Sir you have not questioned anything of basic principles of physics that's reason you can't break it start questioning everything of physics theory you would know that physics what is being taught is bunch of lies and deceit hope you would not offended by my opinion 🙏🙏🙏
@@nikis7742nobody in the world understands quantum mechanics in very simple everyday terms. The whole theory is a mathematical construct, we have no clue of its deep meaning. So I wouldn't say the teacher understands less compared to the guy in the video.
Yes, but he is talking about the uncertainty of a single quantity. And it's F-transform. But the uncertainty principle is about the product of two things position*momentum. Not position alone, and not momentum alone.
@@joeboxter3635 No, you are wrong. He literally said it in the video: the momentum is the Fourier transform of position. So the uncertainty principle is not talking about "two separate quantities," but rather, it is indeed talking about a quantity and its Fourier transform. In fact, this how conjugate variables are defined.
6:06 I've waited so long for somebody to actually say this. My classmates still think that the Uncertainty Principle is a result of our "Technological Impotence". This video is a good proof I can put forward...... Thanks a ton man.😊😊😊
My God. You have clarified, uncertainty principle and Fourier transform in one go!!! The world needs more teachers like you. Thanks for the really simple and lucid explanation.
Great video! In uni, when I realized how "wide in real space" gives "narrow in Fourier space" and how this physically ties to the uncertainty principle - I think that was really when quantum mechanics got REALLY cool. Excellent intuitive explanation. Feynman would be proud.
I’ve a compute engineering degree so I’m familiar with Fourier Transforms. And I have to say you did a beautiful job describing the simple concept behind them while leaving out the intricacies communicated by the specific mathematics
I was hopeless at maths at secondary school. So bad, in fact, that I was relegated to arithmetic class. Now, over 55 years later, I am still hopeless at maths. Fortunately, I have an interest in astronomy and science, which is steeped in maths. A lot of the subjects you bring up are fundamental to hard science and I enjoy being able to finally grasp what I am missing out on. Keep up the very good work you are doing. Physics looks like a blast once you can figure out its tools. Where was your method of explanation when I was a lad?
Einstein wasn’t very good at math either. Almost failed in elementary school math. I understand that he had his wife or someone else go over his math for completeness and accuracy.
Dude , Einstein was a genius, at math Masterd diffirential calculas by the age of 15 The only reason he was not good at maths in school was because he didn't agree with a lot of things taught at the time
You must check out 3Blue1Brown's channel here on TH-cam! Trust me, his explanations are a treat!💎
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More often than not I find it hard to fully comprehend subjects explained in your videos. I get the message. Most if not all the logic behind it. But due to deficiencies in my educational background and lack of any scientific experience I often fail at math or physics. Yet I find myself trying and rewinding your videos. Your explanations seem so approachable, that I always have an impression that with some extra effort (and enough replays), "I'll be there with you". Thank you for your work-is truly appreciated.
What I've always wondered, is WHY momentum is the Fourier Transform of position, and WHY position is the Fourier Transform of momentum. That part I don't understand, but I'll continue to look for an answer.
Well, maybe in some moment in your life, I don't known, in your school or college, you studied or will study a particular kind of waves, the harmonics waves. They have a perfect sinusoidal shape and are expressed by the following formula: y(x,t)=Acos(kx-ωt) Where A is the Amplitude, k is the wavenumber and ω is angular frequency. But we can rewrite it using some identities: k=2π/λ and ω=2πf, where λ is the waveleght and f is the frequency. So y(x,t)=Acos(2π(x/λ-ft) If you notice, there is an special relation in this equation beetwen time (t) e frequency (f), they are being multiplied. Ideed, time and frequency are conjugate varibles when we are dealing with processing signs transported by electromagnetic waves. Is a consequence of the mathematic area of Fourier Analyze that when you are measuring the uncertanty of time and frequency, you need to respect an analagous inequality ΔfΔt≥1/4π (The uncertainty principle is: ΔxΔp≥h/4π=ħ/2 where ħ=h/2π) Fantastic, no? So, you must be questioning about the uncertanty principle and why position and momentum are conjugate variables. Well, I will not be able to demonstrate anything, but I can show that the pattern of t and f in the harmonic wave repeat for p and x. How? Quantum mechanics is a kind of undulatory mechanics, and a free particle solution for Schrodinger`s equation can be at leat in it`s real part be represent by the same shape of harmonic waves: Ψ(x,t)=Ψ_0cos(2π(x/λ-ft) But particles in quantum mechanics follow the Broglie's relations, every particle behave like a wave and have a wavelengh, and his relation with momentum is given by: p=h/λ, where h is the Planck's Constant = 6.62607004 × 10-34 m2 kg/s So, if you want, rewriting the solucion of Schrodinger's Equation Ψ(x,t)=Ψ_0cos(2π(px/h-ft) p and x are simetrically together in the solution, like t and f. This is because they are profoundly related to each other. I think this is not the final response for your doubt, but I think can confort some curiosity crise. Lol See ya!
Gustavo de Oliveira Thank you Gustavo, I truly appreciate your efforts and share your knowledge here. I really found this informative. Thank you, God bless.
@@027_manishdixit7 Saying they are conjugate variables means nothing. It is like defining integration as the inverse of differentiation. Nobody cares what a variable is. Nobody cares what conjugate means. The question is clear and appropriate: Why are position and momentum the FT of each other? Actually it is more. appropriate to ask why certain "pairs" are so linked. And not the simplistic answer that momentum depends on wavelength and position depends on distance. Why aren''t wave number and angular frequency also paired?
It would help to know how the Heisenberg Principle was originally derived. Was it from the Schrodinger equation? If you've found out or ever find out, let me know.
I have seen heisenberg uncertainty formulas for years. But after this explanation meaning of heisenberg uncertainty is certainty meaning in terms of what this formula is telling. 👏👏👏
The explanation of the link between the Fourier transforms and the Uncertainty Principle made a lot of things clear as to how this principle is in effect. Thanks, man.
I watched Up and Atom's video on the uncertainty principle where she gave the compromising the measurement of position vs compromising the measurement of velocity explanation in terms of firing a photon with more or less energy and how much that will knock off the electron and my mind was blown by finally finding an intuitive explanation. But I immediately thought that seemed more like a limitation of the technology we have to measure than a property of the electron itself.... And right after I watched your video and my mind was de-blown and re-blown all over again just like that! haha great video!!
