The real intuition behind Heisenberg's Uncertainty Principle!

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I love how every time you make a video like this you talk as if you brought the scientists back from the dead and had lunch with them to make this video.

Now I understand. It's been 30 years of me trying to understand the uncertainty principle. I started as a 14-year-old and a high interest in physics, but no one was ever able to just break it down and explain it to me like this. Thank you, side quest complete.

The sign of a great genius is to be able to explain a complex subject to an idiot, like me, in a way I can understand! Thank you so much!

Honestly, as an Indian, I never expected some Indian to be this passionate about Physics, a person really wants to understand physics for the sake of Physics, at least until now. It was my friend who first suggested your video about Quantum Spin. I thought it would be just like any other video about physics, a Lecture with a bunch of mathematical relations and claim something to be true just because math does imply so. I know and I agree that Quantum and Relativity are not intuitive in our common sense and it's true because what we say common sense, is just a genre of experiences in the macroscopic world, a classical world. Still, there is always room for improvement we can extend our domain of intuition by asking the right questions and that's what you do best. Really, I always wanted someone to share the same passion for Physics. I have seen all your videos and all I want to say is "Keep on doing"

Mahesh… that was exceptional! Thank you… my uncertainty on this is now far more certain while making my certainty more uncertain!!

Whenever I tell my students about quantum theory, I always try to highlight how necessary it is. The wave-particle duality is the entire reason we have atoms. If the electron is not a wave, but a particle, then all atomic orbitals decay in about 16 picoseconds. You can use the uncertainty principle alone to back-of-the-envelope estimate the order of magnitude an electron's energy at various distances to a proton. Within nuclear scales, it'd be enough to shoot it clean out of the proton's attractive potential. At the scale of the Bohr radius, it's on the order of a dozen or so electron volts, in agreement with the Schrödinger equation. The uncertainty principle actually implies a repulsive force between the proton and electron at sufficiently short distances, preventing orbital decay. Even though I teach this, it never fails to blow my mind every time I think about it.

Bro explained the Heisenberg Uncertainty Principle in the first 1 minute of the video better than I've EVER heard anyone explain it. Makes PERFECT INTUITIVE SENSE now. Thanks so much!! Edit: I watched the rest and yes that's the less accurate version but it ended up still working for me because I didn't assume you could determine velocity by just going to the next slide because I assumed there was no next slide, which ended up working for me. However, the next explanation he gave was even better anyways so ... win win!!

This is genuinely the best science education channel out there man. Have never left any of your videos without having learned something new or in a better way than I previously understood it.

Time and frequency are also complementary variables. A sinewave extends to -inf to +inf. This gives us a pair of impulse functions (infinitesimally wide, but infinitely tall pulses) in the frequency domain when we take the Fourier transform. When we look at a sinewave for a non-infinite amount of time, we are always chopping off some of the sinewave (Rectangular window function). This causes the frequency spectrum to of the impulses to spread out (convolving with the fourier transform of the window function in the frequency domain). This spreading of the sinewave's spectrum gives us an uncertainty on the actual frequency of the non-chopped sinewave. If you look at the sinewave for a shorter period of time, the spectral spreading of the sinewave, and your uncertainty about the frequency of the sinewave gets worse.

Finally, Mahesh is heading towards the intuition of Quantum Physics!!!!!!

A similar thing can be observed for signals in time and frequency domains. Signals which are non-zero for low time duration have their spectrum spread apart in frequency and vice versa. For instance, Fourier transform of an impulse (infinitesimally small duration signal) is constant ( i.e. spread over entire frequency spectrum) whereas Fourier transform of a sinusoidal signal (spread in time domain) consists of impulses in the frequency domain.

"...hold my cat!" Cracked me up! 😅🤣😂🙃😊

Mahesh, again, good job on a complex topic. As a physics grad from the 80s, the thing I need better intuition is how Schrodinger arrived at his equation after saying "Hold my cat".

Listening to Mahesh pronounce “probability” is priceless. We love you Mahesh. ❤

A fun way to get a feel for the phenomenon is to play with a sound editor like Audacity, mix in some beeps of varying lengths and pitches (arranged into chords, even), then show the track in Spectral view mode. You can adjust the vertical (frequency) resolution as much as you like, but doing so smears out the horizontal (time) resolution and vice versa. A note can only have a pure frequency when it is eternal, and a very short note is just a click, composed of all many frequencies.

"Wow, this video is truly inspiring! It's just incredible how 'INTUITIVE ' this lesson was .This is a really underrated channel, u deserve more bro. Big props to Mahesh for simplifying such a genuinely important and" hard to get ur head around " topic!"

I really love this guy's teaching style, his knowledge, and his excitement for physics. Mahesh is unique.

This is the first time I've come close to understanding this topic Great work.

Almost 20 years ago, I first came across the uncertainty principle in Class XI Chemistry studying the atomic structure. This is the best explanation yet. Indeed intuitive. And over the years, I've realised that it's not that some subjects and some topics are tough, it is the quality of books and quality of the teachers that make a difference!! And if you're not in luck with the teacher's quality, do get good quality books!!