Are you a particle or a wave? Photon: *yes*

@UjjwalKumar-wg4wu

3 жыл бұрын

I am a particle and travel in wavy direction

@nguyenhoanglong420

3 жыл бұрын

Photon is a wave !! But it has so much waves that can create a shape like particle but photon is actually a Waves !!! Photon is a set of Waves combine to become Particles

@nguyenhoanglong420

3 жыл бұрын

@@UjjwalKumar-wg4wu Photon has a shape like Particle but it's actually a wave!!! I mean Photon have a lot of WAVES

@PasajeroDelToro

3 жыл бұрын

It's a candlestick, like in the stockmarket. Lookup Leonard Troland. imgur.com/a/xQbuukM archive.is/0I6Rp

@nazarissa9494

3 жыл бұрын

Same for human😁

This was the moment when Walter White truly became a photon.

@vinayakzzz5934

Жыл бұрын

waltuh waltuh

@Joshua-dl3ns

Жыл бұрын

Bravo Vince, he did it again

@UnkownUnkown01

Жыл бұрын

Photonberg

@nomanaziz804

3 ай бұрын

Done and dusted

I want you to know how timeless your videos are! This randomly came up in my feed since I have seen some of your videos before, and I was just as entertained and intrigued as any newer videos you’ve made!! Truly amazing thing not many can accomplish. GREAT work, and thank you for all you do!!!!!!!

The background music, the passionate energy of this guy and the instrumentation are what I believe the keys that the video is awarded with so much views. Keep the good vibes going Veritasium!

@mrlawilliamsukwarmachine4904

5 ай бұрын

It’s because of Breaking Bad!

I tried defying Heisenberg's principles once. ...I ended up in a barrel buried in a New Mexican desert.

@mickelodiansurname9578

7 жыл бұрын

Zach Gilbert well lucky that was in the past.. if it were a few years from now you'd need to also climb a wall to get back into the US.

@oreole9608

6 жыл бұрын

You are really lucky you didn't end up on the Moon or something.

@fandomguy8025

5 жыл бұрын

@Mickelodian Surname, He said *new mexican* as in the state "new mexico".

@badhombre4942

4 жыл бұрын

Ha, rookie mistake. You have only yourself to blame for your position and lack of momentum.

@namanpal123

4 жыл бұрын

For any one of you who didn't understand what the op meant : It was a reference to breaking bad show .

On this day in 1927, Werner Heisenberg first proposed his famous uncertainty principle. Though the date of this discovery is known with precision, Heisenberg's whereabouts at the time remain a matter of speculation. ;) Check out my video on a counter-intuitive demonstration of the uncertainty principle. Heisenberg's Uncertainty Principle Explained

@hxhxhgfd

9 жыл бұрын

***** The short answer is that physicists don't currently know why they follow these rules. They just know that that's how the world operates.

@daviddennetiere9217

9 жыл бұрын

Veritasium Seems like a nice demonstration, but by looking at the equations, i got a 4pi factor hanging around suggestion Heisenberg is only responsible for less than 10% of the broadening... In deed, diffraction says the first zero happens for d*pi/lambda*sin(theta_z) = pi => theta_z = arcsin(lambda/d) But Heisenberg only suggest that d*h*sin(theta_z)>= h/(4*pi) => theta_z = arcsin(lambda/(d*4*pi)) (at the limit) given, the micronic width of the slit, we could linearize the arcsin which leaves Heisenberg width twelve times smaller than the width of the spot as predicted by diffraction... Don't mistake me though, I like your work ^^

@rich1051414

9 жыл бұрын

***** It's an intrinsic attribute, not a flaw in our ability to measure. Look into quantum mechanics.

@MrProgrampro

8 жыл бұрын

***** With regards to knowing precise position at the same time as velocity and vice versa: It's not "unknowable" in the sense that we think we can't know it, it's "unknowable" in the sense that there's nothing to know: a precisely-bound-in-position particle has a 'blurry', ill-defined momentum (ie. wide probability distribution function in v) and a precise-momentum particle has a blurry position. I'm not a physicist, but I have heard it has to do with the fact that each of these quantities is the fourier transform of the other. Tall, precise peaks get fourier transformed into wide, imprecise hills, and vice versa.

