Surprised you didn't mention the part of that experiment where they took out the center of the mirror where it's supposed to reflect the most and then it still made it to the detector

Considering Feynman replaced Schrödinger and Dirac in one fell swoop, his insights are incredible!

Honestly your explanation and visuals really helped me follow the whole way through, and I’m dumb af so great work!

That was absolutely superb. QED is a mind-blowing book, Feynman is second only to Boltzmann in my humble estimation (maybe the 2nd LoTD could be a future vid?) I know diffraction gratings are the more common method for practical reasons, but I would have shown the diffraction lines with a single frequency light that Feynman used to explain it. With lines drawn in just the right places you can make a mirror that reflects at any angle you choose. So you can fire light at a mirror at 45 degrees and have it bounce straight back. It's used in scope lenses to correct for chromatic aberration if I'm not mistaken. Great animation btw, the displacement/bump texture on the brick was nice. I was particularly impressed that you locked the rotation of the arrows to the X axis position of the two other objects. Doing it with one is one thing, making it a function of both would have been hard, I'm guessing you coded some python into the driver if you used blender, unless of course you used an animation node set up. Actually, now I'm thinking it's maybe Unity or Unreal. Regardless, very impressive work.

I was watching this, thinking it had millions of views... Only 4k??? Hopefully your content gets boosted by the algorithm. Absurdly good quality for the credit you're getting in viewership. You deserve far more.

My god these visual representation are sooo amazing, this was so well explained i love knowledge so much

This is such an excellent presentation of Feynman's QED ideas! And the animations are beautiful. If they were done with Blender, they would take weeks, possibly months to do. I found two possible errors in the presentation. The first is a statement that we cannot make predictions, only state probabilities, especially in the very tiny regime. This is not true of QM, but is an axiom of the standard (Copenhagen) interpretation, forced on physics by Neils Bohr. I won't waste space here explaining why the better interpretation, Bohmian mechanics, is not better known, but in that interpretation it is possible to observe the trajectories of individual fundamental particles and verify that they are deterministic, not governed by probability. Where they land on the screen of the double-slit experiment =is= probabilistic, but individual photons remain particles, never acting as waves in the experiment. I will say more if there are questions, but this is what Bohm stated in 1952 and it has been confirmed by experiments. The second possible error is the statement that Heisenberg uncertainty is the reason we can't explain double slit behavior. This is wrong: measurement of complementary uncertainty only explains why position and speed cannot both be measured simultaneously. The real reason for strange QM behavior is nonlocality. In the double-slit experiment, we see two different patterns on the screen depending whether one slit is occluded or not. Even measuring the particles at one slit produces the same change in pattern. This is the only mystery in QM, and it is fully predicted by the Schrödinger equation, which depends only on the geometry or arrangement of the experiment. It is as if one could capture the effect of bombarding or illuminating the experiment by waves of various frequencies in one equation. By itself, the Schrödinger equation cannot make specific predictions about measurements, the important basis of physics. This is why the standard interpretation always focuses on probability distributions. But simply add the initial positions of all the particles, and the Schrödinger equation becomes the basis for predicting particle paths with precision and determinism. This was the achievement of David Bohm, which has yet to be discovered by most physicists for purely historic reasons.

dude your videos are amazing! the editing is phenomenal and the explanation is even better. The algo really did well recommending you to us.

I have seen this concept explained several times before but this was probably the best and clearest explanation of this concept, great video

I love it! I love your videos. You explain Quantum mechanics so well.

I absolutely love your channel. You’re so fricking underrated. I am so happy i found this hidden gem!

I could understand this more intuitively if what you were saying is that a torch spewing photons in a wide area creates probabilities that add up/cancel out etc and that's what causes these reflective and refractive phenomena, but from what I can glean, you are saying that even just one photon has all these different probabilities about where it will reflect? This seems very odd to me. I thought a photon would travel in a straight line and reflect/refract in a predictable manner. I suppose this is what you mean by it being unintuitive.

