Lagrangian Mechanics: How powerful is it?

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  • Опубликовано: 26 ноя 2024

Комментарии • 1,2 тыс.

  • @ScienceAsylum
    @ScienceAsylum  5 лет назад +195

    If you're looking for more on Lagrangian mechanics, there's a whole chapter in my eBook on it (Chapter 4): gumroad.com/l/ubSc I even use the double pendulum as one of my examples, if you were itching for more detail. 🤓

    • @adamroach4538
      @adamroach4538 5 лет назад +16

      You have an ebook😱

    • @gumunduringigumundsson9344
      @gumunduringigumundsson9344 5 лет назад +9

      An eBook..?!?
      Holy mole! 🌟🌟🌟🌟🌟

    • @baptistebauer99
      @baptistebauer99 5 лет назад +9

      I bought the book! :)
      I had encountered the Lagrangian before, but it was the Euler-Lagrange equation applied to describe some quantum energy weirdness that I didn't understand at all. I didn't even know that Lagrangian thing existed, plus, it seemed strange to me that it was used there - Lagrange died way before Quantum Mechanics even existed. I'll be happy to learn it from your book :)

    • @tommywhite3545
      @tommywhite3545 5 лет назад +3

      @@baptistebauer99
      Take your time with it I'd say.

    • @johnkross7227
      @johnkross7227 5 лет назад +2

      Love the asylum, great work. could you maybe do a video on faster than light neutrino's? Or Maybe suggest some helpful info sources. Everything I've seen says this phenomenon is a myth but then what is the deal with the super kamiokande neutrino detector. Really hitting a wall here. Any help would be appreciated.

  • @adamroach4538
    @adamroach4538 5 лет назад +828

    6:22
    Sledge hammer:
    x =( -b ± √b²-4ac) / (2a)
    Walnut: x² +2x = 0

    • @99bits46
      @99bits46 5 лет назад +65

      Plier: ∝ +β = -2, ∝β = 0

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +139

      Accurate.

    • @IslandC0der
      @IslandC0der 5 лет назад +4

      Nice one. xD

    • @non-inertialobserver946
      @non-inertialobserver946 5 лет назад +19

      @Hassan Khan yup, except you forgot a square root √

    • @adamroach4538
      @adamroach4538 5 лет назад +10

      @@non-inertialobserver946 no he probably just didnt have a radical on his keyboard like I do so he used a solidus😊

  • @kevindaniel8249
    @kevindaniel8249 5 лет назад +754

    Please make a video on Hamiltonian Mechanics!!! Enjoyed this one thoroughly :D

    • @gagan4012
      @gagan4012 5 лет назад +10

      I second this

    • @agassidr
      @agassidr 5 лет назад +8

      Yes please

    • @IqbalHamid
      @IqbalHamid 5 лет назад +7

      You got my vote too! You will definitely guaranteed a view from me if you do!

    • @Lucky10279
      @Lucky10279 5 лет назад +19

      Yeah, I'd love that too. I've been asking stuff about QM a lot and people keep mentioning Hamiltonian mechanics, but I don't know anything about it. I'd love a Science Asylum explanation!

    • @MozartJunior22
      @MozartJunior22 5 лет назад +10

      It's exactly the same thing, just with a plus instead of a minus

  • @LaserGuidedLoogie
    @LaserGuidedLoogie 5 лет назад +93

    Great video.
    When I discovered Langrangian mechanics, as a physics major, I was like, "holy shit! my life has been a lie!"
    You feel like a kid who has been playing with alphabet blocks, suddenly learning about literature.

  • @photelegy
    @photelegy 4 года назад +295

    5:39
    1: Does it take every path ...?
    2: No no no, don't be ridiculous!
    Quantum Mechanics: Am I a joke to you?

    • @Lucky10279
      @Lucky10279 4 года назад +11

      Accurate.

    • @Lucky10279
      @Lucky10279 3 года назад +6

      @ Everything is NOT just given. Sure, some introductory physics textbooks will just give a bunch of equations without explaining where they come from, but that's just poor teaching. All of those equations had to be derived and experimentally verified.
      Why is physics complicated? Because its the study of the physical world and the physics world is complicated.

    • @Lucky10279
      @Lucky10279 3 года назад +1

      @ Newtonian physics isn't that complicated, true, but that's the simplest type of physics. Things get a lot more complicated when you move on to things like general relativity, quantum mechanics, etc., in large part because the math required is quite advanced.

    • @Lucky10279
      @Lucky10279 3 года назад +4

      @ I don't know who you're referring to, but why are you assuming that biology and physics can't _both_ be complicated? I don't know much biology myself, but honestly, _any_ major field of study is likely to get complicated -- if it were super simple and easy to understand it wouldn't be something people spent years or even decades studying to understand.
      Furthermore, people have different talents and so some people will find some subjects much easier to understand than others. A topic that seems incredibly complicated and hard to understand for one person may seem quite simple and intuitive to someone else. Heck, there are lots of things that seem really simple and intuitive to me know that I once found really difficult to comprehend.
      Anyhow, just because something gets complicated doesn't mean it's impossible to understand or not worth learning.

