What is the Heisenberg Uncertainty Principle? A wave packet approach

Рет қаралды 271,009

Жыл бұрын

In this video I would like to answer a simple question: according to quantum mechanics, how do you describe a freely moving particle? It sounds simple, but what we will discover is that by attempting to answer this question, we will actually uncover one of the most profound ideas in physics, Heisenberg’s Uncertainty Principle, which tells us that it is impossible to simultaneously know where a particle is located, and how fast it is moving, implying that there is a fundamental limit to our knowledge of the physical universe. It is a principle that lies at the heart of quantum mechanics, and it has revolutionised our understanding of the fundamental laws of physics. So, buckle up, and get ready for the ride.
References for this video:
Quantum physics of atoms, molecules, solids, nuclei and particles - Eisberg and Resnick
A student's guide to the Schrodinger equation - Daniel A. Fleisch
Introduction to Quantum Mechanics - Griffiths and Schroeter
Introduction to Quantum Mechanics - Phillips
Vibrations and Waves - King
Gabor Representations - Caltech (www.its.caltech.edu/~matilde/...)
Wave Packets and Dispersion - Matthew Schwartz (scholar.harvard.edu/files/sch...)
The Quantum Story - Jim Baggot
Quantum Physics for Dummies - Steven Holzner
Thirty Years that Shook Physics - Gamow
Inward Bound - Abraham Pais
You can help support this channel via the Physics Explained Patreon account: / physicsexplained
You can follow me on instagram: / physics_explained_ig
You can follow me on Twitter: / physicsexplain1
iopscience.iop.org/article/10...
iopscience.iop.org/article/10...

Пікірлер: 635

@PaulisInclusion Жыл бұрын

Easily one of the best physics channels. Thank you for not dumbing things down and showing the math.

@Patrick_Rangel Жыл бұрын

Effectively, any attempt reduce the Physics the verbal expression, ignoring the Math, is condemned the futility chronic; *Physics without Math is stupidity!*

@kenzzz3998 Жыл бұрын

This! ^ I hate when people try to make things too simple cuz I always feel like I'm missing a lot

@richardleetbluesharmonicac7192 Жыл бұрын

The best scientists can explain complex concepts, anecdotally, and not have to show the math, which is not really relevant to the concept. Your air of superiority is kind of disturbing because it’s subjective.

@fish1389 Жыл бұрын

@@richardleetbluesharmonicac7192 not really

@andrewhancock2451 Жыл бұрын

Not only did he retain the details, but he presented them in very digestible form. You still need the tools (Fourier Transform, windowing, envelope modulation of a carrier, group and phase velocities, etc.), but if you have seen the concepts before, you have the high level view of how the come together.

@spythere Жыл бұрын

Wait, this video was already posted. But since nobody observed it it was at its superposition and now it was observed once more and become real.

@xbzq Жыл бұрын

I observed it but no one observed me so I'm like a cat in a box.

@kallekula84 Жыл бұрын

He took it down while I was 15 minutes in to the video was super frustrating been waiting for the reupload since!!

@p.b.2903 Жыл бұрын

I think he realized there were errors in his Euler equations. I think he just couldn’t help but take it down and fix it:

@mihailmilev9909 Жыл бұрын

@@xbzq lol

@peterfireflylund Жыл бұрын

@@xbzq Not a friend of Gene's, are you?

@idrisstahiri186 2 ай бұрын

Does anyone know what happened to the creator? This is one of my favorite channels and it’s sad to see it inactive for a year

@casualbeluga2724 Ай бұрын

I was wondering the same thing myself

@sachinsrb Жыл бұрын

This is simply the best channel for real physics concepts rather than over simplifying things for a much broader audience for just awareness. Awesome work. Congratulations for a fantastic mathematical explanation. Using real mathematics is the key here. Thank you.