This is the best explanation of uncertainty principle so far! After having seeing several videos. It is understandable especially you have a STEM degree but still want to learn more about the basic physics theory.
What the hell bro seriously this is the best explanation i ever herd or veiw all about Heisenberg uncertainty principle 💯..... Brø ¡ appreciate your work🙏 you are just awesome! ☺️
Simply fantastic Partha ! Nowhere else I could find such beautiful, easy to understand, way of explaining Heisenberg uncertainty principle but also Fourier transformation. God bless you.
The way you explained this topic was easy to understand for a CA student. I was stucked into this topic while reading Stephen hawking book brief history of time . Thanks parth
People always say there's no way of getting around to things that are hard, until a true genius is born. I am sure that we will have better understanding of quantum mechanics in future. Current definitions and theory are based on partial understanding.
I,m just glad to find someone else that's happy that the uncertainty principle is just "because maths" and doesn't like the explanation about position observations making photons bounce off particles and change the particle momentum. That alternative explanation is (as you see in the comments) just asking for people to create Heath Robinson equipment that will measure position and momentum at the same time and violate the principle.
The Heisenberg Uncertainty principle is not about our inability to measure the position and momentum in experiments, but about their actual values, which may or may not be measured in an experiment, and this is made clear using the Pilot Wave interpretation of Quantum Mechanics, which interprets the ∆ differently from the other interpretations in Quantum Mechanics. Whereas the other interpretations say ∆ corresponds to a random distribution with a range, Pilot Wave theory assumes ∆ has a Gausian distribution for the range, but with an average value in the middle. Here is derivation of the relation: ∆f ∆wavelength >= c directly from the Heisenberg Uncertainty Principle (HUP), where f is the frequency, and c is the speed of light: ∆x ∆p >= h. But for a wave ∆x corresponds to ∆wavelength. From quantum mechanics, ∆p=h/∆wavelength = h∆f/c, since wavelength x f =c, or ∆wavelength = c/∆f. So inserting ∆x=∆wavelength and ∆p= h∆f/c into HUP yields: ∆f ∆wavelength >= c. Using this relation, and using the interpretation from Pilot Wave theory, where the ∆ correspond to a range of values with an average. Then if light is emitted from a source, where the frequency (f) is known, then near the source the wavelength is completely unknown due to Fourier theory, thus ∆wavelength=infinity. Consequently the speed of light is infinite very near the source. But after propagating about one wavelength from the source, according to Fourier theory, ∆wavelength becomes approximately equal to the wavelength, and thus the speed of light is approximately c. At extreme astronomical distances from the source, according to Fourier theory, ∆wavelength never becomes exactly equal to the wavelength. So the speed of light never becomes exactly c. The speed of light is not a constant as once thought, and this has also been proved by Electrodynamic theory and by Experiments done by many independent researchers. The results clearly show that light propagates instantaneously when it is created by a source, and reduces to approximately the speed of light in the farfield, about one wavelength from the source, and never becomes equal to exactly c. This corresponds the phase speed, group speed, and information speed. Any theory assuming the speed of light is a constant, such as Special Relativity and General Relativity are wrong, and it has implications to Quantum theories as well. So this fact about the speed of light affects all of Modern Physics. Often it is stated that Relativity has been verified by so many experiments, how can it be wrong. Well no experiment can prove a theory, and can only provide evidence that a theory is correct. But one experiment can absolutely disprove a theory, and the new speed of light experiments proving the speed of light is not a constant is such a proof. So what does it mean? Well a derivation of Relativity using instantaneous nearfield light yields Galilean Relativity. This can easily seen by inserting c=infinity into the Lorentz Transform, yielding the GalileanTransform, where time is the same in all inertial frames. So a moving object observed with instantaneous nearfield light will yield no Relativistic effects, whereas by changing the frequency of the light such that farfield light is used will observe Relativistic effects. But since time and space are real and independent of the frequency of light used to measure its effects, then one must conclude the effects of Relativity are just an optical illusion. Since General Relativity is based on Special Relativity, then it has the same problem. A better theory of Gravity is Gravitoelectromagnetism which assumes gravity can be mathematically described by 4 Maxwell equations, similar to to those of electromagnetic theory. It is well known that General Relativity reduces to Gravitoelectromagnetism for weak fields, which is all that we observe. Using this theory, analysis of an oscillating mass yields a wave equation set equal to a source term. Analysis of this equation shows that the phase speed, group speed, and information speed are instantaneous in the nearfield and reduce to the speed of light in the farfield. This theory then accounts for all the observed gravitational effects including instantaneous nearfield and the speed of light farfield. The main difference is that this theory is a field theory, and not a geometrical theory like General Relativity. Because it is a field theory, Gravity can be then be quantized as the Graviton. Lastly it should be mentioned that this research shows that the Pilot Wave interpretation of Quantum Mechanics can no longer be criticized for requiring instantaneous interaction of the pilot wave, thereby violating Relativity. It should also be noted that nearfield electromagnetic fields can be explained by quantum mechanics using the Pilot Wave interpretation of quantum mechanics and the Heisenberg uncertainty principle (HUP), where Δx and Δp are interpreted as averages, and not the uncertainty in the values as in other interpretations of quantum mechanics. So in HUP: Δx Δp = h, where Δp=mΔv, and m is an effective mass due to momentum, thus HUP becomes: Δx Δv = h/m. In the nearfield where the field is created, Δx=0, therefore Δv=infinity. In the farfield, HUP: Δx Δp = h, where p = h/λ. HUP then becomes: Δx h/λ = h, or Δx=λ. Also in the farfield HUP becomes: λmΔv=h, thus Δv=h/(mλ). Since p=h/λ, then Δv=p/m. Also since p=mc, then Δv=c. So in summary, in the nearfield Δv=infinity, and in the farfield Δv=c, where Δv is the average velocity of the photon according to Pilot Wave theory. Consequently the Pilot wave interpretation should become the preferred interpretation of Quantum Mechanics. It should also be noted that this argument can be applied to all fields, including the graviton. Hence all fields should exhibit instantaneous nearfield and speed c farfield behavior, and this can explain the non-local effects observed in quantum entangled particles. *TH-cam presentation of above arguments: th-cam.com/video/sePdJ7vSQvQ/w-d-xo.html *More extensive paper for the above arguments: William D. Walker and Dag Stranneby, A New Interpretation of Relativity, 2023: vixra.org/abs/2309.0145 *Electromagnetic pulse experiment paper: www.techrxiv.org/doi/full/10.36227/techrxiv.170862178.82175798/v1 Dr. William Walker - PhD in physics from ETH Zurich, 1997
6:06 I was waiting for this. Many a people have wrong info about the uncertainty principle. However this explanation is also stated in the " Brief history of time" by hawkings.