    •  3 года назад

      @@Lucky10279 it was just my last ques.

  • @benbedraabdssamad1413
    @benbedraabdssamad1413 5 лет назад +35

    What I like most about lagrangian mechanics is how it treats forces such as surface reaction (normal force) and string tension. Basically, the theory replaces this kind of forces by geometrical expressions called "constraints", which are relations between coordinates or/and velocities that can be determined by the geometry of the situation. This greatly simplifies the problem by reducing the number of coordinates or degrees of freedom.

  • @botondosvath2331
    @botondosvath2331 5 лет назад +54

    It's so great to hear "Principle of stationary action" instead of "Principle of least action" :)

    • @vaanivijay6552
      @vaanivijay6552 6 дней назад

      @@botondosvath2331 how come tho? Why is that?

  • @MonteiroLucas
    @MonteiroLucas 5 лет назад +371

    Look.... Many many times have I praised you before. Don't get tired of it because holy cow...
    Your videos are spectacular. You can explain very deeply, very easily and without losing touch with many many important aspects of science.
    It's a very honest simplification with wonderful results.
    As a physics master and a teacher, I'm always amazed.
    I imagine it takes a lot of hard work from you. So congratulations. Really.

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +84

      So much hard work! I wish I could put out more videos, but they take too long to produce.

    • @MonteiroLucas
      @MonteiroLucas 5 лет назад +20

      @@ScienceAsylum I can only imagine!! But hey... Wanting to be more productive is only natural. Every hard work brings that feeling.
      I, for one, think you release videos in a very good pace. Specially if considering this high quality of content

    • @gumunduringigumundsson9344
      @gumunduringigumundsson9344 5 лет назад +7

      @@ScienceAsylum You can do it! 👍
      I live in my car atm (luxury, station with a mattress and no rent (crazy expensive)) in Reykjavik cuz I nearly went too crazy (also let my underground culture exploit me so I could learn a bit about it how it functions.. de-functions (Its a bad hobby I know trying to save the world but being responsible and seeing it first)) haha but I am ok now just a little crazy (not dishonest) which is the only way to be.
      I still throw 20$ your way on patreon soon my potential friend. I watched your vids for an hour yesterday, its soothing.
      By the way..a favour please.
      I thought a bit about it when I was 14 and came to the conclusion that black holes gain much more mass than what they actually eat in kilograms.. cuz of all the energy (hot hot 'n fast fast) in the mass that it took with it "when" it merged with the singularity.. how am I wrong?
      Thanks for a grrreat channel. I have a bag full of food and going to my secret sober meeting in 1 hour so i'm not "fine" rather I am well and improving haha. Thanks for a great channel.
      Ps. Did you catch what I said two days ago about Han Solo and the kessel run? I made it on the spot in my car and I am a little proud of it if I say so my self.
      Pps. "How can you make as many as possible undestand something as well as possible in the shortest amount of time" is in my opinion the basics for "The science of explaining" is. No professor or teacher or anyone has been able to tell me what that science is called..
      But you are mastering it.
      👊🐶🌎🧙‍♂️👍

    • @gumunduringigumundsson9344
      @gumunduringigumundsson9344 5 лет назад +1

      I hope you do not feel I am oversharing... just telling a bit..
      Thanks.
      By the way.
      The lack of space in my comment obve.. for you to read it well and the extra "is" .. are totally intentional..ehm! (not)👊😂 for my artistic freedom wings of hotness must not be damped with stale perfexion.. ola.
      (I am a trained proofreader (in my language) and I used to make book's texts look good on page and ready for printing g-dangit! (Also only stuck my toes in the jacuzzi of the underground for a few weeks lately --after my wife left in april cuz i drank too much beer (true and we together again) --and i let in the mother of my friend who brought criminals with her that lied to me and I pity them for weeks and helped haha)) Haha!
      Thanks again.. It feels great to share and tell you guys how awesome I think this Youtilube Asylum thing is and them progresses it is proliferating.
      12 minutes until meeting starts..
      Have a good day guys!
      Thank you.
      And now for something completely different.
      In case you missed it.
      Alternatino rules! 😂 ruclips.net/video/1j4rrgr0KeU/видео.html

    • @localverse
      @localverse 5 лет назад +5

      Making things easy isn't easy, especially while holding on to accuracy... and often requires the whole picture while keeping things brief. The result is brilliant simplicity.

  • @swapnilshrivastava6889
    @swapnilshrivastava6889 5 лет назад +82

    It's quite cool of a method actually! I used this once to figure out time period for a simple pendulum and it was an Eureka moment when I actually got the familiar equation. Thanks Nick for the video, it's been a recap!