@PhysicsExplainedVideos Жыл бұрын

Wow, thanks! Glad you enjoyed it :-)

@JayaLakshmi-dm3ys 9 күн бұрын

@@PhysicsExplainedVideos brother can u make a complete series for general relativity.please

@alexandreolle2340 Жыл бұрын

Your ability to naturally bring your audience to understand fundamental laws of physics is unmatched as far as I'm concerned. Brilliant work again, thank you !

@PhysicsExplainedVideos Жыл бұрын

Thanks for the kind words, much appreciated!

@AltamashDeshmukh-im2od 2 ай бұрын

No drama no time waste Pure knowledge a channel dedicated to the lovers of physics

@NumbToons Жыл бұрын

I was confused about how do we get localised wave packet by adding more and more waves. But HOOOOOLY, your video explained exactly that, and EXACTLY the same way I always try to understand things (by trying small experiments with equations, before understanding the final general result). Clearly the Best Physics channel.

@-leelakrishnan1970 11 ай бұрын

This is easyly the best channel that delivers lectures on physics.Your spot on explanations with respect to the choice of the applications of mathematics is really exemplary.Easyly the best teacher.Indelible comments.

@4m0d 7 ай бұрын

i was reminded of the phenomenon of beats in sound waves, where superposition of two similar frequencies creates a pulsing amplitude

@federicovalentin2980 Жыл бұрын

This has been my favourite channel for a while, I love pbs spacetime, veritasium, science click and watching lectures , but this is above

@PhysicsExplainedVideos Жыл бұрын

very kind of you to say

@chandrasekarang948 Жыл бұрын

Never stop posting videos, you're the only channel that goes through mathematical details in depths. Thank you so much.

@schmetterling4477 Жыл бұрын

Why do you want him to keep posting more bullshit like this? :-)

@tjd_1274 Жыл бұрын

This is by far my favourite physics channel, it blends a mini-lecture series with a nice historical storyline. After doing a PhD the only chance you get to do lecture formats are at summer schools and you forget most of the undergrad physics which is way nicer to talk about with your friends. I look forward to your next video :)

@mosesgunn6937 Жыл бұрын

Your explanatory abilities are second to none. What a tour de force this is.

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it! Thanks for taking the time to leave a comment

@NumbToons Жыл бұрын

I was actually learning about Uncertainty Principle and everywhere I was finding same 5 lines over and over, I kept searching more and more. I kept video on hold for the end, so that when I have gained the general background for the topic, I will watch your video to finish it all. AND OH BOY! Did my plan work. This video cleared all my doubts and confusions about the uncertainty principle.

@school6268 Жыл бұрын

Best physics channel on the platform by orders of magnitude

@PhysicsExplainedVideos Жыл бұрын

Kind of you to say!

@jamesbentonticer4706 Жыл бұрын

It's a shame you have to lose all those views that the original upload received. The clarity of your videos is fantastic and I appreciate the mathematical rigor you inclue.

@cademosley4886 Жыл бұрын

I have a feeling those views came right back here as soon as they could. A person can't just watch it once. XD

@jamesbentonticer4706 Жыл бұрын

@@cademosley4886 good point

@Just.A.T-Rex Жыл бұрын

It’s all good I sleep almost each night.😊

@ToriKo_ Жыл бұрын

Why was the original removed?

@escapeenrique Жыл бұрын

❤i font earlier

@drbeanut Жыл бұрын

This is awesome... I was recently playing around with the concept of HUP and was trying to figure it out myself. I took a different route. I just played with Desmos Graphs and manipulated sine/cosine wavefunctions until I got something... I arrived at the same result, and then worked backwords to find I was just adding together pure waves continuously. So much become so obvious in that moment. The single-slit, or what I really now think of as double-barrier, experiment REMOVES/DEAMPLIFIES component wavefunctions from the superposition, hence closing in on the pure wave, revealing diffraction gradients, instead of a "no-slit/no-barrier" laser dot.

@peterhughes3648 Жыл бұрын

This is probably the best physics channel on the internet; clear, rigorous, and superbly well explained. Thank you.