Yes . Your channel is growing fast and I'm truly happy for that. Your channel is underrated . You deserve much much attention . I try to spread your channel as much as i can in my college ! Thanku your videos makes me happy . I'm a dropout physics student , you make me fall in love with physics again . (I'm currently doing engineering and your topics are in my syllabus)
OK, so after watching a bunch of your brilliant videos, one thing is for certain: your videos simply are not to be watched at 1.5x speed. A rush of information so well presented and explained. Thank you Parth! :)
I watch them at 0.75 x! It is tough to keep up else. You keep thinking as he speaks and if you watch it on higher speed then the thinking interferes with the listening!
"If a quantum particles position would be completely known, the momentum would be totally unknown". I actually think this makes sense also in the macro world. If a bullet position is completely known and fixed in space, meaning there is no time interval to measure its movement from one position to another, its momentum / velocity can not be measured / calculated. If there IS a time interval between two positions, allowing the calculation of velocity / momentum, then the position is not fixed in space.
I'm an oddity in the world of physics instructors. I'm a Cherokee American combat veteran,who taught physics to advanced science students. I used a significant amount of humor in my lesson plans because I read a number of articles explaining that people kept ideas they heard while laughing more deeply embedded in their memories. Now, to address your exquisite explanation of the Heisenberg Uncertainty Principle. Actually, I don't think I could have expressed it any better than I just did. Your presentation was simply perfect. Very well done indeed. Now, it's my turn to instruct you in my language. Wado means thank you and Udo means Brother. Wado Udo! 🪶🪶🪶🪶👍🏻🤘😎
I like your presentations a lot because you put aside math, because math can never ever explain anything, but only describing something with precision ... But your talk do also only describe Heisenberg's uncertainty principle. You answered the WHAT it is question, but not the WHY it exist in nature question ...
Dear Parth, Could you do a video on the maths which gets applied in Physics. May be a few series. Fourier transforms, Divergence, Partial differential eqns, etc. It would be useful. You explanations are really great and easy to understand. But physicists also require a little mathematics brush-up. Thanks. Kiran
Parth will I'm sure get round ot it. Meantime check out the math explanations given on TH-cam by 3brown1blue. They're clear, visually very well illustrated, and are very helpful.
Your explanations are really top notch... Heisenberg principle is a double-edged sword, but necessary given the Measurement Problem. It allows wishy-washy systems to be pinned down to a known error range, thus limiting - but not stopping - compound of errors... It also hides lots of fuzzy details and gives up on the notion of determining them. The problem is, the universe has to be deterministic deep down, or it couldn't exist. If you deny this you might as well believe in God, The Controller as well as Creator... MAGIC is not an option to proper physicists. -- We may not be able to measure to multiple factors at once to a high enough resolution, so cannot discover deeper workings using Science (alone), it requires deduction, reasoning and leaps of faith... This is why Science is stuck in a fundamental rut.. Still, accuracy of measurement has improved on small enough scales to implement basic quantum computers. We don't really need a fully deterministic REAL unified field theory in practical reality but it would be nice to have one.
As a lecture demonstration, I used to use a storage oscilloscope, a tuning fork, and a microphone. The tuning fork Produced a nice clean wave with well defined frequency but very poorly defined duration... I then blank the oscilloscope, and clap my hands. That produced an irregular wave form totally indeterminate in frequency but very sharply defined in time.
I agree. 2 for one. Imagine electrical engineering or system engineering with out fourier transforms and quantum physics without uncertainty principle.
The bit about momentum being related to position by Fourier transformation threw me, you passed it over quite quickly as if 'everyone ' knew that. Having looked into it it certainly makes sense now. I see that some define Conjugate variables based on this dualism. I am not sure that it has always been. I think that I am supposing that there is something more fundamental than the simple fact that they are Fourier Transforms of each other.
He probably didn't get into it because it involves a little linear algebra. The position and moment are not just a number as he mentioned, they are a operators. If two operators commute then x * y = y * x. If they do not commute then x * y does not = y * x. In our case "momentum space" and "position space" do not commute so if you perform a Fourier Transform to go from position space to momentum space you end up with this hbar/2 term he discusses. This is how I think of the uncertainty principle. It's true of any non commuting operator, but you don't have the hbar term because it's not quantum mechanics.
@@zacharywarner1806 Sorry but that is a load of bollux. Somewhere in that mish mash might be a kernel of truth but the way you have described it makes not one iota of sense. It is also stuff all to do with linear algebra although I do understand that Quantum Theory can be described thus under The Copenhagen Agreement where by Hermitian operators define what can actually be measured. The fact remains that the Fourier 'bomb shell' remains unexplained.
Great video thanks... About FFT I wouold suggest you make a video abouth this... for the video script I suggest : 1) show a few composite waves... 1 pure-sin, 2 combined (1+1/2), 3 combined (1+1/2+1/4), 4 combined (1+1/4)... 2) decompose each at a time,,, from the 1st with the narrow format you shown... 2nd... etc.... 3) well... show the math for each one of them... 4) if possible show some practical examples where this methods are employed,,, ZEE
Awesome man, absolutely awesome 👍 Didn't needed to rewind even once while watching at 1.5x. + more detailed than other videos on the same topic + well explained.
Brilliant job. Didn't connect the Fourier transform aspect at all but this makes so much more sense. Will have to watch a few more times to lock this in. Thank you so much.
Why, I ask why, don't the intro physics textbooks at college level, explain it this way - in terms of Fourier transforms? It makes so much sense! thanks, Parth.
If it's not too much to ask, could YOU make a video on wave - particle duality? I'm already a pretty educated guy, but across many disciplines, so master of none, but your explanations of complex phenomena are perfectly distilled into discrete and concise concepts that you help the viewer easily visualize and understand. I'm probably going to end up watching every single video you've made lol
Actually his explanation was about Fourier series, even though the ending seems to be the Transform. The difference is in the series you work with periodic signal, meanwhile in the transform you not (you consider a infinity period). Great video though, Parth!!!