  • @An0nim0u5
    @An0nim0u5 5 лет назад +166

    I think RUclips is broken... This channel should have well over million subs...

    • @Mohit-ir5xo
      @Mohit-ir5xo 5 лет назад +3

      Rarity of scientists...:(

    • @antoniomaglione4101
      @antoniomaglione4101 4 года назад +2

      The number of RUclips views goes with the spectacularity of a video, not because of its genius content.
      And often goes for gossip or near-libel.
      Some truly informative YT channels spend an insane amount of money just to add some spectacle to the information they deliver. It is funny to my eyes, but necessary for many others.
      And yes, many people learn things by accident. And they forget them by rule. A sad business model...

  • @devapriyan5747
    @devapriyan5747 5 лет назад +447

    I'm not first
    I'm not last
    But when i saw this,
    I clicked fast
    ..
    Fast fast

  • @baab4229
    @baab4229 5 лет назад +15

    Learned this this semester in my theoretical physics course and while I appreciate the mathematical explanation I thought it really lacked the visual image of what's happening. This is why we have youtube and amazing youtubers like you. Thanks for the help!

  • @anujarora0
    @anujarora0 5 лет назад +145

    2:40 There's this farmer, and he has these chickens, but they won't lay any eggs. So, he calls a physicist to help. The physicist then does some calculations, and he says, um, I have a solution, but it only works with spherical chickens in a vacuum.

    • @scottanderson8167
      @scottanderson8167 5 лет назад +10

      Anuj Arora that is a great joke. It’s funny, and it makes you think. But also it doesn’t make you actually laugh out loud so no one thinks you’re a freak

    • @TheRABIDdude
      @TheRABIDdude 5 лет назад +3

      @N/A ...What?
      Why does the scientist turn into multiple scientists on the 4th line? Why do these multiple scientists say "Pulls chicken closer"? Why am I wasting my time scrutinizing the grammar of a crappy worthless comment? Forget this, I'm gonna do my work.

    • @anujarora0
      @anujarora0 5 лет назад +3

      @Cameron McHenry yeah and it's a variation of spherical cow joke

    • @anujarora0
      @anujarora0 5 лет назад

      @Cameron McHenry then click this link en.wikipedia.org/wiki/Spherical_cow

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +6

      @Cameron McHenry I referenced it here in this video: ruclips.net/video/sB1EPGmpzyg/видео.html :-)

  • @B-max.
    @B-max. 5 лет назад +18

    This is the only RUclips channel I have notifications turned on for.

  • @yaswanthpakalapati9994
    @yaswanthpakalapati9994 4 года назад +2

    Bro , when I saw your video for the first time , I thought that may be it was a very famous channel and had millions of subs , just I was too late to notice it . But when saw your subs I was literally shocked . What the quality of your content needs at least 10 million subs .

  • @kripashankarshukla4073
    @kripashankarshukla4073 5 лет назад +3

    This content is really rare only one out of millions of webpages and RUclips videos. Hats off Nick God appreciates your work.

  • @crouchingtigerhiddenadam1352
    @crouchingtigerhiddenadam1352 5 лет назад +17

    Great video! The principle of least action pops up all over the place, I will be sharing this with my family. We're very lucky that you decided to make RUclips videos.

    • @oldhounddog01
      @oldhounddog01 3 года назад

      I try to share science with my wife, guess how that goes :)

  • @nachannachle2706
    @nachannachle2706 5 лет назад +4

    Nick, you have the BEST analogies in the whole Scientific universe.
    Your presentations are 100000 times more accessible to me than Feynman's (supposedly "easy") lectures. Sure, the visuals help, but it is fairly obvious to me that you have an AMAZING ability to pass on knowledge in the most "common sensical" ways. :)

  • @therandomguy99
    @therandomguy99 4 года назад +4

    For the last 6 years now I had no freaking clue what tensors and lagrangians "are" until I watched your vids. TY SO MUCH

  • @patmat.
    @patmat. 3 года назад +2

    I totally get the idea, thank you. As a mechanical engineer (MSc) I think we learned the method as the "principle of lower energy" rather than "Lagrangian mechanics". We write the energy equations and try to find the lowest points, in most cases it leads to differential equations too complex to solve.

  • @jimreinhart9539
    @jimreinhart9539 3 года назад +3

    Wow, Beautiful stuff! The shortest path is sometimes longer. I got my AA degree from Pasadena City College, I can’t tell you how many courses I took over and over. I came back to school years later and got my BFA in painting. A lot is going on and the shortest path is twisted and curved can’t begin to tell you what a strange World it is we live in. Math and Science is Beautiful.