@MagalaxeurDETER Жыл бұрын

Bro are you a top physics teacher!? I haven't seen such clarity on how to explain the uncertainty pronciple in a short 1hr video. I had a full semester of quantum mechanics at university and not a teacher was able to explain the fundamental reason in 6 month time! Keep on making more videos please!

@PhysicsExplainedVideos Жыл бұрын

Glad that it has helped!

@Shadowless_Kick 5 ай бұрын

With his in depth physics understanding and great math skills, he is qualified to be a top school professor than a “teacher”.

@momchi98 Жыл бұрын

Why in God's name was quantum never explained to me like this by my university. We did alot of exercises, but the principles like Schrodinger's equation and the uncertainty principle were treated like axioms. And it didn't take super advanced mathematics either. Thank you so much for this video. My passion for physics burns abit brighter every time I watch a new upload of yours.

@PhysicsExplainedVideos Жыл бұрын

Glad to hear it! Thanks for taking the time to leave such a positive and encouraging comment

@petereldergill2942 Жыл бұрын

Been waiting months and am so glad you were able to re-post it. Hopefully be able to watch it soon. I need to make up and edit some physics exams first though. I love all your videos and thanks for such high quality work, mixing theory, history and general interest! Cheers from Toronto

@PhysicsExplainedVideos Жыл бұрын

Thanks for the comment and kind words, I really appreciate it

@brucechappell1539 Жыл бұрын

So happy to see a new video posted! These help me stay conceptually in touch with my university education that I don't get to use so much at work. Love sitting back and watching you explain the theory and the math!

@dartplayer170 Жыл бұрын

Definitely the best explanation of the Uncertainty Principle that I've ever seen

@PhysicsExplainedVideos Жыл бұрын

Glad it was helpful :-)

@bathhatingcat8626 Жыл бұрын

What’s interesting is that it’s basic quantum- like 2nd year college stuff. He just explains it very clearly. Physics teachers can learn a lot from this channel

@mangolassi_. 5 ай бұрын

Wow, this is really awesome. Makes me understand - or at least somewhat comprehend - wave functions in quantum physics nearly 20 years after I miserably failed at this in school.

@steveboigon5478 10 ай бұрын

Congratulations!! More than 10 million people have watched your terrific videos. You have an engaging teaching style and you do not scrimp on the Math! Its always a joy when you post a new one!!

@thadaeusb6667 Жыл бұрын

Another superb, detailed deep dive into physics. Top.

@PhysicsExplainedVideos Жыл бұрын

Glad you liked it!

@chriszachtian Жыл бұрын

Allready missed the Vid. Thanks for sharing knowledge with a certain background! Most other channels do not dare that. Hopefully, your success enforces you to continue.

@PhysicsExplainedVideos Жыл бұрын

Thanks for the kind words and encouragement, I really appreciate it!

@kristofferbouchard8395 Жыл бұрын

I can only imagine a probability distribution of the amount of effort you put into making this video. Thank you for your efforts, you have increased my understanding of QM, limited as our definition of understanding may be.

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@shazmunchdylbertoid Жыл бұрын

I am so happy this is back up. thank you for your excellent work!

@renedekker9806 Жыл бұрын

Absolutely love your videos. They are the physics videos that are the most clearly explained, while still going into all the details an math. It would be fantastically great if you could do a follow-up on this video, describing how things change for fast moving particles, taking Special Relativity into account.

@cruser1381 Жыл бұрын

I admire your passion for physics. It’s so sad how these stories aren’t well told or known in popular culture. The transition from classical physics to QM is such a great story in human history and needs to be told better.

@PhysicsExplainedVideos Жыл бұрын

I completely agree, an incredible story

@Arthurnate Жыл бұрын

Carlo Rovelli's Helgoland is a brilliant book on the discovery 🙏

@peterfireflylund Жыл бұрын

@@Arthurnate Three cheers for hay fever!

@lidamullendore6166 10 ай бұрын

Truly excellent, both in content and the pace of presentation. Love the visuals as they give an immediate intuitive feel for the equations. I totally agree that this is one of the best physics channels!

