluntary.
@BlochSphere3 жыл бұрын
So with respect to Linearity discussed in previous lectures, Beam of photon should be described as Beam |photon_alpha> = a * cos_alpha * |photonX> + a * sin_alpha |photonY> Where a is some constant
@georgestuart8656 Жыл бұрын
What a lovely man. So calm and precise. I remember being introduced to Imaginary numbers at school. POW. Mind blown. Two years later in college, they're vectors. Oh. Why didn't they say that ? On a par with year 2 maths class. Ok. Let's consider n. n is any number ! Pow. n is clearly a letter. Dropped out of the top maths class soon after. Got back in again though. Just the whole year missed and forever holding on by my finger nails since.
@jamesfkeyАй бұрын
Wow, this takes me back to undergrad QM. Sets good foundation for QED. Well done professor!
@suyrai4u3 жыл бұрын
Now I understand What entanglement actually means ! Extraordinary explaination
@user-ul7xl7jq3w3 жыл бұрын
There is a difference in the way of thinking of the inequality sign (or information bra-ket) when we see light as Einstein inertial system and when we see light as quantum entanglement information. Is a very effective inertial vector. In quantum information entanglement, since it is not an inertial system, it is considered as |photon:〈xψy〉:photon|, and it is an information system that should be distinguished from the inertial system, but (photon:ψ>)=(photon: :ψ〉), the optical inertial system and the optical information system are equivalent. This is an important lecture from the perspective of consideration.
@jairofonseca15974 жыл бұрын
This must be the best lecture on loss of determinism on the net, much thanks.
@StarNumbers4 жыл бұрын
You lost determinism when you flip a coin. Write parents to send more money.
@nassimabed4 жыл бұрын
I've seen better
@aravartomian14 жыл бұрын
No
@brivda4 жыл бұрын
@@nassimabed care to share the better video?
@nassimabed4 жыл бұрын
@@brivda I had written that comment a month ago. I have no recollection what this video was about or what other video I was thinking about. Not to mention KZfaq won't allow video comments.
@marktwain6223 жыл бұрын
It's nice to see MIT still using chalk boards, very OG.
@debbiemccoig76722 жыл бұрын
Love this I enjoy it even though I not ready for this
@cesitarc.449011 ай бұрын
Barton Zwiebach the genius from Perú.
@csjfd17646 ай бұрын
excellent explanation ! Congrats, professor !
@worldnewsfoodandbooks82184 жыл бұрын
Looks like Harisson Ford
@stevematson48084 жыл бұрын
After the lecture he's going off to fight Nazis and discover stuff
@stevematson48084 жыл бұрын
Thats Harrison ford doing an accent
@zack_1206 ай бұрын
11:00- Really true, consistent with the wisdom there are more unknown unknowns than known unknowns. 15:25- This statement makes the superposition concept a bit easier to comprehend.
@schmetterling44774 ай бұрын
Nothing he says explains to you where superposition really comes from. If I were to test you orally on that question, I could easily fail you, right now.
@neoaureus4 жыл бұрын
So energising a lecture ! Wow
@sandeepanand3231 Жыл бұрын
Excellent lecture!
@mikefredd33903 жыл бұрын
Now I know what good teaching is. This is a strange world where we know so much but are somehow missing the point completely.
@smcconnell2200 Жыл бұрын
Nicely done.
@smartscience53053 жыл бұрын
Hello Dr. I am 12 years and this video was great , and I wish to be more specification and harder. Thank you
@marcuspradas1037 Жыл бұрын
Brilliant indeed!!
@dariopalomba84203 жыл бұрын
Prof. Zwiebach is actually very good, but for any "not perfect English speakers", it was absolutely necessary the presence of subtitles....in English! Anyway, thank you for the lesson and greetings from Athens, Greece.
@alexandervassilev670211 ай бұрын
Excellent professor
@kskrishnasangeeth4 жыл бұрын
Great explanation
@realsstates11804 жыл бұрын
If all my teachers are this good at explain8ng, I might have turned into a professional student.
@idea2go2 ай бұрын
Great lecturer, thanks for posting this
@SanjayPandit-sc9xx2 ай бұрын
Totally concept clear from this lecture.
@BenTrem42Ай бұрын
_Reminded me of _*_how entertaining physics really is!_*
@kundesumitha2942 Жыл бұрын
great lecture always great onlyyyyy.......hands offf
@yoshirovilchez3392 Жыл бұрын
Grande Zwiebach, recuerdo que nos metiamos unos dotitas en el lab despues de los finales
@josiaszapata698411 ай бұрын
XD
@Diego.Andree11 ай бұрын
XD
@r__9_1____a344 жыл бұрын
He said that hidden variables are not possible, but bells theorem says local hidden variables. Nonlocal ones can exist
@eoinlanier5508Ай бұрын
Nonlocal hidden variables would not be deterministic, though. If information can travel at infinite speed, then events are determined instantaneously, not by past states.