Wow, I first ran into the videos and was amazed how much I understood but especially how much I didn't. Then when I read some of the comments I got even more confused. But still, I thought the lectures totally awesome.
Bro actually Energy quantization came because bohr in his postulates told that Electron can hold specific orbit and that's how he was able to predict Single Electron system so properly. Here is some extra information for you- On trying to solve Hydrogen atom using Schrodinger equation, you will find that quantization without setting such condition.
Excellent, but i would not have understood it if I hadn't some clue of Fourier transformations of which I had little clue anyway but your video helped to understand them a little better. Still I'm struggling with them but it's not your fault. You're doing an amazing job. I love how you cleared up the idea of the light bouncing off the particle as not being the uncertainty principle, that was an awakening for me. I now know it is nothing to do with that but it is a fundamental law of physics. So much more beautiful a proof than the haphazard bouncing light.
Great content! Thanks for the simple and clear explanation!! Would also like to see how the probability distribution of the position and the momentum could be mutually fourier-transformed.
just curious if the momentum plot in your example plots was actually correlated to be the Fourier transform of the position plot in your example plots or if you just put up a general approximation. you do an awesome job by the way and so glad your viewership is growing fast! I'm putting my friends that are wanting to learn more on to your channel. way to go!
I like your videos a lot, very well explained. You might consider though, that "some" viewers are not "native listeners". Your speaking pace almost exceeds the frequency of a fax machine 😊. Relax, you'll catch the bus 😊. Best wishes from NL
Superb description, thank you. I'd love to see your explaining skills applied to gravitational waves. Specifically, how LIGO works, and what it would be like to be close to the black hole mergers that LIGO detects.
Thanks for the video. I think that if we approach this problem as the product of deltaX and deltaP being an area (integration) and we want the position X exactly (and not over some momentum interval) it would require for us to have delat P getting smaller to zero, then the wave function would gives the position but there is no momentum interval to talk about, i.e., to know the exact potion we need SUPERPOSITION of many many momentum "waves" and then we can not talk of which momentum we have, it is a superposition of many, on the other hand if we get a nice e constant momentum (nice wave with velocity inversely proportional to the wave length and constant amplitude) then we know exactly the right amount of momentum, but one wave along (this nice momentum wave) can not give us that result we need , a high amplitude single max, we need many of them and again then we do not know which one to chose out of those many waves superposed. Your comments, thanks.
Great expalination. This is first video i have seen that explain uncertinity principle in term of fourier tranform in time and frequecy domain. Otherwise it is always expalined as act of mesurement disturbs position and momentum and light particle photon interacting with measurements. As you said all tha the mumbo jumbo.
Can you discuss how the FFT and uncertainty relate to Squeezed States. In particular using Squeezed States for observation with the aim of making measurements below the natural thermal limit of a system (in terms of thermal noise, sq root 4 K T bw R). Should I be interpreting that for a system with diffuse thermal noise, define that as a spread function of say position , then FFT that to a line function for its conjugate? . Then do measurements, so that the noise spectra in the conjugated domain is now less overlapping spectra have an increased signal to noise ratio.? To be even more specific so it's easier to answer, say im measuring light and dark band positions from a double slit experiment. Do I create a conjugate dimension by mapping the light band position data with an FFT? then use the data in the conjugate FFT domain to get my increased SNR? Btw great explanations.
Why is the wave function of the momentum a fourier transform of the wave function of the position? Also, this is one of the best explanations I found online. Keep up the good work!
IMHO I don't think this can really have much of an answer (although I'm no expert, so take this with a grain of salt). It's just the math that works. I think it would be like asking, why is acceleration the time derivative of velocity? It just is the math that correctly models the physics.
well that was very enlightening in regard to common midunderstandings about heisenberg. although this does not result in the uncertainty being a property of the universe. as all this revolves around the wave function of which we know is just an assumption that currently holds up to measurement, the uncertainty principle is also only a property of an assumption.
I am a physics teacher, I can not make it that easy. Great job. Thank you
Sir you have not questioned anything of basic principles of physics that's reason you can't break it start questioning everything of physics theory you would know that physics what is being taught is bunch of lies and deceit hope you would not offended by my opinion 🙏🙏🙏
This is the most comment
@@nikis7742nobody in the world understands quantum mechanics in very simple everyday terms. The whole theory is a mathematical construct, we have no clue of its deep meaning. So I wouldn't say the teacher understands less compared to the guy in the video.
This was a better explanation than any other I've ever heard anywhere.
If you're from Science and like a little bit of math , you can check out '3blue1brown' .
Amazingly visualized
Yes, but he is talking about the uncertainty of a single quantity. And it's F-transform. But the uncertainty principle is about the product of two things position*momentum. Not position alone, and not momentum alone.
@@joeboxter3635 No, you are wrong. He literally said it in the video: the momentum is the Fourier transform of position. So the uncertainty principle is not talking about "two separate quantities," but rather, it is indeed talking about a quantity and its Fourier transform. In fact, this how conjugate variables are defined.
@@angelmendez-rivera351 u guys are so genius are u from 12 grade though
6:06 I've waited so long for somebody to actually say this.
My classmates still think that the Uncertainty Principle is a result of our "Technological Impotence".
This video is a good proof I can put forward......
Thanks a ton man.😊😊😊
Basically Einstein think same
i still do think that it because of human's lack of knowledge that we are unable to calculate both precisely
My God. You have clarified, uncertainty principle and Fourier transform in one go!!! The world needs more teachers like you. Thanks for the really simple and lucid explanation.
Great video! In uni, when I realized how "wide in real space" gives "narrow in Fourier space" and how this physically ties to the uncertainty principle - I think that was really when quantum mechanics got REALLY cool. Excellent intuitive explanation. Feynman would be proud.
Explained with simplicity.
Really good.
@@ParthGChannel I just love your work, sir. I need someone to guide, please share your e-mail id.
I’ve a compute engineering degree so I’m familiar with Fourier Transforms. And I have to say you did a beautiful job describing the simple concept behind them while leaving out the intricacies communicated by the specific mathematics
I was hopeless at maths at secondary school. So bad, in fact, that I was relegated to arithmetic class. Now, over 55 years later, I am still hopeless at maths. Fortunately, I have an interest in astronomy and science, which is steeped in maths. A lot of the subjects you bring up are fundamental to hard science and I enjoy being able to finally grasp what I am missing out on. Keep up the very good work you are doing. Physics looks like a blast once you can figure out its tools. Where was your method of explanation when I was a lad?
