Geodesics and Relativity

2024 ж. 22 Мам.
224 743 Рет қаралды

Why does the Moon orbit the Earth? What's the connection between a funnel and a black hole? What is a metric? All these answers in 11 minutes!
0:00 - Introduction
0:45 - The metric
3:54 - Geodesics
6:29 - Spacetime
10:13 - Conclusion
This video is narrated by Octave Masson.
For more videos, subscribe to the KZhead channel : / scienceclicen
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Alessandro Roussel,
For more info: www.alessandroroussel.com/en
_________________________________________________
ScienceClic Français : / scienceclic
ScienceClic Español : / scienceclices
_________________________________________________
To learn more :
en.wikipedia.org/wiki/Geodesic
en.wikipedia.org/wiki/Spacetime
en.wikipedia.org/wiki/Metric_...

Пікірлер
  • I’ve found myself sharing your videos with physicists of all levels of expertise-from beginning students to long-time professors. Your videos are not only a gift to students, but they are also an inspiration to anyone interested in physics pedagogy. I hope you enjoy making these videos as much as we enjoy watching them.

    @StevenG22@StevenG222 жыл бұрын
    • I do enjoy making these videos a lot, it's a dream come true for me to be able to do them full time as my job! Very glad you like them, and thanks for the support 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
    • @@ScienceClicEN You're a legend! keep it up and I hope the channel continues to grow strong!

      @FatBoyEntertainment@FatBoyEntertainment2 жыл бұрын
    • @@ScienceClicEN these are the gifts that keep on giving

      @PATCHEZinSPACE@PATCHEZinSPACE2 жыл бұрын
    • @@ScienceClicEN I can only second the OP. Your videos are leagues above similar content creators - and they're not bad. You're an amazing educator.

      @TheMindProjection@TheMindProjection2 жыл бұрын
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      @manicmadpanickedman2249@manicmadpanickedman22492 жыл бұрын
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    @Badmanxl5@Badmanxl52 жыл бұрын
  • Favorite science channel on the site honestly

    @davidthelong2154@davidthelong21542 жыл бұрын
    • 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
    • Amazing dimensionality of complex topics simply explained. ^.^

      @TheMemesofDestruction@TheMemesofDestruction2 жыл бұрын
  • Yay! I'm biologist and im learning distance metrics, including geodesics as a part of a proyect that involves tensors and n-dimensional spaces of proteins. With this video I get a clear view about geodesics

    @gama3181@gama31812 жыл бұрын
    • Glad it could help you!

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
    • since you studying this...... is this guy correct...... kzhead.info/sun/hJVxZa2mp4GEfmw/bejne.html

      @theunknown1426@theunknown14262 жыл бұрын
    • You need an English 1 class. pure and simple.

      @dustysavage1187@dustysavage11872 жыл бұрын
    • @@dustysavage1187 Not everyone is a native English speaker, and science is done in other languages as well.

      @photonicpizza1466@photonicpizza14662 жыл бұрын
    • This sparked my curiosity. Can you share a reference for your project and other related concepts of differential geometry applied to biology? Thanks in advance

      @LukasKaitei@LukasKaitei2 жыл бұрын
  • It is insane how well presented your videos are. Please keep this up! :)

    @Maxi-qr5eg@Maxi-qr5eg2 жыл бұрын
    • Thanks!

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • You're the Geodesic to my Relativity, ScienceClic

    @justind7029@justind70292 жыл бұрын
    • Haha thank you very much, glad you like them 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • I love that you explain the concepts clearly enough for most everyone, but also include the equations for those who wish to go further. Thank you for being "au-dessus de ma tête, mais pas hors de portée" (above my head, but not out of reach).