Your visualizations are amazing. Keep up good job man! 👍

This is a TERRIFIC video!!! Thankyou so much for explaining in terms that most people can understand. I usually have a difficult time comprehending wave/particle duality (particle-wave?) but this video explains it probably the best I have seeen so far, like EVER. 👍 Great visuals too- they help A LOT!!! And also, much thanks 🙏 for mentioning the revered Richard Feynman. What an awesomely creative person. Keep up good work and I def understand this concept a lot better!

I love these animated explanations. Really helps to visualize everything. Thank you

Great stuff. But can I ask what reflection is? Does the photon interact with the electrons on the reflective surface in any way? If so, does that not constitute an 'observation' and collapse the waveform?

My new fave channel. Keep going!

Incredible explanation.. How come you channel doesn't have millions of subs.. Awesome animations man.. How much time did it take you to be able to be good enough in Blender to make these animations..?

Superb ! I bet Feynman would really appreciate such wonderful animations vs. his old chalkboards(with a few colors when lucky). 😂

Thanks for clearing up thin film interference for me almost unintentionally

Wow!! Another level of teaching...

Excellent summary of Feynman's description in QED.

You nailled it! Thank you. ✊🏾

My favorite Feynman quote... There is a big difference between knowing and understanding. So true. Many people can parrot what is said in this video, and do the equations, but understanding it is a different story. ( I can do neither, so... )

Mind blowing and beautifully explained.

thanks for this really nice video, and props on the intro.. it was a smart move :)

🏅Great visual explanation🎯. Thanks for sharing that vast knowledge! ♥️

The best video I've seen on the subject.

Subscribed. Great work buddy

With regard to the quote from Feynman at 1:20 about prediction, Niels Bohr said "Prediction is very difficult, especially if it's about the future." Hard to argue with that.

This final explains the whole wave thing I was hearing about quantum stuff. Now I get it

best explanation that I have heard yet

This video was awesome!

I keep thinking I've seen all of your videos and then KZfaq treats me with new ones 🙏

You will give strong competition to Science Asylum. I Love Both of You 👌🏻👌🏻

wow. great way to explain if you ask me, thumbs up !

This was way more complicated than I imagined. But great animations.

This is full of unvaluable insight

This is a pretty good explanation, though I take some issue with the last sentence that implies a better physical theory might fix quantum weirdness. There are a ton of quantum information results and experiments that suggest this quantum weirdness will not go away. For reference, see the CHSH game and the bell inequality.

LOL at the blue man dancing in the beginning

Diffraction is amazing! Geologists can identify minerals in thin sections thanks to diffraction

I love this video !

But why? can you tell me what song is the one you have used in this video? thank you.

Would love to see your take on Rayleigh dispersion

This video is great! But it left me with a possible stupid question though: if light travels at the speed of causality and therefore doesn't experience the flow of time, how does it cycle through phases while it moves?

Facinating video :thumbsup:

which software you use for these animations ? it's awesome

can you make a video about solar panels, LED, semi-conductors? I am intrested about your explanation...I saw you put a little more details in comparison with other creators

I've learnt a lot from this channel, and if I'm understanding things right regarding probability in our universe. At a quantum level it's much less predictable because of probability, and at a macro level it's more predictable, also because of probability. So all the little unpredictable quantum level events are almost 100% predictable when all combined on a macro level. If i have that right, would that mean there's an almost infinitesimally small chance something catastrophic could happen on our macro level? Based on probability?

Thank you for sharing helpful and informative videos! Just as Time and Fortune are higher orders of existence, perhaps there are deeper orders of nature. How could this be relevant to all Life?

so this is what Bartosz Milewski was talking about as a global perspective on light travel as a category theory for programming

Light 'avoid' 'suffering' / 'cost' / 'corruption'. Shortest path. Its behaviour.

