How to faithfully represent general relativity ? Is the image of the rubber sheet accurate ? What is the curvature of time ? All these answers in 11 minutes !
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Alessandro Roussel,
For more info: www.alessandroroussel.com/en
_
To learn more :
en.wikipedia.org/wiki/General...
Some answers to the questions I have been asked: - Has this visualization not already been presented? No I don't think so : you may have already seen a visualization with a distorted 3D grid (like at 5:20), but the crucial point that distinguishes my new representation is its temporal dimension. It is the fact that the grid is perpetually contracting which allows us to better understand the way bodies fall (and which is more faithful to the equations). As far as I am aware this has never been represented in this way, surely because this is only possible with the video format. EDIT: I have since then discovered that this visualization does exist, at least a similar one called the "river model". It allows for an intuitive understanding of black holes for instance. - If space contracts, shouldn't there be an accumulation of space in the center? Beware no, it is not space which contracts : it is only the straight lines (geodesics) which get closer to each other due to the curvature of spacetime. In the same way that on the sphere the geometry does not change (see at 9:10) , the geometry of space-time is static, it does not vary. But this geometry gives a tendency for straight lines to come closer to the center - How to define a temporal speed? In relativity there are two different times: the time of the observer (the coordinate time / the time dimension), and the time of the object (proper time). Velocity in relativity is the derivative of the coordinates with respect to the proper time of the object. The "temporal speed" is therefore simply given by the rate at which the time of the observer passes compared to the proper time of the object. To find out more, check out my series about the Maths of General Relativity
The new representation of the temporal dimension was very helpful for me at least.
The only struggle I had was with the perpetually contracting grid “bunching up” an infinite amount of spacetime at the center of the earth. I’ve understood gravity to be the effect of time dilation with a slower running clock at the base of the Apple than the top. So if the perpetually contracting grid was representative of time - inertial frames of time constantly traveling the geodesic to the center of the earth then it works for me flawlessly
So the moon does not move in circular orbit ? It is just geodesic which are curved . Then this eliminates concept of centripetal force right??? 🙏🙏Pls respond me as I am having this question from a very long time???? I always wonder what happen to centrifugal force if gravity is not force
@@whykoks yeah it's somewhat I was also thinking. Well thanks
this is a very nice explanation but we are dismissing one an important thing. There is no evidence of the curvature of galactic space and time but mathematical computes. And by the way, elastic sheet does not as same as space fabric in effect galactic empty space. The marbels onto elastic sheet are attracked to the center with bigger ball. Unlike planets such as Mercury, Venus and Earth that orbit around the Sun but are not attracked to it. It is the huge difference that suggests elastic sheet doesn't prove anything. Regard!
Can we take a moment to appreciate that Einstein was able to picture this in his head without the 3D models. That's the part that blows my mind!
he did, actually - "first, imagine a desk , full of a rectangular matches grid"
The fact that other scientist understood what Einstein was trying to say without 3D model is actually more mind blowing.
In the 1920's no less...0_0
@@FigNewton36 i sometimes thinks that how Newton would have felt if he were able read about General Relitivity.
@@FigNewton36 weren't there other metric theories of gravitation, like Nordstrom, but they were wrong as many assumed linearity?
03:27 "It is not acceptable to describe gravity *inside* space time, using gravity *outside* spacetime." THANK YOU. YES. This has annoyed me to no end.
SAME
This has driveb me nad for weeks
Same man!
@@itamarteuerstein8531 Sorry to hear about your nads
Einstein is a fraud just like NASA hollywood period.
The feeling of it clicking when you mentioned that even if the apple is sitting still in space, it's still moving at a velocity through time was crazy. I've often wondered how gravity could pull something in, but I hadn't even considered time as a vector of motion. Literally made my jaw drop, thank you
This gets amplified in black holes where time kind of swaps with a spacial dimension so hard making the center of the black hole a direction in time (once you pass the event horizon), it becomes the future. It’s weird but it’s like in weak gravity you can escape the tendency of the future by spatially moving away from the planet for example, while inside an event horizon, no spatial movement can make you go back in time, time is pushing you closer.