@MrProgrampro

8 жыл бұрын

Well that's a great question :) After all, empirical observation is the most important thing when it comes to understanding our universe. Frankly, I don't know much about this, but I'd suspect based on things like the phenomenon shown in the above video that when scientists try to restrict a particle's position, its momentum goes all over the place in a probability distribution, and similarly for restricting its momentum.

imagine being a renound scientist, dedicating a huge amount of time to researching and developing a breakthrough principle, only to have a guy who cooks meth in an AMC tv series named after you who like ten years later gets memed on by the internet

@MK-rn1mg

2 жыл бұрын

Imagine a man watching that TV series and laughing at memes, then looking up who Heisenberg is, who Gödel is, getting hooked on physics, discussing physics and science with son at young age and that son now pursuing scientist career. Imagine - what if the character had a different name in the TV series…

I really have the most appreciation of this channel now than ever before. Showing these experiment and clearly explaining the principles behind the physical laws is awesome!

jesse we have to cook

@medhawinikapoor4735

7 жыл бұрын

ok

@lightnox8388

3 жыл бұрын

@Dinesh Pandey valar morghulis

@justsomeguy892

3 жыл бұрын

jesse were is the cocainer

@abhikchakraborty5616

3 жыл бұрын

OP... . Only breaking bad fans can get this....!! 🤣🤣🤣🤣🔥🔥🔥🔥

@malavpatel1135

2 жыл бұрын

Methamphetamine

I am a PhD Student working on Molecular Dynamics and I deal with Quantum mechanics on a day to day basis, I have attended so many lectures on Quantum physics, quantum mechanics, statistical dynamics etc. But I have to tell you this mate , you explained Heisenberg's uncertainty principle better than anyone else I have heard it from. And believe me when i say this, I have heard explanation for it from at least 20 different professors, lol. Veritasium Good job mate, Keep it up

@SteveLPDNB

3 жыл бұрын

How did your PhD go? Also what UK uni were you at?

@tanmaykarde

2 жыл бұрын

@@SteveLPDNB It's been 7 years

@harishthethird

2 жыл бұрын

@@tanmaykarde oooof

@roshanthapamagar1318

2 жыл бұрын

You doc yet? ;/

@parvashah2671

2 жыл бұрын

I beg to differ. Slit experiments were supposed to show that the light has a wave nature. Here he is showing that light has a particle nature. Wth is going on?

Great stuff! I spent all evening looking for some good resources to show students on this, and this is by far and away the best thing I have found.

Awesome!! You made this so easy to understand. I've always hated working with formulas. You've ignited my interest again!

A physicist went for a drive and got stopped by a traffic cop. - "Do you know how fast you were going?" - "No, but I know where I am." xD

@EnellGmz

10 жыл бұрын

***** Watch the video again.

@elmohead

10 жыл бұрын

***** You can either determine the speed of an electron or its position, but not both.

@TosiakiS

7 жыл бұрын

Though you still need to have a bit of uncertainty in one of them, otherwise the product of the uncertainty of position and uncertainty of velocity would be 0 since anything multiplied with 0 would be 0.

@kevkasim

7 жыл бұрын

+elmohead It's not speed its momentum. The symbol for speed is v but the equation uses p wich stands for momentum.

@rubiks6

7 жыл бұрын

it's a joke that you didn't get, kevka.

this explains why people who wear tighter and tighter pants tend to look fatter

@cyberschn1tzel997

8 жыл бұрын

Verirektium

@f00zh

8 жыл бұрын

+Hugh Jass good answer , hugh jASS

@faxrialiyev3711

8 жыл бұрын

+Hugh Jass genius!

@jas672

8 жыл бұрын

Brilliant! 😂

@emp3202

7 жыл бұрын

hahahaa

Thank you so much for making an accurate description of the effect, i hate it when well known channels confuse it with the observer effect

MAN i really can't stop thinking about how great you're being to the people on earth!! congratulations you are making an amazing job! you are making us THINK, something very needed these days! A huge thank you from all of us at Brazil.

The problem I have with this video is that it does not explain Heisenberg's uncertainty principle; it merely demenstrates it. I want a video showing WHY Heisenberg's observation is correct; what is it about the universe that makes these subatomic particles disinclined to be observed precisely in regards to position and momentum?

@jpheitman

10 жыл бұрын

God dammit, *demonstrate.

@REDSHIFTEDuk

10 жыл бұрын

Very late reply but if your still curious Brian Cox explains it very well in his book. He also proves using a few equations. The book is "our quantum universe-everything that can happen does happen"

@ivorclark2523

10 жыл бұрын

My understanding is that it is an instrumentation problem. If we use photons to observe photons they will interact with each other, changing the properties of the target photon. So use lower energy photons, but then the target becomes dimmer to observe. So use something smaller like electrons, which are even harder to see, but they still interact with photons and change their properties. Basically you cannot " observe" a target photon or electron with other photons or electrons without changing its very nature, defined in terms of where it is and how it is moving. To me this experiment illustrates simple diffraction, not the difficulty in determining a quantum particles position or momentum....

@fandomguy8025

5 жыл бұрын

@jpheitman Very very late but here you go: kzread.info/dash/bejne/f3ai0Lqbf7Cbg5c.html&vl=en

@fandomguy8025

5 жыл бұрын

@Ivor Clark, hope you know better in the 4 years that have passed but if you do not. No, it's not. It's due to the wave nature of matter. kzread.info/dash/bejne/f3ai0Lqbf7Cbg5c.html&vl=en

It's a shame the video isn't translated to more languages. I made a translation into Russian to spread your word wider =) Thanks for your work!