Hello. Your visuals and some parts of the video are good but I would like to point out that the quantum description of the reflection of light and related phenomena that you have provided here, involving the principles of quantum electrodynamics (which I assume have been inspired by the book on QED by Feynman) are inaccurate. The book and the theory alike do not say that the emitted photon travels all the possible paths simultaneously and that each “reflection” some how interacts with the other possible ones to yield the final most probable and classically intuitive central path where the angle of incidence equals the angle of reflection. This is a false inference. The theory and the book state that, for an ungrated mirror, nothing can be said about the path that the emitted photon will take to reach the detector and this goes against the principles of determinism on which classical physics is based. Intact, it cannot even be said with certainty if this concerned photon will reach the detector at all in spite of the fact that the detector reads the incident light. Only the chance of this occurrence can be calculated and in order to be able to calculate this chance, the classical notion that light travels in straight lines will have to be abandoned and each possible path must be considered No matter how curved. Once done with the calculations , the final probability of the occurrence of this event will be attained. Then it is seen which paths contribute the most to this chance so calculated. It turns out that due to the vector addition of the phases associated with each path, only a few paths contribute the most to this probability and these happen to be the central path (where the angle of incidence is equal to the angle of reflection) and a few lying close to it. That’s it! Weather the photon traverses all the paths simultaneously or chooses any of these paths is not discussed by the theory and no mystical final interaction of all the reflections making them collapse into the central path has been proposed. The theory is strange not because the photon reflects off the surface of the entire mirror all at once but because nothing can be determined about the path it takes or why it takes it and it is not even considered relevant. Everything is reduced to chances

Yup totally understood everything. Definitely did not fail physics

I would love to hear explanation of reflection physics, my understanding is that photon-wave is not reflected, it is absorbed and re-emitted with gradient of probability in which the angle is preserved for same reason we see light taking shortest straight path..

Aight subbed

It breaksdown White light into colours Purple Blue Green Yellow Orange Red energies which tells us the effects on each person. Green energies are very powerful as they give us our Souls and Holy Spirit's Gods way of confirming our Eternal life! Give praise . MBraithwaite zYorkshire Viking

Brilliant. Don't we also square the final arrow to get the probability value?

Hmm, not liking a theory is a good motivator to find alternative theories that have the same or better predictions. On an unrelated note, I wonder what pilot wave says about QED. I'm not well versed in it, do the pilot waves guide the photons as well? Are they moving at light speed?

Nice

What was the music at the end?

8:10 Was this experiment actually done where there's so many sloped mirrors? I Want to see it

If a photon moves through space constantly oscillating (3:05) then how fast is it moving? It seems like the answer should be at the speed of light but that can't be it because of time dilation objects moving at the speed light experience no time and without time oscillating is nothing. The equations of QM are very useful for predicting what will happen but that doesn't mean every or any interpretation of the equations should be taken as truth. In the animation each arrows represent a probability amplitude but how does a probability amplitude get reflected off a mirror? Are probability amplitudes physical things? Or are they mathematical constructs that map on to reality but shouldn't be mistaken for reality just as any map shouldn't be mistaken for the territory it represents.

That's cool

for anyone that doesnt know, the length of this video (11:37) is an easter egg.

I like your funny words, Magic man

Is *_Wave Phase_* different to *_Polarisation_* ???

Why is there a flash of light when showing the oil reflection?

Song?

You had me up to the point you reinforced the mistaken notion that QED is "bizarre". Nature isn't bizarre, it just is the way that it is, and whatever strangeness is assigned to it is all in our mind. At this point we understand enough that it is only this constant reinforcement that sets an expectation ahead of time that prevents students from forming natural intuitions about how QED works.

one problem: if you have an asymetric mirror, so only one curly bit of your probability arrows, there is no increase in brightness. so this superfluous model is wrong

I kind of get some of this but I don't yet.

Why this Video has only 4k views?

" An intelligent fool can make things bigger and more complex... It takes a touch of a genius and a lot of efforts to move in the opposite direction "... This channel is the later part in this above statement

0:49 "there is this possibility. After I tell you something, you just can't accept it. You don't like it. A little screen comes down and you don't listen anymore" This hit so close and I could feel the weight of far too many interactions with far too many people rushing into my memory as I read this. I cannot put into words the feelings of exhaustion and hopelessness that come over me when someone shuts down because they simply don't like the science. I'm basically middle aged now and I still struggle to understand why so many people do this.

Maybe some podcasts? 😏

🖖⚡️

Damn, after the last part of the video it made me realise how primitive humanity as a whole is

But aren’t the colours in the oil caused by interference?

Who does he mention at the end: "Feynman couldn't, Hawkins couldn't.." ?

