Photons and the loss of determinism
Vložit
- čas přidán 4. 07. 2017
- 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
Que nivel de clase de este profesor . Orgullo peruano .
No es peruano es Judío Ultramar. Judío ...
@@elitedelobos Puede ser de origen judío, pero nació en Lima, creció y estudió en Lima, graduándose de la Universidad Nacional de Ingeniería. Es recontraperuano
@@juanrodrigovalencia No. El siempre la tuvo clara. Es un judío y tiene nacionalidad judía.
@@elitedelobos En serio? Y tiene pasaporte "judío"? Por favor JAJAJAJJAJA
@@elitedelobosmira mongol si Vienes a opinar sin info mejor ni opines lapiz😅
This is brilliant. This professor explains things extremely clearly.
Agreed totally. His pacing also is fantastic
Lol.
He is a pseudo scientist!
I'm 12 and I got it too
Does he tho ?
Barton, el único estudiante en la historia de la UNI que se graduó antes de terminar su carrera.
El mejor alumno de la historia de la UNI.
Es de mi facultad
@@ARCP-mj1mrq nunca lo ejerció
@@paultarazona7989XD
@@paultarazona7989😂😂
Buena la profesión le sirvió para hacer investigación, dónde invierten otros países extranjeros.
"That's what polarizers do for a living" :)
lol
.... what percentage of polarizers are unemployed .. that's what I wanna' know ... it seems the good professor overlooked this dilemma during the lecture ..... hmmm .....
The polarizer proves that light is a wave and not a particle.
@Phoenix do you think Trump is a real president?
@Phoenix when the Suits come for you, don't answer the door.
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!
Besides the wonderful clarity in his lecture, I am amazed at his very clear, beautiful, and organized writing on the board.
Such amazing job Mr. Zwiebach! Thank you...
"It's a debacle! A total disaster!"
Great Teacher. Takes time and explains well. Defined indeterminism very clearly.
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.
Brilliant lecture given by Barton Zweibach Sir .....
This exposition is as clear as can be
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.
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.
there's something about writing on a chalkboard that just makes it much better than presentation slides as a teaching medium for showing equations
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.
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.
Well spoken with excellent handwriting. A rarity among physics professors
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.
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.
peruvian's proud!
@@andressuarez6153 así es.
Thank you MIT and sir. Wish him long life and happiness.
I really like his handwriting
This looks so passionate
In that case I advise you to check out Nima Arkani-Hamed.
What a wonderful teacher you are, if I may say so. Thank you for sharing this lecture with the public. 🤓
A shill can only repeat the obvious -- it's in the public.
🙂
Bertrand de Born really?
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 😃😉
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.
Well spoken with excellent handwriting. A rarity among physics professors. Maravilha de aula! Eu diria um pacote de fótons de aula! Parabéns!!.
thank you MIT, thank you sir, and thanks to whole staff there.
Si estuviera traducido al español, seria genial. Excelente Profesor. La UNI siempre destacando.
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
Aprende inglés en vez de perdir subtitulos, por eso los egresados de la uni muchas veces terminan enseñando de profes en academias 🤣🤣🤣
Ese Barton solo copiaba en la uni yo lo conozco le ponían 20 los profes solo porque su viejita era bien bandida la prra😅
@@s0ulseeker.? Por no aprender inglés?, mano como en toda u siempre hay gente que no ejerce su carrera.
@@luchomarranoconcuerdo
Good and clear teacher. Good tempo and very to the point.. Absolutely well done and definitely keep it up!!! .
Wow, clearly explained and at a pace I can work with. Gonna be watching more of these.
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
Yeah pretty good argument 🤷♂️
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.
just now found this by chance - he is excellent. if they make a movie about him, he would be played by Dustin Hoffman.
Man, I just enjoy listening to his voice....
Me tooo I swear to God 😄😄😄😄
Good and clear teacher. Good tempo and very to the point.
Maravilha de aula! Eu diria um pacote de fótons de aula! Parabéns!!
Merveilleux cours de physique ! Merci de partager toutes ces explications si claires 👍
This professor is one of the best
Wow, this takes me back to undergrad QM. Sets good foundation for QED. Well done professor!
Thanks for the lectures!
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
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.