@jpmorgan187

4 жыл бұрын

Everyone should learn English

@erezsolomon3838

2 жыл бұрын

@@jpmorgan187 but don't count on it

@shannonmoraes6282

2 жыл бұрын

@@jpmorgan187 nope

@COVID--kf3tx

2 жыл бұрын

@@jpmorgan187 They really shouldn't. Science has no language

@nostalji75

2 жыл бұрын

@@COVID--kf3tx id argue it does. Actually all languages "serve" science, since they are tools to express our thinking. We are limited by their limitations. The most useful language for science would be math. I consider math a language wich is designed for science.

Thank you for this video, it is really pedagogical and illustrative. This uncertainty principle is hard to explain but you did well. Thank you once more.

Excellent way of explanation! Keep making such videos, I really enjoy!

02:30 - "now photons must veer of to the left or right to ensure we don't break Heisenberg's relation" well, this is not the line of thought I like. The laws of physics are not like laws of men. The particles do not behave the way they do in order not to break some law. They do behave the way they do because and the laws and equations just describe that. Derek, kindly tell us why exactly do the particles change their momentum when going through the narrow hole.

@mohammadtausifrafi8277

8 жыл бұрын

+panda4247 The photons do not do so consciously, of course, it happens as the uncertainty cannot decrease too much due to the laws of physics in our universe.

@esp1344

8 жыл бұрын

+panda4247 well that's the issue aint it. you do all these fancy experiments to answer the question why and you get this fascinating law that says that the certainty to which one can measure both the position and momentum of something cannot exceed this limit. why? well who the hell knows >.

@liamvance966

8 жыл бұрын

EXACTLY I really missed that in this video

@Plumjelly

8 жыл бұрын

+panda4247 Photons are fined very large amounts of money, and are given community service if they don't follow physical laws properly. If we want them to behave differently we just need to change the laws, and they'll act according to the new laws, because they're such diligent and obedient citizens.

@Stijning

8 жыл бұрын

+panda4247 Well we don't really know that

That was one of the best demonstrations/explanations of HUP I've encountered. Thanks

I really enjoyed the polite discourse at the end! Well done and well presented throughout. Cheers

Love your energy when explaining this concept in your video.

Say my uncertainty principle. You're goddamned right.

I have always struggled with the uncertainty principle, and this is the most awesome thing I've ever seen.

Hey Derek love physics, but this is the simplest and concise best explanation of the uncertainity principle so far , I have watched a lot of your videos love 'em, i am a big fan and will always be, I especially liked the recent one the car which goes faster than the wind.

Answering your question on the demonstration, that is incredible bro!🙌

Wow! I'm studying quantum mechanics at the moment, and this video made Heisenberg's uncertainty principle a lot more understandable.

Fascinating that with a simple mechanical device one can alter quantum probabilities...I would not expect that! Thanks for showing it!

HANDS DOWN THIS IS THE BEST EXPLANATION VIDEO FROM VERITASIUM SO FAR! BRAVO!

I have learned the Heisenberg's Uncertainty Principle with the wave concept. The light wave will be bended on the corners of the slit and if you make the slit smaller, the delta x will get near to the range of the wavelength of the light. So out of the Geometry you can explain and calculate the Interference pattern. But it is nice to see that the Explanation with photons as particles fits as well.

Amazing experience Sir . When we reach the limit where delta x decreases delta p needs to increase to be always greater or equal to h bar divided by 2 . h bar equals plank's constant divided by 2 Pi . This principle is really important . Not only it is important in physics but it expanded to many other domains .

@yashpalsaraswat

3 жыл бұрын

kzread.info/dash/bejne/qmiOlqWfcZifnag.html

if you do it mathematically, you'd find it's not about uncertainty, it really is diffraction.

@lochvids108

7 жыл бұрын

Truth Seeker exactly. its just more 20th century mumbo jumbo. What the fk were the scientists on at this time? was einstein to good for us dod we need some wackos to turn science back to the controlling arms of the churches !

@abdelrahmangamalmahdy

7 жыл бұрын

Light as an EM wave is supposed to be diffracted when the slit size reaches the wavelength of the wave. I(theta) = I(0).sinc^2[bi.d/lamda.sin(theta)] where I(theta) is the intensity of light for a given angle. It is called "single slit diffraction".

@ChrisJaesun

7 жыл бұрын

He mentions that at the very end of the video (3:24)

@abdelrahmangamalmahdy

7 жыл бұрын

oh yeah, thanks for the hint.. I didn't watch the end of the video

@abdelrahmangamalmahdy

7 жыл бұрын

Vinay N.K did you model light as a wave ?

Wonderfully explained! Keep up the great work!

Honestly, I thought that the Heisenberg uncertainty principle had to do with not knowing if the batch was going to produce 99.98 or 99.99 percent purity....