Einstein wasn’t very good at math either. Almost failed in elementary school math. I understand that he had his wife or someone else go over his math for completeness and accuracy.
Dude ,
Einstein was a genius, at math
Masterd diffirential calculas by the age of 15
The only reason he was not good at maths in school was because he didn't agree with a lot of things taught at the time
You must check out 3Blue1Brown's channel here on TH-cam! Trust me, his explanations are a treat!💎
More often than not I find it hard to fully comprehend subjects explained in your videos. I get the message. Most if not all the logic behind it. But due to deficiencies in my educational background and lack of any scientific experience I often fail at math or physics. Yet I find myself trying and rewinding your videos. Your explanations seem so approachable, that I always have an impression that with some extra effort (and enough replays), "I'll be there with you". Thank you for your work-is truly appreciated.
You truly have an extravagant gift for explaining things. I actually just yelled out loud WOW after 3:05. Love this channel
What I've always wondered, is WHY momentum is the Fourier Transform of position, and WHY position is the Fourier Transform of momentum. That part I don't understand, but I'll continue to look for an answer.
Well, maybe in some moment in your life, I don't known, in your school or college, you studied or will study a particular kind of waves, the harmonics waves. They have a perfect sinusoidal shape and are expressed by the following formula:
y(x,t)=Acos(kx-ωt)
Where A is the Amplitude, k is the wavenumber and ω is angular frequency.
But we can rewrite it using some identities:
k=2π/λ and ω=2πf, where λ is the waveleght and f is the frequency.
So
y(x,t)=Acos(2π(x/λ-ft)
If you notice, there is an special relation in this equation beetwen time (t) e frequency (f), they are being multiplied. Ideed, time and frequency are conjugate varibles when we are dealing with processing signs transported by electromagnetic waves. Is a consequence of the mathematic area of Fourier Analyze that when you are measuring the uncertanty of time and frequency, you need to respect an analagous inequality
ΔfΔt≥1/4π (The uncertainty principle is: ΔxΔp≥h/4π=ħ/2 where ħ=h/2π)
Fantastic, no?
So, you must be questioning about the uncertanty principle and why position and momentum are conjugate variables.
Well, I will not be able to demonstrate anything, but I can show that the pattern of t and f in the harmonic wave repeat for p and x. How?
Quantum mechanics is a kind of undulatory mechanics, and a free particle solution for Schrodinger`s equation can be at leat in it`s real part be represent by the same shape of harmonic waves:
Ψ(x,t)=Ψ_0cos(2π(x/λ-ft)
But particles in quantum mechanics follow the Broglie's relations, every particle behave like a wave and have a wavelengh, and his relation with momentum is given by:
p=h/λ, where h is the Planck's Constant = 6.62607004 × 10-34 m2 kg/s
So, if you want, rewriting the solucion of Schrodinger's Equation
Ψ(x,t)=Ψ_0cos(2π(px/h-ft)
p and x are simetrically together in the solution, like t and f. This is because they are profoundly related to each other.
I think this is not the final response for your doubt, but I think can confort some curiosity crise. Lol
See ya!
Gustavo de Oliveira
Thank you Gustavo, I truly appreciate your efforts and share your knowledge here. I really found this informative. Thank you, God bless.
He already explained in the start of the video that both position and velocity are conjugate variables
@@027_manishdixit7 Saying they are conjugate variables means nothing. It is like defining integration as the inverse of differentiation. Nobody cares what a variable is. Nobody cares what conjugate means. The question is clear and appropriate: Why are position and momentum the FT of each other? Actually it is more. appropriate to ask why certain "pairs" are so linked. And not the simplistic answer that momentum depends on wavelength and position depends on distance. Why aren''t wave number and angular frequency also paired?
It would help to know how the Heisenberg Principle was originally derived. Was it from the Schrodinger equation? If you've found out or ever find out, let me know.
I have seen heisenberg uncertainty formulas for years.
But after this explanation meaning of heisenberg uncertainty is certainty meaning in terms of what this formula is telling. 👏👏👏
No matter how long the video is , keep making such types of videos. It's really helpful to me and hopefully to other.
The explanation of the link between the Fourier transforms and the Uncertainty Principle made a lot of things clear as to how this principle is in effect. Thanks, man.
I watched Up and Atom's video on the uncertainty principle where she gave the compromising the measurement of position vs compromising the measurement of velocity explanation in terms of firing a photon with more or less energy and how much that will knock off the electron and my mind was blown by finally finding an intuitive explanation. But I immediately thought that seemed more like a limitation of the technology we have to measure than a property of the electron itself.... And right after I watched your video and my mind was de-blown and re-blown all over again just like that! haha great video!!
This is the best explanation of uncertainty principle so far! After having seeing several videos. It is understandable especially you have a STEM degree but still want to learn more about the basic physics theory.
The way he mostly keeps things real , in depth and mathematically working than that of touching topics superficially as some non-physicist ppl do
What the hell bro seriously this is the best explanation i ever herd or veiw all about Heisenberg uncertainty principle 💯.....
Brø ¡ appreciate your work🙏 you are just awesome! ☺️
Simply fantastic Partha ! Nowhere else I could find such beautiful, easy to understand, way of explaining Heisenberg uncertainty principle but also Fourier transformation. God bless you.
Found the Best way to make people love Physics... Never seen such a beautiful way of explaining "complicated" science.. ❤️
You are an outstanding explainer. Really well done.
Very succinct, worth rewinding often and reviewing. Thanks Parth
The way you explained this topic was easy to understand for a CA student. I was stucked into this topic while reading Stephen hawking book brief history of time .
Thanks parth
People always say there's no way of getting around to things that are hard, until a true genius is born. I am sure that we will have better understanding of quantum mechanics in future. Current definitions and theory are based on partial understanding.
Yeahhh finally after watching many videos i finally understood what that uncertainity principle thing actually is !!!! Thank youuu sooo much!!
I,m just glad to find someone else that's happy that the uncertainty principle is just "because maths" and doesn't like the explanation about position observations making photons bounce off particles and change the particle momentum. That alternative explanation is (as you see in the comments) just asking for people to create Heath Robinson equipment that will measure position and momentum at the same time and violate the principle.