    @WilliamDye-willdye@WilliamDye-willdye2 жыл бұрын
    • That's a very interesting saying. I'll be quoting you on that 😁

      @feynstein1004@feynstein10042 жыл бұрын
  • PBS Spacetime: Best topics and explanations but in a monotonous lecture without good graphics Science Asylum: excellent topics average graphics but good humour and interactive... sometimes too "crazy" stylewise Science Clic: Greatest visuals awesome narration...but too infrequent

    @abhir7823@abhir78232 жыл бұрын
    • I understand scienceclic the most 😅

      @zharul8716@zharul87162 жыл бұрын
  • I just watched your entire general relatively series and have never had such a strong understanding of the material. You also addressed how a 5th dimension is not needed to address gravity in your better general relativity model, which had been nagging my understanding of that concept for a long time. I have so far yet to go but feel invigorated to press forward thanks to you. I noticed you've been using the same song on every video for the last several years. I'd be absolutely willing to compose a custom soundtrack for your videos completely free as thanks for the work you do. Feel free to reach out any time :)

    @dutonic@dutonic2 жыл бұрын
  • This is the best Physics channel by far. The concepts are explained in the right amount of detail

    @ckara2284@ckara2284 Жыл бұрын
  • Showing that following the same latitude is not a geodesic is more clear near the poles. Great video.

    @tim40gabby25@tim40gabby252 жыл бұрын
    • You're right, it becomes obvious near the poles where clearly one should turn to keep a constant latitude

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • I just found your channel and I'm blown away by the quality. Videos like yours inspire me to continue grinding through the hard parts of university to one day be able to wholly understand the beauty of the cosmos.

    @dutonic@dutonic2 жыл бұрын
  • You are 3blue1brown of physics 👌

    @Dkk7077@Dkk70772 жыл бұрын
  • This video is simply stunning! I'm amazed at how well you've condensed these equations and how intuitively you've explained them. I hope your channel absolutely explodes in popularity. Great job :D

    @IntegralMoon@IntegralMoon2 жыл бұрын
    • Thank you very much 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • This channel knows the geodesic to my heart

    @NikHem343@NikHem3432 жыл бұрын
  • The gravity of this channel will not allow me to leave. Bravo.

    @cheddarnutt@cheddarnutt2 ай бұрын
  • Alot of this knowledge I've already viewed in other videos, but the clear step by step breakdown is a joy to watch/listen to. Great content!

    @michaelharipersad9882@michaelharipersad9882 Жыл бұрын
  • The giant connection with relativity at 6:14 blew my mind. These videos help me so much understanding general relativity because of it's excellent visual and audio information. Excellent channel!

    @technologystrong5190@technologystrong51902 жыл бұрын
    • I was actually left speechless at that moment.. I had to pause the video. Amazing.

      @knapton118@knapton118 Жыл бұрын
  • By far, ScienceClic is the most precise on the subjects of physics in the internet. Keep up the good work.

    @mohammaddashtpeyma8369@mohammaddashtpeyma83692 жыл бұрын
    • Mind if i give you some scientific YT-Recommendations?

      @nenmaster5218@nenmaster52182 жыл бұрын
  • Incredibly well explained and the visuals make it crystal clear. Thank you very much.

    @flochforster22@flochforster222 жыл бұрын
  • Please keep these videos coming. The narrative is so awesome and clear-

    @AriannaEuryaleMusic@AriannaEuryaleMusic2 жыл бұрын
  • I just LOVE your visualizations... They are clarifying so many things a textbook or a simple PowerPoint presentation can't really answer. Thanks for all the effort! Your channel is one of my favorite physics channels.

    @thenephilim9819@thenephilim98192 жыл бұрын
    • Mind if i give you some scientific Recommendations?

      @nenmaster5218@nenmaster52182 жыл бұрын
    • @@nenmaster5218 Of course not ... Please go for it 🤗

      @thenephilim9819@thenephilim98192 жыл бұрын
    • @@thenephilim9819 How about Sci Show, Professor Dave, Sci Man Dan, Tier Zoo, Hbomberguy and more-if-you-want then?