@aditya.21 Жыл бұрын

Always love your work!! Never stop bringing to us more fascinating stories and concepts with fundamental Mathematical Approach!!

@multicoloredwiz Жыл бұрын

Every time I watch a video you created, it's so succinct (I realize they're around one hour lol) and beautiful and satisfying.. thank you. I don't know how much time you spend on them, but you're a damn fine educator

@PhysicsExplainedVideos Жыл бұрын

Thanks for the kind words, I really appreciate it! Glad you enjoy the videos

@abrarjahin8848 6 ай бұрын

this channel is literally the best.. it helped me everytime i studied quantum physics

@MrAe1966 6 ай бұрын

Brilliant video. I have understood more in 1hr than in my whole chemistry degree course more than 30 yrs ago.

@user-sc2cz4hp3z 2 ай бұрын

Why unfornutely are you not making more videos?

@stauffap 2 ай бұрын

I've never seen this explained with such clarity. You resolved a question i had for a very long time and it was very easy to follow. I can't thank you enough!

@cademosley4886 Жыл бұрын

Huzzah! I really like this one because I feel like a free particle is the first most basic thing one should understand, and this explains it like a champ. The infinite square well is easier to get, but it feels more like a side road on the way to the real motorway. This is what I was waiting for.

@PhysicsExplainedVideos Жыл бұрын

I completely agree, the free particle is a gem

@highkey4316 3 ай бұрын

holy mother of god this was the perfect video. not all of the math was crystal clear to me as a first-year in college but the process you took in superposition made amazing sense. I can already see myself revisiting this video in future years as I continue in my quantum physics studies. thank you a million times over for creating this.

@hgtrad7655 Жыл бұрын

Top explanation, probably the best going through the maths. you even prepare the grounds for a knowledgeable reader to grasp the incredible implications beyond the narrative. Thank you.

@rubenvalenzuela8837 Жыл бұрын

He's back! Very grateful for this content; high quality and accessible to everyone.

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@prochafilho Жыл бұрын

I am waiting anxiously for your new videos. Your ability to distill complex physics theories and math is so satisfying. By far, one of the best physics KZfaq channels.

@PhysicsExplainedVideos Жыл бұрын

Thank you, very kind of you to say!

@kennybeach342 9 ай бұрын

This channel, and this Playlist specifically is helping me pass modern physics!!! Thank you for making this!

@sphakamisozondi Жыл бұрын

Bro, I thought you would never come back! Amazing content as usual!

@steveboigon5478 5 ай бұрын

Several have commented that since you have not posted in more than a year, and have not responded to questions about your videos, that we can only assume that you are no longer active here and have moved on.. I will no longer check in here looking for more content. I really enjoyed the videos you did post, and I wish you well. If I am incorrect, and you will continue posting, then please let your followers know

@wyrmhero4275 Жыл бұрын

superb video, best physics channel on youtube. Period. Keep up the great work!

@PhysicsExplainedVideos Жыл бұрын

Thanks!

@MarkoTManninen 20 күн бұрын

My long-standing questions about pinpointing the difference of classical and quantum wave theory in the level of mathematical formalism is finally answered. Imaginary units are needed for separating wave packets. Real trigonometric functions can have phase but varying amplitudes simply turns out with complex numbers. Even thought, what would prevent on using sine'cosine in place of them? Instead of six independent components on classical phase space there is a beautiful ratio between position and momentum in quantum wave function. Well done!

@ezequielwolcan7632 Жыл бұрын

Excellent video! I watched it twice and when I went for the third I saw it had disappeared. I am very grateful it's back!

@jesse4202 Жыл бұрын

After months of struggling to understand this concept, coming back a year later with this video and being able to understand what seemed like such a complex topic is eye opening. Thank you again Mr. Explained for your work. Continue strong !

@PhysicsExplainedVideos Жыл бұрын

Great to hear!