  • @oldhounddog01
    @oldhounddog01 3 года назад +2

    i spent 30 years in college studying science. I thought i was quite good at it. my young niece who was getting her degree in physics brought home a book that was new to me: "Classical Dynamics" which had this topic covered. What a delightful surprise! By the way, while your videos are not as technical as some of the others they are fun to watch and I do pick up 'stuff' by watching them...thanks

  • @pipertripp
    @pipertripp 5 лет назад +13

    This was great! I'm close to wrapping up intro mechanics, which is most definitely all about forces (Euler-Cromer anyone?). It's been loads of fun. Mechanics is a really interesting subject in general, and I'm really keen to see it from different points of view... Lagrange and Hamilton. So yeah, definitely do a video or two on Hamilton's work. Maybe even use Lagrange or Hamilton's technique to solve a "classic" problem that highlights the strength of the approach. Or whatever. Love the channel and thanks for taking the time to share your knowledge.

  • @martovify
    @martovify 4 года назад +2

    1:48 that animation is so beautiful that almost made me cry

    • @ScienceAsylum
      @ScienceAsylum  4 года назад +1

      It's physically accurate too! 🤓 Took _forever_ to render into the video.

  • @ardendarling5613
    @ardendarling5613 4 года назад +6

    I was introduced to your channel today, and I have watched several videos in a row. It's amazing, I haven't felt the same way since I watched Bill Nye the Science Guy as a little kid. You have so much enthusiasm for this, you're willing to fool around and make little jokes, but it adds so much to it that overly serious channels just can't compete with. You have a great understanding of how to communicate complex ideas in a simple way, and you seem to be having quite a bit of fun doing it. It's infectious! Keep up the good work, and stay crazy!

  • @lucasfreitag9794
    @lucasfreitag9794 5 лет назад +21

    I really enjoy watching your videos man. They are so easy to understand, even though the subject seems hard at first sight. You are doing a good job.
    Greetings from a 2nd semester student in Heidelberg. 🙋🏽‍♂️

    • @stefaniasmanio859
      @stefaniasmanio859 5 лет назад

      they ARE difficult and hard... and HE is great making subject that easy

  • @coryscamihorn1811
    @coryscamihorn1811 5 лет назад +8

    "The degrees of freedom," bit got me. I was like, I'm going to subscribe...then remembered I am already subscribed.

  • @rasanmar18
    @rasanmar18 5 лет назад +1

    Lagrangian concepts are not only applicable to mechanics, It applies to any pair of magnitudes that are tied in a similar way to that of energy and work. It can be applied to optimization problems where you can put the restrictions and the function to be optimized in the same equation. Langrange, this guy really blew up the whole thing!!!

  • @nuric91
    @nuric91 5 лет назад +18

    You are the best physic youtuber toegether with PBS spacetime. There PBS has more complex and general topics you go and tell people to look on things more differently. Keep on going pls.

  • @pavlenikacevic4976
    @pavlenikacevic4976 5 лет назад +4

    Alongside with quantum mechanics, Lagrangian mechanics is definitely the topic I had the most fun learning. It's also way less abstract than QM so I could just sit back and enjoy lectures at the uni. Beautiful times

  • @johnm.6975
    @johnm.6975 5 лет назад +12

    I was literally reading about this today at work and I have a much better understanding of it now after having seen this. I’ve been thinking about taking a classical mechanics course at college, but it’s not really a chemical engineering thing haha. I feel like I might do it now just for fun 😝 Thanks

  • @ranam
    @ranam 5 лет назад +2

    THIS IS THE BEST TUTORIAL I HAVE EVER SEEN IN MY WHOLE LIFE MAN U ROCK YOU DONT BELONG TO A AN ASYLUM YOU ARE A GENIUS . CRYSTAL CLEAR EXPLANATION ON LAGRANGIAN MECHANICS

  • @psmoyer63
    @psmoyer63 5 лет назад +6

    Unlike many of the other RUclips programs on physics, your audio quality and levels are consistent and clear throughout your program series, making your content much easier to follow and to understand. Your enthusiasm helps as well on that account.

  • @AndrewDotsonvideos
    @AndrewDotsonvideos 5 лет назад +1

    Path integrals are so intuitive (conceptually) thanks to lagrangians. You have an infinite number of paths that can contribute to an amplitude, but the only ones which minimize the action really contribute since it's proportional to e^{-S} (in imaginary time)

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +1

      Yeah, I'll bring this up when I do the quantum mechanical approach to simple mirror reflection.

    • @AndrewDotsonvideos
      @AndrewDotsonvideos 5 лет назад

      Noice

  • @magicalpencil
    @magicalpencil 5 лет назад +8

    "Just remember, it only seems mysterious because noone understands it" - best quote ever!!!

  • @1111boone
    @1111boone 5 лет назад +1

    The more I watch your videos the more I know how little I understand any of these concepts. Yet, I still like them and enjoy your way of explaining in an entertaining manner!