      @nenmaster5218@nenmaster52182 жыл бұрын
    • @@thenephilim9819 Rephrasing this: How about Sci Show, Sci Man Dan, Joe Scott, Tom Scott and nile Red? But if we expand the defintion to channel that entertain with science and/or knowledge and/or education, then lemme name many who took what Youtueber 'Oversimplified' did and evolved it. Tier Zoo, Hbomberguy and Bluejay are all great examples for this, just like CGP Grey. I wouldnt call them Science-KZheadrs, but they do the same as the Best of such: Teach via Humor.

      @nenmaster5218@nenmaster52182 жыл бұрын
  • You did magnificent job to explain General Relativity. Although books plays important part in course but your work has reduced the time and energy of learner which he or she have to spent during Reading. I could understand importance of Riemann Geometry in General Relativity only beacuse of your videos

    @kanwarphziks@kanwarphziks2 жыл бұрын
  • As usual, on point presentation and brilliant visualizations. In particular, with the image of the apple moving through space time it's kinda fun to imagine yourself doing that while being pushed *away* from your geodesic by the chair you're sitting on. This is quite different than the usual notion of being *pulled* down by the earth, but more accurate.

    @IncompleteTheory@IncompleteTheory2 жыл бұрын
  • Absolutely stunning videos. Just keep making them!

    @markovesovic6018@markovesovic60182 жыл бұрын
  • Always brillant. I look forward to your videos. Thank you for the time and effort to make these animations. 😊

    @chippotter7204@chippotter72042 жыл бұрын
  • Incredible quality. Just amazing.

    @StarsManny@StarsManny2 жыл бұрын
  • I get excited every time you upload

    @cruuvoshirin5580@cruuvoshirin55802 жыл бұрын
    • Me too

      @ummekulsummasuma3575@ummekulsummasuma35752 жыл бұрын
  • To the author of the video: hi! I watch the videos late at night, and the full white screen actually made my eyes water up, and hurt. I thought you could actually invert the colors, and the video would still work and look great, and it wouldn't be so hurting on the eyes. Thank you for the great videos! I subscribed and clicked on the bell 👍

    @H-var@H-var Жыл бұрын
  • I was literally arguing with my friends about the path a plane takes, yesterday. Great video and thanks! Now I can refer them here.

    @beabzk@beabzk2 жыл бұрын
  • Yes! You finnaly back, LOVE your content

    @hiiamjustacoolrandomuser168@hiiamjustacoolrandomuser1682 жыл бұрын
  • Thank you! These are very informative and extremely well-designed illustrations!

    @bardiashahrestani8564@bardiashahrestani85642 жыл бұрын
    • Mind if i give you some scientific YT-Recommendations?

      @nenmaster5218@nenmaster52182 жыл бұрын
    • @@nenmaster5218 Go ahead! just leave out kurtzgesagt and PBS as I already know them.

      @bardiashahrestani8564@bardiashahrestani85642 жыл бұрын
    • @@bardiashahrestani8564 No problem, i can work with you having good taste anyway! How about Sci Show, Sci Man Dan, Joe Scott, Tom Scott and nile Red? But if we expand the defintion to channel that entertain with science and/or knowledge and/or education, then lemme name many who took what Youtueber 'Oversimplified' did and evolved it. Tier Zoo, Hbomberguy and Bluejay are all great examples for this, just like CGP Grey. I wouldnt call them Science-KZheadrs, but they do the same as the Best of such: Teach via Humor.

      @nenmaster5218@nenmaster52182 жыл бұрын
  • Best visual learning channel on KZhead hands down

    @numkins3724@numkins37242 жыл бұрын
  • This channel is pure quality. Simplicity at its finest. Thank you very much for entertaining us.

    @bitkurd@bitkurd2 жыл бұрын
  • S.C.E I'm always working when you're uploads come up, just saying that I appreciate this channel as much as people who comment earlier than me

    @whirledpeas3477@whirledpeas34772 жыл бұрын
  • Superbly done! Thank you.

    @alisaiterkan@alisaiterkan2 жыл бұрын
  • Awesome video, as always! Thank you!

    @mimArmand@mimArmand2 жыл бұрын
  • That part about a falling apple is simply superbly described.