Why the obsession with light though? Light (visible light) is only a small fraction of the full spectrum of RF. If you ignore light, and use lower frequencies of RF, and larger scale models, is the universe really all that mysterious? It seems constructive/destructive interference, happens at all scales, but because light waves are so small, and visible to the naked eye, some otherworldly woo woo is cast upon them. What gives?

But...but...couldn't the same phenomenon be explained by a photon or electron being a teeny energy particle defracted by microscopic inconsistencies of glass texture,or air itself in the slit experiment? -curious noob

feynman is the goat

YES BUT WHYYYY

quantum electrodynamics? science starting to sound like geometry dash levels smh

Yeah no yeah I understand this for sure haha uhhhh

Why does he sounds like bill gates

Are you a physicist ?

This is a test comment

what the fuck.

0:45 Consciousness is virtualized reality. Look into synesthesia and phantom limb syndrome. Light ceases to exist at the retina and becomes a cascade of electrochemical signals until it is perceived as “color” at the prefrontal cortex. Light exists. Colors do not. 3:00 Your representation is incorrect. The “photon” is a is a spherical wave front that induces an oscillation on every electron in the conduction band of the mirrored surface, which is usually silver. The electrons in the conduction band of a metal are loosely bound to their respective atoms which creates a “sea” of loosely bound electrons. These electrons have a greater freedom of movement parallel to the surface of the metal. This is why “reflected” light is polarized parallel to the surface of “reflection.” I put “reflection” in quotes to highlight the fact that the photon from the light source is actually absorbed by the electrons in the reflective surface. As the electrons oscillate, they induce new wavefronts. The incident wave front does not “bounce” off the material. It is absorbed. The same happens with the Moon. Light from the Sun is absorbed by the material on the Moon’s surface. Most likely valence electrons or smaller atoms are caused to oscillate in some way or molecular bonds being forced to shorten and lengthen in molecules. These induced motions then create new electromagnetic oscillations. So, technically, the Moon does generate its own light. Everything does. This is, by the way, how Rayleigh scattering leads to “blue” skies during the day. I believe it is the N2 molecules absorbing that frequency of light then radiating new light as its induced oscillation dissipates. 3:30 Not only is the phase different, but the amplitude is directly proportional to the inverse square of the distance. The wave front is a two dimensional spherical surface which increases in area directly proportional to the square of the radius. 4:00 There is no probability of path taken. The probability is the sphere interacting with a conduction band electron. Remember, the light REFRACTS through the glass surface BEFORE it REFLECTS off the metallic surface. Technically, a small portion of the light energy is reflected off of the glass as well. 8:00 This phenomenon is called “iridescence.” You also see it occurring in insect wings and various feathers like on peacocks. Microscopic structures are built up in steplike patterns that reflect light of different wavelengths at slightly different times creating the same effect. 10:00 These diagrams SUMMARIZE what is happening. They do not DESCRIBE what is happening. The probability wave merely predicts the final outcome of the sum of all the resultant waves from every electron that has been induced to oscillate. It’s like the wave front pattern produced when a pebble is dropped in still waters. The diagram SUMMARIZES where all the constructive interactions between all reflected waves occur, but it does not DESCRIBE the motion of every wave in the system. 10:30 A spherical wave front radiates outwards. It doesn’t “take the shortest possible path.” What you are seeing is the resultant interaction of innumerable wave fronts interfering with each other. 11:00 Because a “photon” is a spherical wave front, not a packet of energy.

I'm Mr meseeks look at me

Hawking... not Hawkings... you have at least get his name right lol, you need to talk about magnetic resonance

1:20 the arrogance of a physicist to say such a thing given the absolutely pitful state of the modern discipline. We barely know anything at all about our universe, but he has the balls to state this about often irreplicable and even bias experimentation? Physics is full of one-off flukes that get branded as groundbreaking, yet can't be followed up. Even just looking up "Replication Crisis" will render dozens of articles relating to the subject, so I don't need to bs you here in chat. We just need to keep in mind that everything we know could be totally wrong.

half the video so far, and I haven't heard one word of diffraction, or maybe I'm just too confused in your wasted time. get to the point. I haven't even heard you mention colors

Great content, unnecessary terrible background music. Thank you.