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 🇵🇪
No me di cuenta de que era barton, such a precious gem of our country. It's a delight hearing his class
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.
JJAJAJAJJ prestigiosa por donde wbonazo
No exageres man, no es de la mejores de Latinoamérica pero si tiene su prestigio
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 😎
La leyenda de la UNI-PERU , Barton Zwiebach👏🏻👏🏻👏🏻
Wow !...A professor who writes cursively ! 🎊🎉🎊
De los mejores profesores de física.
It depends what you mean by determinism. Everything is still determined by the laws of physics - even if these laws contain uncertainty
116 dislikes show jealousy of not having best teachers like him
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.
These lectures are awesome!
Absolutely well done and definitely keep it up!!! 👍👍👍👍👍
A great speaker. An inspiring video.
Absolutely brilliant. Thank you for sharing.
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
Grande Zwiebach, recuerdo que nos metiamos unos dotitas en el lab despues de los finales
XD
XD
Barton Zwiebach the genius from Perú.
Wow. The universe it truly random. Thank you.
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.
Now I understand
What entanglement actually means !
Extraordinary explaination
excellent explanation ! Congrats, professor !
Thank you Barton Zwiebach and MIT.
This must be the best lecture on loss of determinism on the net, much thanks.
You lost determinism when you flip a coin. Write parents to send more money.
I've seen better
No
@@nassimabed care to share the better video?
@@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 CZcams won't allow video comments.
Glad you figured out that determinism is voluntary.
Looks like Harisson Ford
After the lecture he's going off to fight Nazis and discover stuff
Thats Harrison ford doing an accent
Good Job Professor
It's nice to see MIT still using chalk boards, very OG.
Now I know what good teaching is.
This is a strange world where we know so much but are somehow missing the point completely.
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.
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.
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!
I'm searching for memories of a long finished trig class.
Great lecturer, thanks for posting this
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.
_Reminded me of _*_how entertaining physics really is!_*
Hello Dr. I am 12 years and this video was great , and I wish to be more specification and harder. Thank you
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.
Increíble un ilustre Peruano haciendo patria en el extranjero.
Totally concept clear from this lecture.
He said that hidden variables are not possible, but bells theorem says local hidden variables. Nonlocal ones can exist
Nonlocal hidden variables would not be deterministic, though. If information can travel at infinite speed, then events are determined instantaneously, not by past states.
Thanks sir for this beautiful lecture from India.
Excellent professor
Excellent lecture!
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.
"If one gets through then all should get through" - No, and that does not imply there is loss of determinism. Just because we don't know (or understand something) does not imply it must be random!!!! They are identical, yes but the background is always in flux!!!!
Great explanation
So energising a lecture ! Wow
Porfesor Barton, alumno de la UNI - PERU.
Nicely done.
Doesn't Bell's inequality say that no LOCAL hidden variables can satisfy quantum physics meaning that NON-LOCAL hidden variables could satisfy it?
Bell’s Theorem and experiments with photons were the subject of my oral exam for admission to Doctoral candidacy in 1977.
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”
Doug R. What was the error, and did you do your Doctorate in Quantum theory?
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.
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.”
Love this I enjoy it even though I not ready for this
He is very good teacher…
Very nice presentation of a very confusing reality.
Very good lecture Sir. Thanks 🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏🙏
great lecture always great onlyyyyy.......hands offf
I was about to sleep, but here I am taking notes..
Algorithm.
Bell just showed that a HVT is non local and, if the formalism of spin is correct, that it is also contextual. Look at the interpretation of spin in the works of David Hestenes and other physicists, and contextuality desappares
you're assuming that waves only move forward, in time, in space. But waves do not behave as we would like them to.
Surely - when we observe light as a wave, it behaves as a wave (Polarization, diffraction, superposition), and when we observe as a particle, it behaves as such. (Photoelectric effect).
I get the feeling that you are asking the light to behave like (Commit to being) a wave and then questioning what happened to its particles...
As far as photon/polarizer debacle: could it be that the photons are entangled in opposite spins and the spin is the deciding factor as to whether the photons goes through.
If all my teachers are this good at explain8ng, I might have turned into a professional student.
I took some acid and I’m watching this feels like I can make a photon accelerator after watching this, shout out to g for dropping this lecture
Brilliant indeed!!
He is brilliant
Great lecturer