@horsenuggets1018

4 жыл бұрын

I thought it was about the speed and position of a fly

@tiko4621

3 жыл бұрын

shut up, SHUT UP SHUT UP SHUT UP SHUT UP

Isn't this just an example of single slit diffraction ??

@MikeSmith-vb8ul

3 жыл бұрын

Veritasium's videos are sometimes incomplete. Of course there is diffraction, and the smaller the slit and less photons we have coming through the more obvious the diffraction patterns appear

@khayyamaurelius912

3 жыл бұрын

Yes, but if you think about it, the uncertainity principle is a natural consequence of the wave particle duality. If you tried this with electrons, you would get a similiar result because of that.

@suediem9315

3 жыл бұрын

It absolutely is. Somebody need a principle, that's all.

@alextroll3400

2 жыл бұрын

@@MikeSmith-vb8ul It‘s not incomplete. He explains at the end of the video that this phenomena was caused by diffraction.

@MikeSmith-vb8ul

2 жыл бұрын

@@alextroll3400 No -- for full completeness, he would also talk about diffraction more fully and explain all the properties and understanding behind what diffraction is. Obviously, not just only merely slapping a "oh this also could've just been just...'diffraction'. Alright now this video is over!!"

This is also known as the diffraction of light (that proves the wave caracter of light). The lenght of the spot is equal to the wavelenght multiplie by the distance between the slit and the screen divided by the size of the slit. If the slit goes narrower, the lenght of the spot goes wider ! :)

I love how excited he is!

dude u explained it soo well ,for me u really deserve a noble prize

Say my name... "You're Heisenberg..." YOU'RE GODDAMNED RIGHT.

I love the way how u represent light quanta as packets of grouped waves.Like in 2:04.Its actually how they are.

this is by far the most practical way to convey the concept

I cant believe 11 years are over since this video was published, time just flew

"It's the way the world works" Best line ever.

I am so glad i clicked on the video , i never thought of diffraction in this manner

Thank you! This really helped me in understanding about the uncertainty relations.😎😊

Thankyou sir to explain this principle in a very very fantastic way .❤😊

I thought we were going to see how to cook meth.

@ManyThings26

10 жыл бұрын

that's quite the same thing to physicians !

@Tesla_Death_Ray

10 жыл бұрын

David Lecaille You mean physicists, but should have said chemists

@makaimesa3893

10 жыл бұрын

why.

@Tesla_Death_Ray

10 жыл бұрын

Makai Mesa Heisenberg is the alias of a character on a popular tv show about methamphetamine production

@NickPershyn

9 жыл бұрын

butterflycaught900 And he was teaching chemistry.

Light behave like both particles and waves that is why widening of the beam is caused by both diffraction and uncertainty in momentum. Diffraction because light behaves as wave and uncertainty in momentum because light is a particle.

@aaronsmith6632

5 жыл бұрын

Yes exactly, they are just two different perspectives which result in the same conclusion.

Hey Derek, love you work. Fellow aussie engineer/backyard physicist here. Wait a minute, there are some things that don't make sense here: 1) If the light is effectively bending outwards (similar to what happens in dispersion) what is going on here, what causes the light to bend and change direction? In dispersion, it is that different wavelengths have different apparent speed in the glass prism and thus refract at greater degrees, what is causing it to happen here? 2) Do the photons change direction because classically (p=mv) relativistic mass of light cannot change? only the velocity made up of c and direction can. Since everything else is constant, only the direction can change? 3) But the momentum of light according to de-broglies relation (p=h/λ) for p to increase the wavelength must be decreasing (i.e frequency increases). Is this occurring? If we were to put a detector on the other sided of the slit would we notice higher frequency photons being emitted? 4)When I created my own single and double slit experiments I always thought this was occurring due to diffraction as the light bent around the edges of the slit?

I can't imagine that I finally understood uncertainty principal. Thank You So much.

"I've gotta say a big thank you to professor Walter...White"

Cop: "Sir, I pulled you over for speeding. Do you know how fast you were going?" Citizen: "No officer, but I do know exactly where I am."

@sc-ek6qz

6 жыл бұрын

Walks in front of cop car with hands together like a monk and walks on by... ..

@jay-tbl

5 жыл бұрын

You stole this from top comment lol

@AmmoBops

4 жыл бұрын

rentacow this joke makes no sense Or maybe I don’t obtain the knowledge to Find the humor in this puzzle

@officialspock

4 жыл бұрын

@@AmmoBops same, lmk when you get this joke

@AmmoBops

4 жыл бұрын

spock still don’t get the joke 😂 it’s all good tho

That is an incredible demostration of the principle at work

well this teacher is so energetic, it never make us feel bored.

I've studied Quantum Mechanics for 6 years now, never have I come across a better explanation of the Uncertainty Principle. On behalf of the human race, thank you Derek.