The Heisenberg Uncertainty principle is not about our inability to measure the position and momentum in experiments, but about their actual values, which may or may not be measured in an experiment, and this is made clear using the Pilot Wave interpretation of Quantum Mechanics, which interprets the ∆ differently from the other interpretations in Quantum Mechanics. Whereas the other interpretations say ∆ corresponds to a random distribution with a range, Pilot Wave theory assumes ∆ has a Gausian distribution for the range, but with an average value in the middle.
Here is derivation of the relation: ∆f ∆wavelength >= c directly from the Heisenberg Uncertainty Principle (HUP), where f is the frequency, and c is the speed of light: ∆x ∆p >= h. But for a wave ∆x corresponds to ∆wavelength. From quantum mechanics, ∆p=h/∆wavelength = h∆f/c, since wavelength x f =c, or ∆wavelength = c/∆f. So inserting ∆x=∆wavelength and ∆p= h∆f/c into HUP yields: ∆f ∆wavelength >= c.
Using this relation, and using the interpretation from Pilot Wave theory, where the ∆ correspond to a range of values with an average. Then if light is emitted from a source, where the frequency (f) is known, then near the source the wavelength is completely unknown due to Fourier theory, thus ∆wavelength=infinity. Consequently the speed of light is infinite very near the source. But after propagating about one wavelength from the source, according to Fourier theory, ∆wavelength becomes approximately equal to the wavelength, and thus the speed of light is approximately c. At extreme astronomical distances from the source, according to Fourier theory, ∆wavelength never becomes exactly equal to the wavelength. So the speed of light never becomes exactly c.
The speed of light is not a constant as once thought, and this has also been proved by Electrodynamic theory and by Experiments done by many independent researchers. The results clearly show that light propagates instantaneously when it is created by a source, and reduces to approximately the speed of light in the farfield, about one wavelength from the source, and never becomes equal to exactly c. This corresponds the phase speed, group speed, and information speed. Any theory assuming the speed of light is a constant, such as Special Relativity and General Relativity are wrong, and it has implications to Quantum theories as well. So this fact about the speed of light affects all of Modern Physics. Often it is stated that Relativity has been verified by so many experiments, how can it be wrong. Well no experiment can prove a theory, and can only provide evidence that a theory is correct. But one experiment can absolutely disprove a theory, and the new speed of light experiments proving the speed of light is not a constant is such a proof. So what does it mean? Well a derivation of Relativity using instantaneous nearfield light yields Galilean Relativity. This can easily seen by inserting c=infinity into the Lorentz Transform, yielding the GalileanTransform, where time is the same in all inertial frames. So a moving object observed with instantaneous nearfield light will yield no Relativistic effects, whereas by changing the frequency of the light such that farfield light is used will observe Relativistic effects. But since time and space are real and independent of the frequency of light used to measure its effects, then one must conclude the effects of Relativity are just an optical illusion.
Since General Relativity is based on Special Relativity, then it has the same problem. A better theory of Gravity is Gravitoelectromagnetism which assumes gravity can be mathematically described by 4 Maxwell equations, similar to to those of electromagnetic theory. It is well known that General Relativity reduces to Gravitoelectromagnetism for weak fields, which is all that we observe. Using this theory, analysis of an oscillating mass yields a wave equation set equal to a source term. Analysis of this equation shows that the phase speed, group speed, and information speed are instantaneous in the nearfield and reduce to the speed of light in the farfield. This theory then accounts for all the observed gravitational effects including instantaneous nearfield and the speed of light farfield. The main difference is that this theory is a field theory, and not a geometrical theory like General Relativity. Because it is a field theory, Gravity can be then be quantized as the Graviton.
Lastly it should be mentioned that this research shows that the Pilot Wave interpretation of Quantum Mechanics can no longer be criticized for requiring instantaneous interaction of the pilot wave, thereby violating Relativity. It should also be noted that nearfield electromagnetic fields can be explained by quantum mechanics using the Pilot Wave interpretation of quantum mechanics and the Heisenberg uncertainty principle (HUP), where Δx and Δp are interpreted as averages, and not the uncertainty in the values as in other interpretations of quantum mechanics. So in HUP: Δx Δp = h, where Δp=mΔv, and m is an effective mass due to momentum, thus HUP becomes: Δx Δv = h/m. In the nearfield where the field is created, Δx=0, therefore Δv=infinity. In the farfield, HUP: Δx Δp = h, where p = h/λ. HUP then becomes: Δx h/λ = h, or Δx=λ. Also in the farfield HUP becomes: λmΔv=h, thus Δv=h/(mλ). Since p=h/λ, then Δv=p/m. Also since p=mc, then Δv=c. So in summary, in the nearfield Δv=infinity, and in the farfield Δv=c, where Δv is the average velocity of the photon according to Pilot Wave theory. Consequently the Pilot wave interpretation should become the preferred interpretation of Quantum Mechanics. It should also be noted that this argument can be applied to all fields, including the graviton. Hence all fields should exhibit instantaneous nearfield and speed c farfield behavior, and this can explain the non-local effects observed in quantum entangled particles.
*TH-cam presentation of above arguments: th-cam.com/video/sePdJ7vSQvQ/w-d-xo.html
*More extensive paper for the above arguments: William D. Walker and Dag Stranneby, A New Interpretation of Relativity, 2023: vixra.org/abs/2309.0145
*Electromagnetic pulse experiment paper: www.techrxiv.org/doi/full/10.36227/techrxiv.170862178.82175798/v1
Dr. William Walker - PhD in physics from ETH Zurich, 1997
This is extremely helpful compared to other videos on TH-cam, thank you for making it!
6:06 I was waiting for this. Many a people have wrong info about the uncertainty principle. However this explanation is also stated in the " Brief history of time" by hawkings.
Yes . Your channel is growing fast and I'm truly happy for that. Your channel is underrated . You deserve much much attention . I try to spread your channel as much as i can in my college ! Thanku your videos makes me happy . I'm a dropout physics student , you make me fall in love with physics again . (I'm currently doing engineering and your topics are in my syllabus)
Mate, could u come up with a video on the Fourier Transforms? U explain well, concise and clear. Guess that ll make DFT simpler explained by u.
OK, so after watching a bunch of your brilliant videos, one thing is for certain: your videos simply are not to be watched at 1.5x speed.
A rush of information so well presented and explained. Thank you Parth! :)
I watch them at 0.75 x! It is tough to keep up else. You keep thinking as he speaks and if you watch it on higher speed then the thinking interferes with the listening!
so glad that I found this channel!!!