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +1

      That's not just about my videos. It's just a general principle: The more we know, the more we know _we don't know._

  • @gromajor
    @gromajor 4 года назад +5

    your differenciation of work & energy is absolutely great : very clear and easy to understand. one pedagogy award for you. 👍 🙂

  • @RiteshNEVERUNIFORM
    @RiteshNEVERUNIFORM 2 года назад

    You are the most underrated Physics/Science youtuber I have ever seen. RUclips clearly doesn't know how to respect Science creators

  • @das_it_mane
    @das_it_mane 3 года назад +4

    These are the only videos on RUclips I have to slow down instead of speed up

  • @Smitology
    @Smitology 2 года назад +4

    Idk why but I like to think of Lagrangian vs Hamiltonion mechanics to be like Minecraft speedruns. Lagrangian is a set seed speedrun, where you know everything and you mathematically minimise your path through the world, while random seed speedruns are based on what information you have at the moment, and making decisions based on the current frame of the game.

  • @bytefu
    @bytefu 5 лет назад +30

    Good start, but you barely scratched the surface. An another more in-depth video would really help, especially for understanding the whole configuration space thing.

    • @johnstoner2
      @johnstoner2 5 лет назад +5

      Yeah. This sort of talks about the idea, but I can't make use of it having watched the video.

    • @danielodors
      @danielodors 5 лет назад +4

      That's how his videos are. I'm pretty sure there's tons of rigorous videos out there if you look for them.

    • @stefaniasmanio859
      @stefaniasmanio859 5 лет назад

      Infact we are waiting for the other chapters...

  • @imthestein
    @imthestein 3 года назад +1

    When I was in college working on my physics degree I fell in love with the Lagrangian. It is just so elegant to me

  • @happyrogue7146
    @happyrogue7146 3 года назад +3

    i always wondered why Lagrangian mechanics was the tool for standard model and not Newtonian, now i know. Thanks Nick

  • @hankseda
    @hankseda 5 лет назад +1

    Brief but accurate and informative video on the Lagrangian and the principle of least action. It does a better job than most popular science texts and even textbooks in exposing the essentials. 👍👏

  • @Lucky10279
    @Lucky10279 4 года назад +4

    5:20 "Yes, this a math thing." I can hear the frustration in your voice. I'm guessing a lot of your students at the college got frustrated with the math?
    In your newer videos, since you've switched to youtube full-time you've been much enthusiastic about the math, which lots of people seem to like, myself included. It's awesome that you're able to teach the topics you want to teach, the way you wanna teach them and have people watch the videos because we _want_ to. It's so much more enjoyable teaching people who _want_ to learn.

  • @EventHorizon618
    @EventHorizon618 3 года назад +2

    This explains the principle of least action better than most other videos on the subject.

  • @shilpamali5997
    @shilpamali5997 5 лет назад +81

    Idk how I arrived at the asylum,
    I just know one thing......
    I don't wanna leave this asylum😊😜😜😜

  • @eldersprig
    @eldersprig 3 года назад +1

    Just watched several lectures on yt from a university classical mechanics course. Mostly listened to chalk on the board. This video has a denser amount of information in it. Bravo!

  • @katalyst4stem
    @katalyst4stem Год назад +3

    Let's get 'The Science Asylum' to a million subscribers 🙂
    Relevance of any topic or idea in Science is important and this installment by Nick addresses the relevance of Lagrangian mechanics vs the giant 'Newtonian mechanics'. I have watched all videos on this topic and without any bias, I vote this one as the best 🙂
    Thanks Nick and keep it up ❤
    On a side note, Nick can you throw some light on how you animated the double pendulum @ 2:00 (only if it's not a problem)

    • @ScienceAsylum
      @ScienceAsylum  Год назад +1

      The double pendulum is animated in After Effects, but has Lagrangian mechanics coded into it (so it's accurate).

    • @katalyst4stem
      @katalyst4stem Год назад

      @@ScienceAsylum Thanks for sharing 🙂

  • @stefaniasmanio859
    @stefaniasmanio859 5 лет назад +1

    OMG!!! Super!! Never seen ANYTHING more complete and clearer!!! Thank you so much!!! I met lagrangian transformations somewhere in my past university courses... a deep mistery ! 😳😱😱

  • @philipberthiaume2314
    @philipberthiaume2314 5 лет назад +21

    "I'm a beasssst..." ??!! lol. Now, when I think "beast", I think Nick Lucid.

  • @grt124z7
    @grt124z7 5 лет назад +1

    Currently studying Continuum Mechanics where Lagrangian and Eulerian material formulations are the base of this course. Love your videos.