    @maximumkillmtg@maximumkillmtg2 жыл бұрын
  • Amazing as always!

    @DamnYou04@DamnYou042 жыл бұрын
  • I love your videos! Thank you for your hardwork and creativity 🥰

    @sammalvs@sammalvs2 жыл бұрын
    • Thanks 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • Thankyou for Expanding my mind and Appreciation of Source xx

    @gracemcnamara4470@gracemcnamara44702 жыл бұрын
  • Really cool! Very insightful!

    @kavalkid1@kavalkid12 жыл бұрын
  • Genius, Geeez I would love to have such presentation 30+ years ago! Animation and modeling is superb! Thank you!

    @sercatum@sercatum2 жыл бұрын
  • Yay, welcome back ScienceClic!

    @aidarosullivan5269@aidarosullivan52692 жыл бұрын
  • Oh my goodness I just love it when I hear that music because it tells me I'm about to learn something incredible and this time was no exception I loved every second of it. The music just gives me goosebumps I love it so much.

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    @DragonKingGaav@DragonKingGaav2 жыл бұрын
  • Marvelous video, as usual!

    @andreadelcortona6230@andreadelcortona62302 жыл бұрын
    • Thanks!

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • Thank you for all the efforts, It totally worth subscribing this channel!

    @NishanGhoshgameshamelame@NishanGhoshgameshamelame2 жыл бұрын
  • Only here every phisics topic become understandable and accessible to everyone. That's very unique.

    @inugget2557@inugget25572 жыл бұрын
  • Amazing as always. I can't wait for more 😍😍

    @feynstein1004@feynstein10042 жыл бұрын
  • Love all of these videos!

    @MexMX@MexMX2 жыл бұрын
    • Thanks :)

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
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  • This wonderful article is smooth and gentle, the very best way to wade into cold water...😎

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  • Thank you, this is superb. It's going to be shared.

    @ryantennyson7562@ryantennyson75622 жыл бұрын
  • Wonderful class.

    @marcelob.5300@marcelob.53002 жыл бұрын
  • I love this channel. I just realized I saw this but I’m watching it again….

    @Jaggerbush@Jaggerbush2 жыл бұрын
  • I think it's worth mentioning that two identical objects moving in curved space-time with the same starting point will follow different geodesics depending on their initial speed. I mean, it's kind of obvious that objects thrown at different speeds will end up in different places, but it also seems really counter-intuitive that your "forward" direction depends on what speed you have. In space, the forward direction that you see with your eyes, which is actually a direction of a light-speed geodesic, is different from the forward direction you are moving.

    @higztv1166@higztv11662 жыл бұрын
    • Exactly, that's a good thing to keep in mind : geodesics are not straight lines in space, but in spacetime. Hence not only they depend on your initial direction in space, but also your initial direction in time (i.e. your initial speed).

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
    • Isn’t that because No two objects, identical or not can be in the same starting point at the same time in space, so would have to follow a different geodesic. Basically no two objects can ever have the same starting point or be in the same place, so isn’t it a given that it’s going to follow a different geodesic because it will be in a slightly different position.

      @ergyst@ergyst2 жыл бұрын
    • @@ergyst but two objects can be on geodesics that look identical, if the objects have the same starting position and the same speed. They take the same path through space, but are phase shifted only in time? The geodesic are parallel in that case?

      @gamingnscience@gamingnscience Жыл бұрын
    • @@gamingnscience can’t even remember what point was about bro I was high af

      @ergyst@ergyst Жыл бұрын
  • This is amazing stuff. Thank you for visualizing some of these difficult concepts. Honestly I think that schools should talk about this stuff when they are talking about Newton's First Law. If we all were taught that the "straight line" that Newton talks about is (spatially) what is being curved by gravity people would probably have a better understanding what is going on. Explaining the time dimension would then be a little be easier.

    @TerranIV@TerranIV2 жыл бұрын
  • Great video, as usual. Ants and geodesics, cool!