@@tvao9010 Let me not think about that.
Come on everybody knows that!
This model deserves a lot more credit and needs to be spread more widely. A lot of people studying general relativity are often troubled with the obsolete and underrepresenting rubber sheet model while others might think there is no problem with the concept which is actually not accurate enough.
This whole idea makes me feel like objects aren’t actually moving in space but rather they’re so massive that they’re pulling space around them. So spacetime is the only thing in motion in my head when I see these visuals.
@@jambi5096how do u explain expansion of the universe then?
@@ElsaIrfan What if something astronomically massive is pulling the fabric of spacetime to one point? Like an astronomically massive “black hole?” Then we perceive that as expansion? Idk I was just explaining how the model made me feel, I didn’t give it much thought.
@@jambi5096 you could be onto something
@@ElsaIrfan Big Bang
The best visualization of something that can't be visualized I ever seen.. Great job.
Thank you very much 🙏
Awesome work! A few years ago i had a similar idea but as i had no skills with video-production and the graphical tools needed for a job like this i never bothered to even try doing anything with my inner picture of this stuff. :P Since that moment i have been speculating on and of how the "flow of spacetime" influence the outer regions of spiral galaxy's in regard to the "Galaxy rotation curve problem". I feel fairly certain that Kepler's laws don't take into consideration the accumulating flow of spacetime inwards in the spiral arms direction and that this allows the higher rotational speed without the predicted "side effects" of solarsystems coming unbound and slingshot out into deep space.
Ditto ! Excellent representation ! I sort of understood this but this helps a bunch to be even clearer !
Enter the Bragn' Sure it does ! Just space itself has properties of magnetic permeability and electrical permittivity that allows light and electromagnetic waves to travel in a vacuum. This video's subject shows more complicated introducting space-time but now, it is just basic physics and has been proven over and over again. It is hard to see clearly though which is why videos like this are so important
No particles necessary
Message for those watching this video at the end of January 2021. I highly recommend you to watch the videos related to “The maths of general relativity”. Believe me, despite being totally ignorant in mathematics, I was able to “visualize” the effects of space-time curvature much more clearly !! This channel deserves an Oscar !!
Also please watch the first video on this channel. That one made everything 'clic' for me, regarding relativity and the speed of light. "We all move at the Speed of Light" kzhead.info/sun/lNlpga6RgIWbZ5s/bejne.html
Challenge accepted
not enough transgender for oscar. lets think of another award.
Deserves Noble
yes, it must be explained to teenager, with Newton theory
That initial marbles on a fabric model is quite popular on the Internet for newbies like me who try to understand space-time curvature. Even though your final model differ a lot from that model, you didn't simply struck it down and put yours forward. Instead, you improvised it step by step and concluded with your model. This avoided unnecessary confusiom. Thanks for doing that. Really appreciate your work.
I've always found the elastic cloth visualisation problematic and was very happy to see that someone made a better explanation. Thanks for sharing ☺️
Relativity has never been proven. There's a reason it's still called theory. No matter how much you add photoshop and CGI: it's all a hoax
I was exactly gonna say this. I always had to transform that 2D representation to 3D in my head.
Yeah me too
for real tho it only created confusion for me i was more or less trying to imagine this but couldn't due to lack of proper concentration
Same, it just seemed too 2D
I've been trying to find an explanation like this for years. The usual demonstrations in school using 3D distortions of a 2D plane never sat right with me. Thank you for this!
I always thought that the 2D plane illustration was overly simplistic where you'd have to visualize that it was actually happening in 3D. However I didn't understand the time component. I knew time is the fourth dimension, but didn't understand the role it plays in gravity.
Same. This doesn't do it for me either.
I was going to write the exact same comment. thank you too.