  • @dude123456787
    @dude123456787 5 лет назад +42

    Man you videos are awesome
    Love from india

  • @MsAlarman
    @MsAlarman 3 года назад +1

    Holy cow! You are a genius transforming tons of equations into visual reasoning. Indeed perfect integration between the right and the left side of the brain!

  • @upendraagnihotri2686
    @upendraagnihotri2686 4 года назад +3

    You make the subject so much interesting to understand that's a very rare quality of yours. Thank you very much, sir.

  • @stefaniasmanio859
    @stefaniasmanio859 5 лет назад +2

    GOT THE BOOK!!! Payment NO PROBLEM (that’s the easy part...) Pdf download NO PROBLEM unzip NO PROBLEM! thank you so much!!!, all the very best from Italy!!!! 🇮🇹

  • @nekomatafuyu
    @nekomatafuyu 5 лет назад +9

    Lagrange makes several good points. 5 of them in fact...

  • @MS-sv1tr
    @MS-sv1tr 3 года назад +1

    I liked the visual aid of assigning a Lagrangian value to every point in space, and then the correct path is the one whose sum of values it hits is least. It's not intuitive that kinetic energy is a function of position. But a conservative force's potential energy is a function of position, and total energy is conserved. So given one value of kinetic energy, you'd be able to assign a value of L to every point in space.

  • @Dmittry
    @Dmittry 5 лет назад +7

    I didn't think about Lagrangian mechanics before. Now I'm thinking about Lagrangian mechanics.

  • @sorrefly
    @sorrefly 5 лет назад +1

    I like the way you always critic your own talking, that means that you really care about what you're saying!

  • @suyashverma15
    @suyashverma15 5 лет назад +4

    Wow great video Nick!!👏👏
    You explained it in an unprecedented way. And I am wondering on the fact that on the macroscopic levels how these two phenomenons, law of least action and law of thermal equilibrium respectively which seems to be the fundamental in nature, are just the result of the more preferred event of Quantum mechanics where these laws can also break but rarely. What you think about it??

  • @SumitVerma-ln5nz
    @SumitVerma-ln5nz 5 лет назад +2

    We want more on lagrangian mechanics!Please !!

  • @deepvybes
    @deepvybes 5 лет назад +3

    Loving the longer vids :D

  • @thrunsguinneabottle3066
    @thrunsguinneabottle3066 3 года назад +1

    The problem for most of us is: "Why choose action?" It is almost a fantasy quatity. In what other context do we come across action?
    I suppose that the fact that kinetic and potential energy were still incompletely understood in Lagrange's day allowed him the freedom to choose an absurd concept: "action". He got lucky. It worked. But for me, it makes no more sense than if he had started with his own inside leg measurement.

  • @moisessalazar4432
    @moisessalazar4432 5 лет назад +3

    Lagrangian mechanics is beautiful,fun and useful.

  • @sketybel1
    @sketybel1 5 лет назад +4

    Ha! I just finished a statistics class and programmed a bunch of algorithms using degrees of freedom in excel. This video helped explain why that data point matters. Bonus points on the fireworks!!

  • @mrl9418
    @mrl9418 5 лет назад +8

    Omg I checked out, he was actually born Giuseppe Luigi Lagrangia.
    I hope I'm forgetting this so I can be astonished again by it.

  • @One-stop_destination
    @One-stop_destination 3 года назад +1

    Presentation style is great ..Easy to understand than other videos on same topic...Enjoyed this one thoroughly!

  • @RazorBaze
    @RazorBaze 5 лет назад +7

    Wow, man
    u deserve so much more subs

  • @shayanmoosavi9139
    @shayanmoosavi9139 5 лет назад +1

    Wow. Lagrangian mechanics is so cool. I think it's mentioned in my analytical mechanics course which is the next semester. I now at least have an idea of what it is before I deal with it. You teach very complicated stuff so easily and your way of animating stuff helps a lot to visualize things.

  • @TheAmbientMage
    @TheAmbientMage 5 лет назад +4

    I never thought about modeling degrees of freedom as a cartesian axis. That's nifty. I have to think about that more.
    I pick up so much from these videos that aren't even the focal points. So awesome.

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +2

      Yep! In fact, the path the red dot takes at 7:12 is the path we're _actually_ using in the principle of stationary action. Lagrangian mechanics is done in configuration space.

  • @ijfoij3oijf8jfoi3jfjfjio7
    @ijfoij3oijf8jfoi3jfjfjio7 5 лет назад +1

    Love your videos! However, the proper way to define the Lagrangian is using the kinetic co-energy (instead of the kinetic energy, as is stated in the video), because for the Lagrangian the configuration space is the tangent bundle (instead of the cotangent bundle; some nice confusing vice versa naming to create some extra fun).
    Or put in other words: L(q,q̇) = T*(q̇) - V(q). Where L is the Lagrangian as a function of the generalised displacements (q) and the time derivative of q (q̇, which is also called flow); T*(q̇) is the kinetic co-energy as a function of q̇; V is the potential energy as a function of q. We need to define L using T*, because the kinetic energy (T) is not a function of the flow (q̇), but of the generalised momentum (p): T(p) = p * q̇ - T*(q̇). From which it follows that T(p) and T*(q̇) are only equivalent (i.e., T(p) = T*(q̇)) in the case that there exists a linear relation between p and q̇. Which of course is often true with the relation between momentum (p) and velocity (v) (where x is the displacement) p = m * ẋ = m * v, but not in general.