@iceman200200 3 ай бұрын

Wow, really excellent explanation. I've understood this information for a while (was a physics major), but never saw it explained so well

@r.i.p.volodya 10 ай бұрын

Great as always !

@moleman1976 2 ай бұрын

This is a phenomenal video! I wish it had been around when I was studying physics in the late 90's! You do a great job of simplifying the arguments, while still staying strong on scientific roots!

@albertwesker9119 Жыл бұрын

I've waited a lot for your video and it's finally here

@PhysicsExplainedVideos Жыл бұрын

Enjoy!

@Rudrakxh Жыл бұрын

This is exact moment when Werner became Heisenberg.

@CarlosPilaf70 Жыл бұрын

fantastic explanation, I could follow and it was beautiful.

@drbeanut Жыл бұрын

Last part of the video was beautiful mathematics, well done sir.

@drbeanut Жыл бұрын

Really connecting all the dots here. I think a great follow-up video to this would be how we go from the uncertainty principle in theory to how it reveals itself in experiment. Moreover, how particle-confinement changes the the time-dependent broadening, or how it is possible to produce the opposite result.

@dutonic Жыл бұрын

a phenomenal supplement for reviewing for second semester quantum. Your channel is a godsend

@PhysicsExplainedVideos Жыл бұрын

Glad it was helpful!

@andrewferris8169 Жыл бұрын

A video in this style on gauge theory and forces would be incredible.

@PhysicsExplainedVideos Жыл бұрын

definitely on my to do list. Currently working on a video on the Dirac Equation. Working towards gauge theory

@terryyu625 Жыл бұрын

love this channel to show us beautiful structure of math under the physical concept!

@KipIngram Жыл бұрын

This is a very good piece of work. Well done!

@WelshyPilotGuy Жыл бұрын

That was mesmerising , thank you so much for taking the time to prepare such a beautiful presentation. 🙏

@ianmichael5768 Жыл бұрын

Although there will always be some uncertainty in my perception and understanding of reality (h), I truly thank you for creating this content and clarifying concepts. I used to hate superposition at university. Now, I walk in nature and enjoy the simplicity of it. Cheers

@anderoo9260 6 ай бұрын

Understanding this video and being able to calculate these things is my goal. I failed calculus in college a few years ago, so I'm starting at derivatives. I was always mediocre at best at math's and went downhill since high school. I absolutely detested math's But physics is so fascinating that I picked math up and been studying for a few months now. If I will be able to do this stuff, integers and all- I'll be a happy man

@TheAngelOfDeath000 5 ай бұрын

Great video! I’m already in my first year of college pursuing my Ph.D in Astrophysics / theoretical physics, I specialize more in the study of black holes!

@TheAngelOfDeath000 5 ай бұрын

In other news, where have you been man, it’s been 1 years? Are you ok?

@LydellAaron Жыл бұрын

Fantastic job explaining this material

@Jeducation22 Жыл бұрын

finally! I was about two-thirds of the way through the video before you took it down. The last week was like waiting for the next episode of 24!

@PhysicsExplainedVideos Жыл бұрын

Hope you enjoyed it!

@nemurerumaboroshi Жыл бұрын

Fantastic stuff. Few pieces clicked into their proper place. Thank you!

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@Beltandjacketowner 2 күн бұрын

I am really hopping for more videos. These are fantastic! ❤

@nahichak1003 8 ай бұрын

FANTASTIC VIDEO. GREAT JOB. THANKS !

@eamonnsiocain6454 Жыл бұрын

Excellent! Thank you!

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@theonlinezone6904 Жыл бұрын

thanks for explaining where formulas comes from, it makes a lot easier to understand this complex topics

@mdonnang Жыл бұрын

For me the epiphany of this video starts at 50’55”: A brilliant visualization demonstrating the uncertainty of position and momentum relationship! I finally understood Heisenberg’s principle. Superb video, thank you!