Agree 100%
Same it doesn't sit right to me either
High five to everybody who ended up here thinking the marble on a rubber sheet explanation just didn't quite cut it ✋ And great video. Glad to see it's how I imagined it to be :)
🤚,I have always felt that and found the answer only today.
hahaha ✋
🖐️
There's a science museum where I grew up that has a big metal depression you can throw marbles into to supposedly demonstrate spacetime. I remember as a kid telling adults that didn't explain anything, and those adults confidently bullshitting that it was a great learning demonstration.
Exactly. I'm glad he mentioned how gravity is used to explain gravity. That's was an instantly recognizable flaw to me.
YOU ARE A STAR! I was taught the theory in college but never understood it, and therefore never sat right with me and knew there was a better way to explain it and that i was missing. and now 2 decades later, your explanation and visualization makes it all fit together. THANK YOU!!
I didn't understand
@majdsaab 100% agree
This was a fantastic visual representation and explanation. Excellent work!
Dude. Ditto everyone else. This is a masterpiece. I've been trying to understand gravity intuitively for as long as I was start enough to try. Many other videos got close. Yours sealed the deal. Keep doing what you are doing. You're a genius.
A better explanation. kzhead.info/sun/Zq99g5uAjmd8a4E/bejne.html
@@danechegoyen3550 dude that explanation is ass
@@nathansykes9267 thanks for watching. What didn't work for you?
@@danechegoyen3550 I found it to be rather refreshing.. as a lay person, I cannot help but drift in thought towards a connection to the Gravitomagnetic London Moment.. do you have an explanation for that which fits into this model?
@@roberthelms1737 you really think general relativity is bs? give me your theory then genius.
Finally someone has created a visual that describes ‘spacetime’ curvature and movement that makes sense. 🙏
umm just the same as the rubber sheet. don't get fooled by fancy eye candy
right!?
Here's another one by Nick Lucid. . . kzhead.info/sun/eZmJls6rh5Z4rZ8/bejne.html
@@theoldhip Ooo Nooo, just do not direct us to that kiddy videos of the teacher for kids with ADHD.
@@shrike6259 its a step in the right direction
What a fantastic explanation! I had given up on ever understanding how this spacetime curvature was supposed to work, and here it is! Many thanks!
The last 40 seconds of this video was such a huge insight. We aren't moving through space, more that we are on a trajectory through time. And the trajectory through time is dictated by the curvature of the space time grid. We're seemingly always moving in a straight path, just that the geometry is curved.
The more you think about this it just keeps blows our minds
Not quite. Time dictates the curvature of space, not the other way around. I don't know why though vause it's a complete mindfuck.
Don't stop making animation like this, youtube education is more than everything... Well done!
@@mehmeteking well the title is only says how to "visualize" general relativity not what is general relativity
10:26 so a black hole is just collapsed matter that couldnt withstand the pressure of constantly accelerating upwards, and instead follows the natural movement of the grid
Exactly ;)
@@ScienceClicEN i thought I understood black holes.. but now I think I understand it even better
@@mortenfransrud7676 nobody _really_ understands black holes, because all our theories break down once you get to the singularity
@@n3onis Well that’s how universes are born
wow really smart thought. thank you
Using the longitude of a rotating sphere to explain how spacetime can be continuously contracting was very clever! That's the hardest part even for these animations because you have to repeatedly draw new gridlines out of nothing around 10:00 to visualize this with lines.
Yea. The actual curvature is,mathematically, the measure of the rate of deformation at a single instance. Extrapolating out in time is just a visualization aid.
I still don't get it 😢
This is by far the best no-nonsense clear-language depiction of how gravitation works in general relativity that I've seen on KZhead. Bravo for this excellent animation and clarification, and for putting the nail in the coffin for the trampoline analogy!