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад

      That's a bit too "mathy" for what I do on this channel.

  • @rc5989
    @rc5989 5 лет назад +12

    As usual. Fantastic content. However, I must point out that the content leaves the viewer a little bit less crazy after viewing than before viewing. Is this part of the master plan? Ha! Just kidding, of course. Thank you for all you do!

  • @billjensen401
    @billjensen401 4 года назад +1

    I wish this video was available during my engineering program at Penn State back in the 80s, it would have helped me so much.

  • @kobiromano6115
    @kobiromano6115 4 года назад +4

    Hahaha PBS SpaceTime T-Shirt! "I'll science anything I want"... I have it too :D

  • @eriknystrom5839
    @eriknystrom5839 5 лет назад +1

    I love it. Lagrangian is perfect for the motion of planets and satellites ( ==> Kepler’s laws) and the Coriolis Effect.

  • @bhooshansawant3722
    @bhooshansawant3722 5 лет назад +3

    I just love your every video as you teach in a funny way like you just give infotainment..👍👍

  • @IqbalHamid
    @IqbalHamid 3 года назад +1

    @08:00 You have here, just provided an enlightened intuition of "action". I never thought about it this way but I like your description of action as the amount of *"VARIATION"* between KE and PE (along the path being considered); hence L = T *MINUS* V

  • @radix4801
    @radix4801 5 лет назад +12

    "Nobody lives in a vacuum!" Not for very long, anyway.

    • @traininggrounds9450
      @traininggrounds9450 5 лет назад

      It wouldn't be living though. But its just saying that we all hear the same music and see the same colors. Truth is what we are sustained by.

  • @IllIl
    @IllIl 2 года назад +1

    Thank you! I seriously appreciate the way you explain things while emphasizing that it's a model or way of thinking about things. Other explanations that seem to invoke some metaphysical interpretation of reality just make the raw _thing_ more difficult for me to understand.

  • @adamroach4538
    @adamroach4538 5 лет назад +7

    1.5k likes 6 dislikes? Wow, I've never seen that ratio before.

    • @NailOriginal
      @NailOriginal 5 лет назад +1

      Adam check out
      Artikel 13 - Dieses Chaos haben wir jetzt! RA Solmecke (50 min Video)
      it has a 28k vs 200 ratio.

  • @andromeda121
    @andromeda121 5 лет назад +1

    Why is this channel not blown up yet?

  • @uesdtosignin1038
    @uesdtosignin1038 4 года назад +4

    0:43 You forget statistical mechanics.

  • @mouseaviator3672
    @mouseaviator3672 5 лет назад +1

    Amazing channel, I'm glad I found this channel that covers many questions that people have, and breaks everything down into the very basics. Keep the videos coming!

  • @playgroundchooser
    @playgroundchooser 5 лет назад +4

    Am I the only person that gets ever so slightly disappointed when we don't get any FAST FAST items in a video? 😄

    • @old888
      @old888 5 лет назад

      Yes

    • @old888
      @old888 5 лет назад

      You are
      Patience....

  • @schematism
    @schematism 3 года назад +1

    Wow wow wow! You have explained in few seconds what is a phase space! You are a genious!

  • @muhammedalthaf_phy1866
    @muhammedalthaf_phy1866 5 лет назад +4

    Hiy nick your type of explaination is so very understanding and so nice and i liked it well you .
    I have a small doubt if black holes are explained by swarchild radius can every matter turned into black hole ...

    • @muhammedalthaf9191
      @muhammedalthaf9191 5 лет назад +3

      Thats correct

    • @ashiknoushad2522
      @ashiknoushad2522 5 лет назад +3

      Yeah nick is a good lectrurer

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +1

      Yes, anything with energy can turn into a black hole under the right conditions (including light).

    • @KohuGaly
      @KohuGaly 5 лет назад +1

      @@ScienceAsylum I disagree. Objects with rest mass lower than planck mass can't turn into black holes, because they don't fit within their own Schwartzshild radius.

    • @muhammedalthaf_phy1866
      @muhammedalthaf_phy1866 5 лет назад +1

      @@KohuGaly thats a fact

  • @mohammedal-haddad2652
    @mohammedal-haddad2652 5 лет назад +2

    All I have learnt about dynamics and related mathematics has been put into perspective by this video. Thank you very much.