By my guesses and partially calculated thoughts,. I believe the hiesenburg uncertainty principle can be directly related and compared to many things in life, for example, human thoughts on a given situation.. or the amount of traffic at a given junction when driving at a certain time of day, the estimated amount of fish in a river and countless other situations and circumstances.. I consider it to be a basic fact of life now.. along with the law of un-intended consequences..

@watamatafoyu

Жыл бұрын

Macro objects don't work that way.

Thanks a lot, I never understood uncertainty principal this better before :)

The great Walter Lewin . You're not alone. I also have gratitude to this incredible man.

hey Dr. Muller, I'm working on a project o Quantum Physics? i have one question. How can we find the width of slit (uncertainty in x) when uncertainty in momentum increses?

You're Goddamn Right!

So good explanation, makes u feel like a genius. Thank you, this helped me alot

Thanks for making the most didactic video about this topic that I've ever seen!

Isn't this just the diffraction you get when you send light through a small aperture? Also, how does changing the momentum result in the widening light projection if the light is from a laser (therefore straight)? I thought an increased uncertainty in position would result in this pattern. Please help me understand.

@dhichicpop2531

2 жыл бұрын

Basically momentum is a vector quantity = mv. Here the mass of the photons cannot change. Their speed in a medium( air) also cannot change. So the only thing that can change such that momentum changes is the direction of the vector

@TylerUchiha

Жыл бұрын

You're correct, it is the same diffraction you get from placing a laser beam through a small aperture. When the beam of light spreads due to diffraction, it loses coherence - it becomes less focused. The aperture would be the distance between the two slits - this distance is what influences the uncertainty of the position of the photons. The smaller the aperture, the less uncertainty we'd have in knowing the position of the photons because the light beam has to fit into a smaller slit. This is where it becomes very unintuitive. The calculation you saw in the video, (deltaX)(deltaP) >/= h/u X Pi is the uncertainty relation - it's compendiously a constant of the universe in a mathematical expression, think of it like balancing colours of paint to produce a certain colour. You may have to decrease the intensity of one colour to make another colour more apparent. Also, changing the momentum results in a wider and more diffracted light beam because the momentum is tied to the direction of the light beam photons. Momentum is a vector quantity - it has direction and magnitude. The momentum would change and in turn the direction, so as to balance Heisenberg's uncertainty relation. Don't forget that the uncertainty/focus of the momentum increases when the uncertainty of the position decreases. The shape of the light on the walls is related more to the momentum as the momentum determines the destination of the light beam, remember what I mentioned about direction.

Where are the Breaking Bad jokes?

@nischay4719

7 жыл бұрын

terrysarmy2695 but i am watching this as a infotainment :p

@mickelodiansurname9578

7 жыл бұрын

terrysarmy2695 ahh... its 5 months later now... so did you get a pass?

Exactly at the start of video I was thinking that why doesn't he take account of diffraction.Thanks for clarifying at the end

It can also be looked as diffraction through a single slit. As we decrease the size of slit it gets comparable to the size of wavelength of light and light bends at the corners (showing wave nature) entering the shadow region and making a way between illuminated and shadow region through dark and bright fringes.

this experiment seems so perfect and easy but I'm afraid every other person on this planet would have been a physicist if physics and nature were that simple...... what I mean is...nature doesn't work the way it does to NOT break OUR laws...instead we make laws to describe nature's nature! so what you said wasn't convincing enough.... I really like your videos and expect the RIGHT explanation for this so very complicated phenomenon soon....thnx! :)

I came here to find breaking bad jokes and was not disappointed

I'm a visual learner, so I liked the video graphics you have, much better way for me to learn. Dr. Dorian Canelas at Duke Univ has a link to you from the Intro to Chem course on Coursera. Glad she gave us student this link!

Again: very good explanation. Makes deeper sense!

If people accepted Heisenberg uncertainty principle based on this experiment, then people were/are weird. Let me explain, before making the slit narrower, a lot of photons were going straight but a lot of them were already going to the right and left.But this was not very clear initially. Now when the slit was made narrower and narrower, the photons which were going to the right and left started bouncing of the sides of the slit and changed their momentum and started moving to the center. This increased the brightness at the center . This is why we see many more bright lines and spots appearing at the center when the slit was narrowing down. When the slit was even more narrowed down ,less number of photons passed through the slit and so the brightness decreased.Also , the photons that are now capable of passing through the slit had more chances of hitting the sides of the slit because the slits were very close enough. So now more photons were hitting the sides and changing their momentum , almost 90% of them. So they were spreading out more and so the brightness at the center decreases more and more. Of course the bouncing to such a degree that the particles bouncing from the left side are interacting with the particles bouncing from the right side and creating crest and troughs pretty far away from the center. Its particle physics ..not an uncertainty principle. Stupid for all the people who can't think in the right way and believe everything blindly.