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@cosmicnomad8575 10 ай бұрын

Absolutely legendary channel

@NEWDAWNrealizingself Жыл бұрын

THANKS ! MATHEMATICALLY AND ELEGANTLY EXPLAINED THE UNCERTAINTY RELATIONSHIP, WELL !

@ThomasHaberkorn Жыл бұрын

I love this video. Such a satisfaction to connect the dots in my patchwork of knowledge about this stuff.

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@stewarthayne8304 Жыл бұрын

Thanks for producing these with the math!

@lucyfrye6723 Жыл бұрын

Is this how it historically went down? We are looking for a wave that is localized, now lets find an equation that does this for us and the probability distribution just rolled out of it naturally because it was needed.

@PhysicsExplainedVideos Жыл бұрын

As far as I know, this is not the historical route to the uncertainty principle. Perhaps I will look at this in a future video

@mctrafik Жыл бұрын

Took me 3 sessions, but sat through the whole thing. Nice. Love this content.

@PhysicsExplainedVideos Жыл бұрын

Glad you enjoyed it!

@nithinhm13 Жыл бұрын

Excellent work... as usual !!! Coincidentally, I was teaching the exact same concept in the exact same way to my engineering students a few days back. This will be a great resource for them. Thank you for this.

@PhysicsExplainedVideos Жыл бұрын

Great 👍

@julians7785 Жыл бұрын

Amazing video. Thank you!

@vermasean Жыл бұрын

So glad I stopped by the channel; my alerts were set, but didn’t get the notification. Love the work! 🙌

@PhysicsExplainedVideos Жыл бұрын

Thanks!

@julius-theodorbarth3893 Жыл бұрын

Man your videos are a blessed miracle, just fantastic

@PhysicsExplainedVideos Жыл бұрын

Thanks!!

@mk-wo6jg Жыл бұрын

This is the first video that made me want to sponsor a KZfaq video. I just finished my undergraduate degree in astronomy and now I'm doing my master's degree in numerical simulation. Quantum mechanics is not essential to my research process, but I have always wanted to understand the principle of uncertainty. I also read shankar's book to myself, but I was frustrated because I didn't fully understand it. But this video gave me intuitive and perfect solution and confidence to read shankar's book again. Thank you very much. This short one hour video outperforms EVERY videos and EVERY QM lectures that I take in my undergraduate coures. Really really thankful to you.

@schmetterling4477 Жыл бұрын

Either your country's educational system sucks lemons or you are lying about your education. Possibly both. ;-)

@mk-wo6jg Жыл бұрын

Sadly, you're right.

@schmetterling4477 Жыл бұрын

@@mk-wo6jg That was not much of a riddle.

@mk-wo6jg Жыл бұрын

Hahaha yes :( I think you are good at physics. Ur major also physics?

@schmetterling4477 Жыл бұрын

@@mk-wo6jg PhD.

@Sciencedoneright 4 ай бұрын

Man, I miss your videos, please upload more!

@makespace8483 Жыл бұрын

Just superb!

@PhysicsExplainedVideos Жыл бұрын

Many thanks!

@samuelnyaachi7094 Жыл бұрын

Excellent work.

@VikramchauhanChauhan-pn5ol Жыл бұрын

excellent video.. keep doing good work.

@Hkj2000 Жыл бұрын

As it so happens, I was studying the same topic on my own and this video really helped me clear the fussiness in the concept I had in my mind. Thank you so much for creating this amazing video. I spent a lot of time and effort trying to understand this topic better.

@PhysicsExplainedVideos Жыл бұрын

Glad it helped!

@ronaldjorgensen6839 Жыл бұрын

thank you for your prescience great stuff staff and viewer

@watermelon9209 Жыл бұрын

super informative! Expecting your next video!! many thanks!

@PhysicsExplainedVideos Жыл бұрын

Glad you liked it!

@kevincleary627 Жыл бұрын

You are so great at explaing things at more than just a superficial level I would love to see you do a lecture on the Higgs mechanism in your usual level of rigor. Thanks for all your videos!