Great way to touch on Special Relativity too - "c" is not the speed of light, but instead is the "c"onversion factor between meters and seconds. One thing I always liked to demonstrate the 4-dimensionality of spacetime is a thought experiment: If you describe the motion of an apple with a 3-dimensional vector (up/down, left/right and forward/back), then when it's at relative rest, the direction of that vector is undefined. Stopping an object shouldn't break the math behind physics, nor should it leave us with a hidden direction variable - so something else has to be going on. Adding a fourth dimension means that when at rest in 3-space, the object is at maximum speed in the fourth dimension - time. Speeding up in one of the other 3 space dimensions necessarily means slowing down in the time direction, and you no longer need to use the magnitude of the vector to describe speed, it can be used for energy instead - plus the orthogonal space directions to the object's own time direction are no longer tied to the observer's space directions, so even time rate and dimensional length can change with the object's relative speed - therefore you get all the effects of Special Relativity for free.
Thank you. I have been thinking about it in this way for a while now. I like the way you put it
Yah
I am 18 now and I had the same idea as you and this video, exactly the same for 3 years now, I am amazed thoughts can be so common.
That is a good analogy, though it can be slightly misleading if we're not careful to remember (as best we can) to apply hyperbolic intuition to the time dimensionality of the analogy. Dr. Don Lincoln points out why in one of his videos on Fermilab's channel, "Why can't you go faster than light?": kzhead.info/sun/dJaDc9OBfqt9q5s/bejne.html
What a great little paragraph. Thanks.
2:54 “I f’n knew it!” - flat earthers
😆
Lmao
😂
hee hee
ROFL g1 !!
Absolutely brilliant! I always wondered in which direction the elastic fabric "bent" and just could not understand how that would work without a 4th spatial dimension. Your visualisation completely solved that! Thank you very much!
I've been waiting decades for satisfying visualisation of space-time that didn't rely on the "ball on a sheet" analogy, which never quite sat right. Thank you.
This video needs to be a part of the school curriculum.
@@fredericpool6754 Thank you for this! More people understanding physics = more possibility of advancing our civilization forward!
@@fredericpool6754 But the Newtonian explanation of "gravity" is much easier to understand for young students (and most adults!). Einstein's explanation is a real minder bender to get to grips with. It's funny to think he told the world about it 100 years ago, but only now people other than scientists have started to listen. Thanks mostly to amazing KZhead videos like this one, and maybe a few teachers who are willing to acknowledge limitations of the curriculum and give their students the opportunity to expand their minds that bit further. Good luck Frederic. Let us know how your students react!
chng.it/g5kZBmLN4Q Here you go, change.org petition. you're welcome.
Remember this video is not fact Just theory.
Remember, double check the meaning of words you are using...
The way you start out with a simple model and visualization, and then build on it bit-by-bit to make it more and more accurate and detailed is really elucidating.
kzhead.info/sun/Zq99g5uAjmd8a4E/bejne.html
Thank you for this. I've noticed videos pop on KZhead rehashing this. Did a little search, and as far as I can see, this was the first KZhead video with this visualisation. I am both in awe of the new gained understanding this has given me, and the talent behind this channel. Props!
Hands down the most accurate and informative video about general relativity on youtube
I love the little pauses that allowes what you're saying to set in
Me too! I really need those to comprehend everything.
Finally, the best visualisation of spacetime curvature due to mass-energy density on the Internet. I wish I had the benefit of seeing and understanding this when I was a student. Thank you! I have saved this video, and I will share it with my students should the need arise :)
not sure I still fully understand it. I might have to rewatch it. Kinda reminds me of fluid dynamics with a ball whose mass is being displaced underwater. If you were to pop the ball so to speak would gravity behave similarly to water in that it would rush back into itself or does it have a finite speed like light? My guess is gravity has no speed since spacetime itself is what is being altered not the distance within it.
@@geometricart7851 Gravity has been shown, by the results from gravitational wave detectors, to travel at the universal speed limit c.
@@geometricart7851 Spacetime and the metric tensor (distances between spacetime points of given coordinates) are the same thing.