  • @rahmatabadi3839
    @rahmatabadi3839 5 лет назад +2

    Could you make a video explaining how electrons flowing through the filament of an incandescent light bulb produce photons?

    • @sp101k8
      @sp101k8 5 лет назад

      Friction

    • @rahmatabadi3839
      @rahmatabadi3839 5 лет назад +1

      @@sp101k8 It mainly has nothing to do with friction (IMHO).

  • @fordfactor
    @fordfactor 5 лет назад +2

    From what I understand, Lagrange based his mechanics on an idea from d'Alembert about virtual work. The principal of virtual work is another time-saving physics concept which gets messed up too; I'd be interested on your take on that one (not that you're not busy or anything).

  • @GenghisVern
    @GenghisVern 5 лет назад +3

    I use a sledgehammer to open most everything. But in everyday calculations, like when I start throwing things, I think Newtonian mechanics are more than adequate.

    • @kenlogsdon7095
      @kenlogsdon7095 5 лет назад +1

      Yeah, well.... When the only tool you have is a hammer, all problems begin to resemble nails....

    • @GenghisVern
      @GenghisVern 5 лет назад

      @@kenlogsdon7095 never underestimate the power of Newtons.. by the sleeve

    • @firstlast9251
      @firstlast9251 5 лет назад

      Vern Etzel idk, IMO Lagrangian mechanics is easier to use but it doesn’t give you that feel for the question that you have when you use Newtonian mechanics

    • @GenghisVern
      @GenghisVern 5 лет назад

      @@firstlast9251 that's from a ZZ Top tune, right?

    • @firstlast9251
      @firstlast9251 5 лет назад

      @@GenghisVern o no, did i accidentally make a reference to something lmao

  • @samuelowens000
    @samuelowens000 5 лет назад

    This is the first channel I've willingly watched ads for. This channel is amazing!

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +1

      Whenever someone comments this, I say this: *Don't watch (AND DEFINITELY DON'T CLICK ON) ads you're not actually interested in.* The amount of money I make from them is _so small._ It isn't worth your time. All it really does is make Google's ad algorithm think you're interested in whatever product/service the ad is providing, which makes it serve you that kind of ad more often. *Sharing my videos if you have friends you think might like them does a lot more for me than watching an ad.*

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад

      I appreciate your enthusiasm though 😊👍

  • @ayushmaan_sharma
    @ayushmaan_sharma 5 лет назад +5

    8:20 Lagrangian Mechanics is so powerful that Quantum Mechanics 0:48 also uses it

  • @alkismavridis1
    @alkismavridis1 5 лет назад +2

    Awesome video. You reminded me my studies in the university of Athens, years ago.
    Learning lagransian/Hamiltonian mechanics (along with Noether theorem, of course )was one of the most mind-blowing things that happened to me.
    I can compare the feeling with the one when I leart about Incompleteness theorems, quantum mechanics, or the theory of evolution.
    Thanks a LOT for you great work!
    PS: A video about Noethers theorems on symetries would be a great idea, I think :)

    • @ScienceAsylum
      @ScienceAsylum  5 лет назад +1

      I did a video on the history of Noether's theorem a while ago: ruclips.net/video/ahf0zCaqrwM/видео.html but I'm hoping to go into more detail soon.

    • @alkismavridis1
      @alkismavridis1 5 лет назад +1

      @@ScienceAsylum wow. You are the best! I will watch it out, thanks!

  • @froop2393
    @froop2393 5 лет назад +3

    when classic physics is compressed into one single equation 😀

    • @jaimeaguileradiaz8843
      @jaimeaguileradiaz8843 5 лет назад +1

      And not only classical. Quantum field theory relies on the quantization of "field" lagrangians. That means, also modern theory of physics uses lagrangian mechanics to arrive important results :D

  • @proteus5
    @proteus5 4 года назад +1

    3:02 Contrary to popular belief, Fermat's Principle does not say that light will always take the minimum time path, it says it will take a path where the "first order variation" (ie, first derivative) is zero. Grad students in seismology get this pounded into them because there are cases where the travel time is a maximum, not a minimum. That would be a good topic for a followup video.

    • @ScienceAsylum
      @ScienceAsylum  4 года назад

      Yeah, I expand the definition at 5:03 for Lagrangian mechanics to include maximums, etc.

  • @GottfriedLeibnizYT
    @GottfriedLeibnizYT 5 лет назад +3

    Both.

  • @debajyotimajumder472
    @debajyotimajumder472 5 лет назад +1

    I am a Physics graduate, I found it helpful....... Thanks.....

  • @maxoobbxxx8032
    @maxoobbxxx8032 3 года назад +28

    ibn Al-Haytham is the original gangsta

  • @jacks6910
    @jacks6910 2 года назад

    This channel has been slowly winning me over, this video made me a fan though, this was very well done.