@NickPershyn

9 жыл бұрын

Wow, man. You are actually really really wrong. Let me explain why: 1) The same thing happens when "sides" are sharp, and there just no place for photons to bounce. 2) The material of the slit could be black, so photons just get absorbed instead of bouncing. 3) How would you explain experiments with black disk that creates white spot behind it? You can't! 4) What do you think happens whet you reflect a laser beam from diffraction grating? Just go and check you yourself!!! 5) What pattern would monochromatic light create if it goes through a long waveguide? Make a prediction and see for yourself what happens in OUR world! Do you really think your primitive hypothesizes haven't been checked and disproved already??? You'd better checked yourself before calling someone stupid! Current physics theory not only explains everything ordinary human can encounter, it is also so simple and easy that even you can understand it if you want to. P.S. I as a physicist have rechecked every single thing while was studying, trust me, the current theory we have IS the most logical, simple and intuitive explanation! There were so much different experiments with different quantities, materials, shapes, details, so I am pretty sure I can name an experiment that can prove you wrong in any way, if your theory is simpler that quantum mechanics. Did you heard about tunneling effect? How would you think reflectionless surfaces work? With this primitive concept of bouncing photon particles so many things in this world shouldn't work, so I can't even imagine how in this universe you could come up with such an absurd idea...

@yashkesari

9 жыл бұрын

Nick Pershyn 1) No matter how sharp the sides are , photon are just too small and for them the sides will mostly remain big enough. 2) Who says that all the photons are absorbed by black color. Light can only be absorbed completely in a black hole, not in a black sheet , or anything which is painted black or any material which is black. 3) Same reason as above. 4)I will check and come back 5) I will check and come back. And yes I am talking about OUR world.....where all black colors are not black holes.

@yashkesari

9 жыл бұрын

Nick Pershyn Try this experiment.Take a glass of water and keep a board on the floor with a narrow slit in it.Then slowly throw the water towards the slit. The water will come out from the other side and spread itself. It will not move in a narrow straight line after coming out from the other side. Also, if the same experiment is done with a tunnel the same result will be seen... and water is seriously a group of particle , not wave... light behaves in the same way.

@iNotFound

9 жыл бұрын

yash kesari water is not the same as electromagnetic waves.

@yashkesari

9 жыл бұрын

Heisenberg's uncertainty Principle is applicable to both particles and waves.

Good video!

I also did the experiment when I was in my Undergraduate studies. It was an incredible experience.

Sir,Walter Lewin Rocks Here also! Helping me lot in preparation of my Jee exams!❤️

Hi, doesn't the image actually gets wider because of the diffraction ? Because we did a very similar experience in science class by calculating the wavelength of the laser using the length of the image on the wall and some formulas... But our teacher says it has nothing to do with Heisenberg uncertainty principle and only illustrates the diffraction of light. We used 160nm wide holes and green lasers with a wavelength of 532nm

It's a single slit experiment much like youngs double slit experiment. All you need is a coherent beam of light which is Laser.

U just made the concept clear. Salute to you

I am a physicist specializing in optics. The problem with the Heisenberg Uncertainty Principle is that it is so robust that it can be used improperly and you'll still get a good qualitative/quantitative estimate for a phenomena. The effect he's showing is the single-slit experiment which has to do with interference effects of the wavefront of the light. The Uncertainty Principle basically says that a wavepacket constructed using Fourier optics has some intrinsic width, dx, with some distribution of wavevectors with an estimated FWHM of dp. As dx goes to infinity, you have no knowledge of when the wave started or where, but you do know its wavevector with absolute certainty. As dx gets smaller and smaller, the FWHM of the wavectors that construct it gets broader and broader based purely on how Fourier transform properties work. The absolute limit of how sharp you can get dp for a given dx is given by \hbar/2. Interestingly, creation and annihilation operators in quantum mechanics are constructed using this principle. The combination of creation and annihilation operators are responsible for the addition or subtraction of quanta of energy from waves. This is where we get the "particle" nature of light from. So, in reality, the particle nature of light is a direct manifestation of the wave properties of light. It seems a bit paradoxical until you consider that all beams of light must be finite and you need to consider what happens at the boundaries of the beam.

Yes, but..., how do i make meth?

So Heisenberg is driving one evening and he gets pulled over by a policeman. The policeman says 'Do you know how fast you were going?' Heisenberg says 'No, but I know where I am.'

@vibodhj349

5 жыл бұрын

So Heisenberg was driving a vehicle..., Yeah, Yeah I know the joke.

this video helped me understand a whole chapter of Quantum Electrodynamics by Feynman. I was confused on it until now

Cruising through the internet to find the explaination that i will understand, always finishes on one of your videos. Thanks!

The Heisenberg Uncertainty principle says we can't know both the position and the momentum of a quantum particle. My question is this, if you know that a photon is going the speed of light, the momentum, then does that mean you can never know the position of the photon?

@erikdk321

7 жыл бұрын

No, you can't know what direction a particle is going, you can know the momentum.

@TomHendricksMusea

7 жыл бұрын

Strange, so when it comes to photons, we don't know anything about direction - even in the two slit experiment. How do we know they are going through the slit instead of around it or coming from behind?