@zhyfn9773 Жыл бұрын
are coefficients cos (\alpha) and sin (\alpha) sort of fitting parameter then? or do they have a theoretical origin given alpha is the state prescribed to this classical state of polarization?
@sarojpandeya78833 жыл бұрын
Amazing!
@carlosalbertocuadros5469Ай бұрын
Good Job Professor
@betanapallisandeepra Жыл бұрын
He is very good teacher…
@ScientificReviewАй бұрын
The funniest lie ever; if they cannot determine it, then the determinism is lost. The amount of grandiosity of the title of this video is ultimate; despite it appears to be super humble.
@eoinlanier5508Ай бұрын
Our ability to determine is irrelevant if there are no local hidden variables. Bell's experiments prove that particles literally do not inherently contain the values needed to predict their behavior.
@lepidoptera9337Ай бұрын
@@eoinlanier5508 There are no particles in nature. There are only quanta of energy. That there can be no local hidden variables follows directly from relativity. We never needed Bell for that. I would advise you to read Bell's paper. He says so himself at the end of it. ;-)
@nathanner28 күн бұрын
great video!!!
@SanjayPandit-sc9xx2 ай бұрын
Thanks sir for this beautiful lecture from India.
@user-zk1dg4tu6l11 ай бұрын
Does anyone know what experiments he is referring to when he mentions people have ruled out the argument "It is the unknown subatomic structure of the polarizer that determines which photos pass vs are absorbed?"
@michaelcheung62903 жыл бұрын
He is brilliant
@surendrakverma5552 жыл бұрын
Very good lecture Sir. Thanks 🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏
@rogermarceloramirezramirez61203 жыл бұрын
Barton
@amj20245 Жыл бұрын
Even Bell himself didn’t think that he proved the impossibility of hidden variables. Travis Norsen: in his book (titled ‘Foundations of Quantum Mechanics’) says: “There is a kind of rich and tragic irony here, in citing Bell as having supposedly refuted hidden variables theories …, Bell’s theorem was actually inspired by Bohm’s 1952 pilot-wave theory papers, and indeed Bell remained far and away the pilot-wave theory’s greatest champion until his death in 1990.”
@ericpham40113 жыл бұрын
quanta was energy unit measurement. if we can program photon in twisted wave guide. is there two type of frequencies minum to have light so should it be Frequency**2 ) * wavelength= speed
@charlesbromberick42473 жыл бұрын
Very nice presentation of a very confusing reality.
@rsalazar97846 ай бұрын
Porfesor Barton, alumno de la UNI - PERU.
@jonathonwoolven2613Ай бұрын
Even Nature herself doesn't know what she's going to do next.
@lepidoptera9337Ай бұрын
That's exactly right. Good intuition!
@js-fx6vm Жыл бұрын
The figure in this explanation would be better if shown in three dimensions. The professor’s explanation describes a plane wave oscillating in a plane parallel to the z-axis at an angle alpha to x--z plane. Then the closer the plane of the wave gets to the x-z plane, the greater the transmission of the wave through the polarizer.
@tomnoyb83013 жыл бұрын
Polarizers are not filters, they are re-radiators. Imagine two antennas connected by a coaxial cable. The interfaces between glass and air are the antennas and the glass is the coax. Light impinges the front face, just as an antenna. If the antenna's polarization matches, the light enters the glass, propagates and exits according to the polarization of the back face (antenna) of the glass. Using this correct model of a polarizer explains polarization completely and without mystery. Bell's Theorem is not required, only Maxwell's equations.
@williamnelson4968Ай бұрын
Can you give me any reference (book or article) that supports your re-radiator model of polarization. Many thanks for your insight.
@IanHarrison-xo5kf Жыл бұрын
Great lecturer
@CarlosLeon-ii2fs Жыл бұрын
Increíble un ilustre Peruano haciendo patria en el extranjero.
@jnananinja74363 жыл бұрын
Just listening to this thinking... Damn!.. Borat knows his QM!
@dougr.23984 жыл бұрын
Bell’s Theorem and experiments with photons were the subject of my oral exam for admission to Doctoral candidacy in 1977.
@dougr.23984 жыл бұрын
The most interesting thing I found out about Bell’s theorem was that it was based on an error that J.S.Bell found in VonNeumann’s “Mathematical Foundations of QuantumMechanics”
@eastwestcoastkid4 жыл бұрын
Doug R. What was the error, and did you do your Doctorate in Quantum theory?
@dougr.23984 жыл бұрын
eastwestcoastkid I’d have to review Bell’s collected published works (papers in scientific journals) as I believe it may have been referenced in at least one of his papers, and no.... I decided that an experiment was not necessary at the time, some years before Alain Aspect was funded for his own research, which found the expected result (in support of Quantum Theory). I eventually left Physics research, after switching to the low temperature physics group, and some five years after leaving that, left teaching for another career path.
@volcano868Ай бұрын
the clue is in the title guys - Open Course. For anyone who wants to watch. And you've got to be pretty good at your subject to explain quantum physics so that anyone can even approach understanding that!