    @PSG_Mobile@PSG_Mobile2 жыл бұрын
  • I wish I saw this before my cosmology course. Great video!

    @Roflia1@Roflia19 ай бұрын
  • Great job, once again!

    @bernardheathaway9146@bernardheathaway91462 жыл бұрын
  • Very Valuable Science video 👍👍👍

    @prabanjan.pkavaskar.p7449@prabanjan.pkavaskar.p74492 жыл бұрын
  • All videos are awesome And explanations are like Cristal clear.. Plz make a project on higgs field and higgs boson. Thanks 👍🏻

    @jasondashiell9262@jasondashiell92622 жыл бұрын
  • Well explained as always 😊

    @andreasreich3933@andreasreich39332 жыл бұрын
    • Thanks!

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • Like it how the music changes suddenly ❤.. very nice explanation 🫵🏼👍🏼

    @rigel978@rigel97811 ай бұрын
  • I think these sort of visualizations are the best way to help people understand the latest scientific understanding of space and time. I'd love to see you cover the visualization of Earth's gravity field (including the field inside the volume of the Earth).

    @TerranIV@TerranIV2 жыл бұрын
  • You are awesome man! Thanks a lot!

    @freddylesca6355@freddylesca63552 жыл бұрын
  • great explanation

    @usama57926@usama579262 жыл бұрын
  • Great videos for learning about physics.

    @brandoncrutchfield5201@brandoncrutchfield52012 жыл бұрын
  • I love how first, it's the happy music, and I think "yes, two ants walking around, I get that, everything's good..." and then suddenly the music changes....

    @Tom_Quixote@Tom_Quixote2 жыл бұрын
  • Your voice is something else mate, there's not a lack of physics or math channels but honestly the way you speak sets you apart, same reason Mat from PBS has a lot of success aswell, keep at it

    @joaoramos2713@joaoramos27132 жыл бұрын
  • My fav KZhead channel. ❤️❤️

    @dyroc@dyroc2 жыл бұрын
  • This video is, as always, really great!! Keep it up! Any plans to make a video on quantum chromodynamics?

    @andreacosta2238@andreacosta22382 жыл бұрын
    • I would like to see QCD on this channel as well, since I could sure use some clarification

      @nathanoher4865@nathanoher48652 жыл бұрын
  • After Vsauce and Veritasium, i find your channel more interesting and understandable.

    @mellowmood9@mellowmood9 Жыл бұрын
  • Very very interesting topic!

    @Sidsidsids@Sidsidsids2 жыл бұрын
  • Great video!

    @albertods611@albertods6112 жыл бұрын
  • I've been learning more about non-euclidean geometry in order to gain a richer perspective of the human body. I have an interest in computational patternmaking for clothing design, and I found this. Simply put: My mind is Blown.

    @arcaetype@arcaetype Жыл бұрын
  • This is another in a series of amazing, sophisticated, elegant, accolade-deserving videos that ought to receive recognition beyond just the KZhead platform. That said, we were determined to find something to be nitpicky about, so here goes 😂 : “…when an apple falls off a tree from a previously motionless state….” **technically speaking** the apple hanging from the tree was subject to a force and therefore already in motion. “…it is because the curvature of spacetime bends the geodesics between time and space…” Well again, **technically** the apple wasn’t on a geodesic to begin with; being held up by the tree meant it was subject to geodesic deviation. There isn’t also really spacetime curvature in this small of a region. The ground is just an accelerated observer; the geodesic paths on his/her spacetime diagram appear to be bending as a consequence of that acceleration. (For there to be spacetime curvature in the vicinity, the distance between geodesics on the spacetime diagram would have to be changing - but even the down-diving lines maintain regular spacing.) However that statement does apply in the global sense, since without curved spacetime there wouldn’t be the gravitational force there to begin with. It’s very encouraging and inspiring to see videos of this quality and caliber out there - please keep it up!