@erikdk321

7 жыл бұрын

Tom Hendricks We know they are going through the slit because we can see it and because there would be no reason for them to just suddenly go in another direction, until they passed the slit.

@TomHendricksMusea

7 жыл бұрын

But they are outside of time, so they have forever to get back there. That seems logical, and mine seems silly, but they both fit the facts. And when you see, you change the outcome too don't you?

@erikdk321

7 жыл бұрын

Tom Hendricks wut?

When you stop down your apature on your DSLR (f.ex) to something like f/22, you'll get less sharp images because of "diffraction" (as photography-tutorials always say). But is this also because of Heisenberg's uncertainty principle?

@amanganeju7904

6 жыл бұрын

No, it isnot. increasing the f value rather increses the sharpness.

@JimCullen

6 жыл бұрын

Increasing the f value doesn't increase "sharpness", it increases depth of field, which means a larger portion of the photo is in focus. But what +overTIMe is talking about is something different. When you stop down really far you start to get diffraction which can reduce the sharpness of your image somewhat. The effect is fairly minor though, and even at extreme crops it can be difficult to notice.

Just loved it , will surely mention you and your effort once I do somethig really big 😊😊

dammiit i love you after seeing like 7 different videos in youtube you finally helped me get it

What's the *cause* of the principle, though? That's something I really wanna know...

@adamwilkinson4264

9 жыл бұрын

There is no cause. It's simply how the world works, in the same way that gravity pulls you down, and electrons are negatively charged

@MinecraftxFan1995

9 жыл бұрын

Adam Wilkinson I'm sorry... Forgive me or feeling that's not good enough. Cause and Effect is a big part of science. Why should some principles get exceptions just because we can't explain them yet?

@adamwilkinson4264

9 жыл бұрын

something Because the Uncertainty principle IS the cause

@MinecraftxFan1995

9 жыл бұрын

the Heisenberg uncertainty principle is the cause of the Heisenberg uncertainty principle. Is that what you're saying?

@adamwilkinson4264

9 жыл бұрын

something Kind of, I'm saying that it simply is one of the fundamental things that makes the universe work, it doesn't have a cause, in the same way that magnetic forces/attractions have no real cause when you get down to it, and as well as why you can't walk through walls.

Does it really need to be explained by the Heisenberg's uncertainty principle? isn't it just simply how waves bend around corners? the result of passing a light through a small slit is due to diffraction and possibly creating a interference pattern.

@nikolasc1594

8 жыл бұрын

Shanghai Alice I've always hated this explanation, the uncertainty principle seems to be a confused perception of diffraction. That's just me, I also don't like photonic theory, I have yet to see an explanation or experiment which convincingly shows that light can travel as particles, it really bothers me.

@brunorhagalcus6132

8 жыл бұрын

Shanghai Alice That is a great deduction and one that was contemplated; however, the wave pattern occurs even if a photon/atom/low atom count molecule (so far)/etc. is shot one at a time towards both slits. This means something that was a particle turns into a wave goes through both slits and interferes with itself. The uncertainty principle engages again when a detector is added to discover which slit the particle went through. The wave function then collapses back into a particle. This doesn't mean something emitted from the detector hits the particle. If this were the case the particle would go shooting off in all directions and not create the clump pattern. The source and particle become entangled forcing the wave function to collapse. I would suggest researching wave particle duality, superposition, quantum entanglement, wave function collapse, the quantum measurement problem and delayed choice quantum eraser (which was recently confirmed). These will help you understand why it isn't diffraction. Well, maybe not understand, but at least learn to accept this wacky stuff is real. lol. Quantum Theory obviously isn't complete, but it is one of the most successful and thoroughly tested theories in the history of science.

@paulgibby6932

8 жыл бұрын

Bruno Rhagalcus thanks for this answer. What is a "wave" anyway? What is a "particle"? Categories?