"If a quantum particles position would be completely known, the momentum would be totally unknown". I actually think this makes sense also in the macro world. If a bullet position is completely known and fixed in space, meaning there is no time interval to measure its movement from one position to another, its momentum / velocity can not be measured / calculated. If there IS a time interval between two positions, allowing the calculation of velocity / momentum, then the position is not fixed in space.
Thanks Parth, i really enjoy listening to your podcasts.
I'm an oddity in the world of physics instructors.
I'm a Cherokee American combat veteran,who taught physics to advanced science students.
I used a significant amount of humor in my lesson plans because I read a number of articles explaining that people kept ideas they heard while laughing more deeply embedded in their memories.
Now, to address your exquisite explanation of the Heisenberg Uncertainty Principle. Actually, I don't think I could have expressed it any better than I just did.
Your presentation was simply perfect. Very well done indeed.
Now, it's my turn to instruct you in my language.
Wado means thank you and Udo means Brother.
Wado Udo! 🪶🪶🪶🪶👍🏻🤘😎
Excellent job explaining what is considered a very mathematical concept in well understood but uncompromised terms
I like your presentations a lot because you put aside math, because math can never ever explain anything, but only describing something with precision ...
But your talk do also only describe Heisenberg's uncertainty principle. You answered the WHAT it is question, but not the WHY it exist in nature question ...
You are right Uncertainty is not due to measurement, it is the inherent nature of quantum system.
Dear Parth, Could you do a video on the maths which gets applied in Physics. May be a few series. Fourier transforms, Divergence, Partial differential eqns, etc.
It would be useful.
You explanations are really great and easy to understand.
But physicists also require a little mathematics brush-up.
Thanks.
Kiran
Parth will I'm sure get round ot it. Meantime check out the math explanations given on TH-cam by 3brown1blue. They're clear, visually very well illustrated, and are very helpful.
Physicists require more mathematics than a mathematician...
really a next level explanation! thank you, bro!
Your explanations are really top notch... Heisenberg principle is a double-edged sword, but necessary given the Measurement Problem. It allows wishy-washy systems to be pinned down to a known error range, thus limiting - but not stopping - compound of errors... It also hides lots of fuzzy details and gives up on the notion of determining them. The problem is, the universe has to be deterministic deep down, or it couldn't exist. If you deny this you might as well believe in God, The Controller as well as Creator... MAGIC is not an option to proper physicists.
--
We may not be able to measure to multiple factors at once to a high enough resolution, so cannot discover deeper workings using Science (alone), it requires deduction, reasoning and leaps of faith... This is why Science is stuck in a fundamental rut.. Still, accuracy of measurement has improved on small enough scales to implement basic quantum computers. We don't really need a fully deterministic REAL unified field theory in practical reality but it would be nice to have one.
As a lecture demonstration, I used to use a storage oscilloscope, a tuning fork, and a microphone. The tuning fork Produced a nice clean wave with well defined frequency but very poorly defined duration... I then blank the oscilloscope, and clap my hands. That produced an irregular wave form totally indeterminate in frequency but very sharply defined in time.
I knew the uncertainty principle before, but now I understand the uncertainty principle. Thank you.
Great 2 for 1 offer - Heisenberg + Fourier made simple. Great video, and love your style and energy.
I agree. 2 for one. Imagine electrical engineering or system engineering with out fourier transforms and quantum physics without uncertainty principle.
With a 1964 Ph.D. in physics I was astonished that I did not know that conjugate variables were Fourier transforms of each other. Thanks.
13:05, The best moment of this video, All things started joining together, thank you soo much for this wonderful video
Very enjoyable and engaging video. In a respectable manner, I surely do envy this young guy's genius, or marginal genius. Roll on bro.
Love you dude..You content is amazing
Quantum mechanics apart...what a great teacher!
Too long?
Not even 15 minutes, and I'm just getting warmed-up!
;)
Why ??? why no body made this link before ??? You are absolutely amazing . Thank you
Very good! Thanks
I'll watch all your videos by now
wonderfully explained!! you gave every necessary bit of information and built it up really nicely, thank you :)
Even speaking is a little faster for me,I do understand your explaination very well Thanks a lot.
The bit about momentum being related to position by Fourier transformation threw me, you passed it over quite quickly as if 'everyone ' knew that. Having looked into it it certainly makes sense now. I see that some define Conjugate variables based on this dualism. I am not sure that it has always been. I think that I am supposing that there is something more fundamental than the simple fact that they are Fourier Transforms of each other.
Ya .. pls explain how they turn out to be fourier transforms of each other.
He probably didn't get into it because it involves a little linear algebra. The position and moment are not just a number as he mentioned, they are a operators. If two operators commute then x * y = y * x. If they do not commute then x * y does not = y * x. In our case "momentum space" and "position space" do not commute so if you perform a Fourier Transform to go from position space to momentum space you end up with this hbar/2 term he discusses. This is how I think of the uncertainty principle. It's true of any non commuting operator, but you don't have the hbar term because it's not quantum mechanics.
@@zacharywarner1806 Sorry but that is a load of bollux. Somewhere in that mish mash might be a kernel of truth but the way you have described it makes not one iota of sense. It is also stuff all to do with linear algebra although I do understand that Quantum Theory can be described thus under The Copenhagen Agreement where by Hermitian operators define what can actually be measured. The fact remains that the Fourier 'bomb shell' remains unexplained.
I do have to add my thanks though to you Zachary, you made a good fist of explaining it to me and I went off on one. My apologies for that :-)
Conclusion: it's not the default in our instruments that we have but it's the fundamental concept that how the universe work
The measurement problem is currently unsolved, so it could go either way.
Great video thanks...
About FFT I wouold suggest you make a video abouth this...
for the video script I suggest :
1) show a few composite waves... 1 pure-sin, 2 combined (1+1/2), 3 combined (1+1/2+1/4), 4 combined (1+1/4)...
2) decompose each at a time,,, from the 1st with the narrow format you shown... 2nd... etc....
3) well... show the math for each one of them...
4) if possible show some practical examples where this methods are employed,,,
ZEE
The conceptual is trickier in some ways than the mathematical. Thanks for this video series that tackles concepts. You are the best, Parth!
Great teaching……and amusing as well. Keep it coming
Awesome man, absolutely awesome 👍
Didn't needed to rewind even once while watching at 1.5x. + more detailed than other videos on the same topic + well explained.