    @dialectphilosophy@dialectphilosophy2 жыл бұрын
    • Thanks! Yes you are completely right, this video was actually made in 2018, if I had remade it recently I might have changed some of the formulations

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • Thanks for the info

    @physicsstudent3176@physicsstudent31762 жыл бұрын
  • Thank you!! I've been waiting to death for new clip

    @apk8452@apk84522 жыл бұрын
  • Thank you! Your videos are amazing!

    @GabrielLima-gh2we@GabrielLima-gh2we2 жыл бұрын
    • Mind if i give you some scientific YT-Recommendations?

      @nenmaster5218@nenmaster52182 жыл бұрын
  • i have no idea if at the end you were just flexing that you can pronounce that but it doesn't matter, these videos are amazing

    @arkanon8661@arkanon86617 ай бұрын
  • This is a good video! Thanks !

    @juancamilohernandezcarrill2438@juancamilohernandezcarrill24382 жыл бұрын
  • superb video pure class,, man please continue to upload,, never stop🙏❤

    @surojpaul14@surojpaul142 жыл бұрын
  • Thank you so much! Is there any chance to have an introductory video about noncommutative geometry in physics?

    @Simone.italia@Simone.italia2 жыл бұрын
  • Please just let the animation of the apple get to the ground. Everything is so perfect, just add a little more time to some of these satisfying animations. People love watching satisfying stuff.

    @jaedong1@jaedong12 жыл бұрын
  • I love your content

    @Jayderzomb@Jayderzomb2 жыл бұрын
  • Very nice animation.

    @mosab643@mosab6432 жыл бұрын
  • Thank you!

    @TheMemesofDestruction@TheMemesofDestruction2 жыл бұрын
  • Very important video !

    @WonderOfNature1234@WonderOfNature12342 жыл бұрын
  • Being waiting for you guys to drop a new video👍🤩

    @DemonetisedZone@DemonetisedZone2 жыл бұрын
  • Your are just mind blowing

    @mohsinaliansari3441@mohsinaliansari34412 жыл бұрын
  • Great as ever!

    @apk8452@apk84522 жыл бұрын
    • Thanks 🙏

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • 2:03 Metrics *do not* give you a grid as represented, tangent spaces do. Metric just gives you a scalar product of vectors in tangent spaces, which can differ at each point of a manifold. And as you presented in a video - in case of immerged manifolds and induced metrics - this has a perfect meaning of distances on a sphere.

    @egoreremeev9969@egoreremeev99692 жыл бұрын
    • The grid does lie in the tangent space, but it is not given solely by it but by the metric. With this "grid" I was referring to normal coordinates, which are derived from the metric, and which are a way to define local cartesian coordinates on the tangent space, and hence allow one to measure lengths and angles with the standard Pythagorean theorem (or Minkowski metric for spacetime). But yes technically the metric is a scalar product on tangent spaces, I didn't want to go in too much technicalities in this videos, my point was mainly to say that the metric is what allows us to measures distances and angles.

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
  • It's funny, I already studied this in uni, and I have good understanding of everything you mentioned, but I still enjoyed watching the video.

    @MooImABunny@MooImABunny Жыл бұрын
  • Thank you.👍

    @-JA-@-JA-2 жыл бұрын
  • I remember having trouble calculating Riemann tensors in high school! KZhead was only a year or two old then! It’s never been easier and more accessible now to autodidact STEM education, even if you have subpar teachers!

    @nat5112@nat51122 жыл бұрын
  • Loved it❤️

    @omidkushani7904@omidkushani79042 жыл бұрын
    • Thanks!

      @ScienceClicEN@ScienceClicEN2 жыл бұрын
    • @@ScienceClicEN Please make a video on particles spin🙏 thank you.

      @omidkushani7904@omidkushani79042 жыл бұрын
  • Another beautiful explanation that even a layman can understand. This is gr8 ability of you. Each video is very thoughtfully crafted. 👍🏽🙏🏽. Keep posting such gr8 work. Can you plz explain the details of formulae you showed in the video. That ll still further open up mind.

    @shantanuaphale3966@shantanuaphale39662 жыл бұрын
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