@brunorhagalcus6132

8 жыл бұрын

Paul Gibby Seriously, maybe you can answer for me why Google deletes my paragraph delineations. What a pain. Anyway, hi Paul! Thank you so much and you're welcome! ok, I can already tell you this is going to be long, but I hope it helps. There are categories, but they are a little different than what you're asking I think. I'm going to assume you mean "wave" as it pertains to wave function in Quantum Mechanics (QM). There isn't really an argument in QM about the realness of a particle. It's more of an epistemic (system of knowledge) as opposed to an ontic (physically real) categorization in relation to wave function and its collapse. Epistemic in QM is sort of like saying the equations of QM are basically as real as a molecule. The ontic means the wave function/collapse is real and not just an epistemic probability wave. The ontic (wave function is real) interpretation has been verified recently as being most likely. I'm going to attempt to analogize wave function and collapse as much as possible in a classical fashion. The following are simply to help increase the level of understanding of QM's counterintuitiveness and not for exactness. Imagine a roulette wheel Superposition: not to be confused with supperposition which is where you sit to eat dinner, lol jk. Anyway, imagine the roulette wheel. You take a picture of the ball in each of its possible locations (number slots) on the wheel...including not on the wheel at all. Now, ignore the wheel for a moment. The pictures now become the wave function and represent the superposition of all the possible positions (number slots) that the specific ball can reside on the wheel. Entanglement: You then choose a specific picture which creates a link between you and the pic. This can't be explained classically. This link basically makes you and the pic one spatially/time irrelevant system. Collapsing the wave function: Now that you've chosen a pic and entangled (linked) yourself to it, the picture collapses into the ball and the ball appears in the respective number position on the actual table. When you chose a pic (collapsing the wave function), the other pics disappear because all the pics represented the same ball in the first place. Now, you have a physical location for the ball. I must digress a little...the probability distribution isn't at equal odds as it is for a roulette wheel...meaning you have equal odds of landing on any number on the wheel, but not with the quantum wave function. It's like non-arbitrarily adding more pictures of a certain number which increases the odds you will choose that number. Quantum tunneling: Say there is a physical barrier across half of the roulette wheel and it isn't spinnable. The ball as a particle can't, with realistic odds, get through the barrier to lie on the other 1/2 of the wheel. Well, you already have the pictures showing the ball in all possible states (the wave function). YOu repeat the same steps as in the superposition example. Choose a pic (collapse the wave function) and the ball appears on the respective number on the actual wheel. The barrier played no role because the pictures (wave function) made the barrier irrelevant and allowed you to pick a picture irrespectively. This example is why fusion on the sun is at much cooler temps than it takes us to produce it here on Earth. Replace the ball with a proton, make the barrier and 1/2 of the wheel a hydrogen nucleus, take the superposition pics (pics of the ball in every location), choose a pic (collapse the wave function), then the ball (proton) snaps into position on the respective number on the actual wheel. There is a possibility the picture you chose reveals the ball (proton) on the 1/2 half of the wheel that is within the hydrogen nucleus and voila, you have QT fusion without disrupting the hydrogen's strong force field (the barrier on the wheel). There are so many things that can be questioned in these analogies. My intent was merely to give you a foundation, so it isn't as difficult to alter your mind to the counterintuitiveness as you learn more about QM. Sorry for my verbosity and surely a lot of misdirection from my examples.

@paulgibby6932

8 жыл бұрын

Thanks Bruno (I like the joke too :)). It will take me some time to digest. I would like to be able to apply this explanation to my own perception that sometimes when I wake up to a noise or external stimulus, my dream seems to end at just that time (with just that noise, usually. e.g. in dream, a gunshot, in external world, a door slam). So that I think the brain constructs events backwards in an instant. Of course this may seem to have little to do with your explanation. But long live the investigation(s)! Thanks again

This is a great explanation..thanks for sharing...

I'm glad you got better at explaining stuff. This was fluffy

hi what is the difference between this and diffraction. are they both the same?

@SkizzlePiano

7 жыл бұрын

the uncertainty principle causes diffraction, it also applies to other things tho

@wxh2018

7 жыл бұрын

SkizzlePiano oh i see thank you

@mikaeljensen4399

7 жыл бұрын

In no way does the uncertainty principle cause diffraction. Diffraction is a wave behaviour. Uncertainty is just uncertainty and in quantum mechanics it is about the failure of operator to commute; or more precisely about the fact that no quantum mechanical state can have shared eigenstates (of definite value for some operator) for two operators which do not commute. So the lower limit of the uncertainty is proportional to the expectation value of the commutator.

@fandomguy8025

5 жыл бұрын

Mikael Jensen, No it's that particles have wave behavior. And it's simply due to Fourier transforming a matter wave.

Scientist: Do you understand? Me: Well yes, but actually no

This phenomena is actually Diffraction which is explained on the basis of wave nature of light and not particle nature. But this guy gave a whole new aspect to thinking about it . Good !!!

What an enthusiasm is teaching! well done

this may be explained through diffraction also

@pathikghugare

4 жыл бұрын

??

@nauka7565

3 жыл бұрын

Yeah

@khayyamaurelius912

3 жыл бұрын

Because it IS diffraction. This happens because particles have a wave-particle duality. When the slit becomes smaller than the particle's wavelength, you decrease the uncertainity in position, but the uncertainity in momentum goes up.

So basically it's like water through a hose the smaller the hole the more it's sprays/mists because it's being forced through a smaller space.

@lochvids108

7 жыл бұрын

J Lann exactly.

@wildedibleplantsofthemedit8676

6 жыл бұрын

Nothing like that :p

@vibodhj349

5 жыл бұрын

I was thinking about this same analogy. But then, how can it relate to the uncertainty principle in which the h value is very small 1 divided by 1 followed by 34 zeros?

thanks a lot.. u helped me to understand uncertainty principle very well.

best explanation of Heisenberg's principle I wish you were my physics teacher