Thank you this helps clean up my very rudimentary understanding of Heisenberg's Uncertainty Principle.
Brilliant job. Didn't connect the Fourier transform aspect at all but this makes so much more sense. Will have to watch a few more times to lock this in. Thank you so much.
Why, I ask why, don't the intro physics textbooks at college level, explain it this way - in terms of Fourier transforms? It makes so much sense! thanks, Parth.
I have never seen explanation like this.awesome
If it's not too much to ask, could YOU make a video on wave - particle duality? I'm already a pretty educated guy, but across many disciplines, so master of none, but your explanations of complex phenomena are perfectly distilled into discrete and concise concepts that you help the viewer easily visualize and understand. I'm probably going to end up watching every single video you've made lol
(I'm not crazy I promise, I realized that sounded a lil stalkerish lmao) >_> Just fascinated on the physics content!
thank you so much! you went quite in depth! A LOT of info., i will try to review it a few more times !
Actually his explanation was about Fourier series, even though the ending seems to be the Transform. The difference is in the series you work with periodic signal, meanwhile in the transform you not (you consider a infinity period).
Great video though, Parth!!!
LOVE FROM KASHMIR ( INDIA )❣️
Finally some good and new explainatiin
Atlast I found how to watch your videos.... Click the three dots reduce the playback speed to 0.75x ...thank god
Thank you, 10 more viewings will help. Excellent synopsis. Takes the spooky stuff out, logic in.
6:14 i was waiting for this line
Wow, I first ran into the videos and was amazed how much I understood but especially how much I didn't. Then when I read some of the comments I got even more confused. But still, I thought the lectures totally awesome.
I'm requesting for a topic .
" Bohr theroy and Energy levels of atom "
Why the enegry has to be discrete for a energy shell??
Bro actually Energy quantization came because bohr in his postulates told that Electron can hold specific orbit and that's how he was able to predict Single Electron system so properly. Here is some extra information for you- On trying to solve Hydrogen atom using Schrodinger equation, you will find that quantization without setting such condition.
Excellent, but i would not have understood it if I hadn't some clue of Fourier transformations of which I had little clue anyway but your video helped to understand them a little better. Still I'm struggling with them but it's not your fault. You're doing an amazing job. I love how you cleared up the idea of the light bouncing off the particle as not being the uncertainty principle, that was an awakening for me. I now know it is nothing to do with that but it is a fundamental law of physics. So much more beautiful a proof than the haphazard bouncing light.
Really enjoy this series! Keep 'em coming :)
Great content! Thanks for the simple and clear explanation!! Would also like to see how the probability distribution of the position and the momentum could be mutually fourier-transformed.
Great video. You made such a difficult concept so interesting and simple 😊.
Really well explained!!!
Love the way you explain Fourier.
Wish you make a video just about Fourier Transformation but with some more details.
Wow that's a very cool explanation about uncertainty principle never heard before like this one
Always such a pleasure to listen to your explanations! 👏👏
just curious if the momentum plot in your example plots was actually correlated to be the Fourier transform of the position plot in your example plots or if you just put up a general approximation. you do an awesome job by the way and so glad your viewership is growing fast! I'm putting my friends that are wanting to learn more on to your channel. way to go!
I like your videos a lot, very well explained.
You might consider though, that "some" viewers are not "native listeners".
Your speaking pace almost exceeds the frequency of a fax machine 😊.
Relax, you'll catch the bus 😊.
Best wishes from NL
Thank you for explaining it in some way other than experimental error
Just amazing! Today I got the feel of this concept.
A phenomenal explanation.
Superb description, thank you.
I'd love to see your explaining skills applied to gravitational waves. Specifically, how LIGO works, and what it would be like to be close to the black hole mergers that LIGO detects.
Thank you so much Parth!!!
Thanks for the video. I think that if we approach this problem as the product of deltaX and deltaP being an area (integration) and we want the position X exactly (and not over some momentum interval) it would require for us to have delat P getting smaller to zero, then the wave function would gives the position but there is no momentum interval to talk about, i.e., to know the exact potion we need SUPERPOSITION of many many momentum "waves" and then we can not talk of which momentum we have, it is a superposition of many, on the other hand if we get a nice e constant momentum (nice wave with velocity inversely proportional to the wave length and constant amplitude) then we know exactly the right amount of momentum, but one wave along (this nice momentum wave) can not give us that result we need , a high amplitude single max, we need many of them and again then we do not know which one to chose out of those many waves superposed. Your comments, thanks.
Great expalination. This is first video i have seen that explain uncertinity principle in term of fourier tranform in time and frequecy domain.
Otherwise it is always expalined as act of mesurement disturbs position and momentum and light particle photon interacting with measurements. As you said all tha the mumbo jumbo.
best explanation...👌👌👌
Easy digestible information at one place!
This was a great explanation
thanks man
Can you discuss how the FFT and uncertainty relate to Squeezed States. In particular using Squeezed States for observation with the aim of making measurements below the natural thermal limit of a system (in terms of thermal noise, sq root 4 K T bw R).
Should I be interpreting that for a system with diffuse thermal noise, define that as a spread function of say position , then FFT that to a line function for its conjugate? . Then do measurements, so that the noise spectra in the conjugated domain is now less overlapping spectra have an increased signal to noise ratio.?
To be even more specific so it's easier to answer, say im measuring light and dark band positions from a double slit experiment. Do I create a conjugate dimension by mapping the light band position data with an FFT? then use the data in the conjugate FFT domain to get my increased SNR?
Btw great explanations.
Adding "0:00 - Intro" to the description would enable use of the chapter feature. I know it's an old video, but it would be nice.
Why is the wave function of the momentum a fourier transform of the wave function of the position?
Also, this is one of the best explanations I found online. Keep up the good work!
I'm glad I stumbled upon this channel in my junior high school! Subbed!
IMHO I don't think this can really have much of an answer (although I'm no expert, so take this with a grain of salt). It's just the math that works. I think it would be like asking, why is acceleration the time derivative of velocity? It just is the math that correctly models the physics.
@@EliteTeamKiller2.0 Thanks, this makes me fell less pathetic
well that was very enlightening in regard to common midunderstandings about heisenberg. although this does not result in the uncertainty being a property of the universe. as all this revolves around the wave function of which we know is just an assumption that currently holds up to measurement, the uncertainty principle is also only a property of an assumption.
Are you a physics teacher or a student? your explanation is really clear!