“Should the need arise.” 🙏🏾Should be saying, thank YOU!
I want to spend also, but to see you get no "thank you" from the channel, changed my minds....
This is by far the best intuitive explanation of how the perceived "force of gravity" actually works! I've seen dozens of videos, and they all stop several steps short of a useful explanation -- but in this one, the beautiful visualization of movement through time makes all the difference, and IMO gets one as close as possible (realistically) to getting some semblance of an actual grasp of how "free-falling"/inertial objects behave in spacetime.
I keep coming back to this video as such an elegant and well structured way to describe relativity without a single math equation being required. Really world class. As an After Effects animator myself, you've done an amazing job leveraging 3D without being cluttered or distracting, that's extremely hard to do. Could you please tackle simultaneity and the twins paradox and shut down the all the competing explanations that never seem to quite nail it
i never liked that flat sheet representation. the three-dimensional representation is how i personally like to visualize space. but the frame-by-frame representation of time adds another necessary dimension
Exactly. I never understood the predominance of that stupid 2D visualisation. I'd always visualised it as a warped 3D grid in my head.
@@-SUM1- it's similar to the example of the black hole using a two-dimensional sheet coming to a pin-point at the bottom. that would be somewhat challenging to visualize in a three-dimensional manner while remaining round. it would take computer imagery to represent that the pull is taking place from all directions
That's the key Time (in some future) casts shadows on the past and is pulling everything forward. That's it!
@@AionAeon what implications does that have on freewill?
@@360.Tapestry within common sense & rules making this universe as it is; all the forces (eg of gravity, weak & strong nuclear forces and electromagnetism) we have the path that we (every '"I"') can choose or leave this choice to the Universe, Cosmos, God, Mother Nature, Coincidance, "just chemical reaction" - but it IS still our choice probably not 100% fate probably not 100% free will (thus is only for Compassionate Almighty Intelligence; probably out of this universe)
You know, I feel as though my understanding of relativity has been hampered by the "balls on a sheet" representation. I've been learning about relativity since I was basically a kid, and was eventually able to gather a decent understanding of the math behind it, but the warping of spacetime never made intuitive sense to be because through the entire process everyone was saying to imagine it like balls on a sheet (even legitimate academic textbooks). But finally after seeing this, I get what the math has been trying to tell me all this time. It's so simple and elegant. It's a travesty that relativity isn't taught this way.
This^ is absolute truth. This could've been explained earlier with videos. Had to think of the words to search myself
It makes sense to you because you know the math and are familiar with the concepts . I'm a nurse for 38 years. Temporal to me means the area of the temples on your head. I know he doesn't mean the medical definition of temporal, right? But how can I understand the without explaining to me what "temporal" means! How can I then understand the concept if he doesn't make certain I understand the definition of a word? THIS IS WHY EGGHEADS CANNOT BE GOOD TEACHERS. They can teach people with a preexisting knowledge of the subject, but not to someone like me. I so want to understand special relativity, but there is no one to explain it to a neophyte.
The representation of the balls on a sheet is a good one, the problen is that it's represented on a 2 dimentional "model". Use this representation but this time, apply it in all directions and you have what this video is discribing.
You are absolutely spot on!......about trying to visualize "balls on a sheet". And also about understanding how time can be 'bent'.
@@corgicottage8578 start with classical mechanics then learn that there are types and classes of subatomic (subatomic means any particle smaller than atom size) particles, next study the nuclear periodic table and isotope number, lastly and most importantly know that scientists revise the "standard model" of an accepted idea every ten years or so and standard models are there to describe to us the general public how something like general relativity or atomic structure works or looks at the cost of further intuitive knowledge or learning by giving us a simpler but sometimes inaccurate representation of a more complex set of factors 😉
500K ?! This channel is criminally underrated. This is bloody brilliant, thank you a lot for your content
I appreciate the occasional pauses to let us really soak in what we’re hearing and seeing. It helped as much as the information itself. Have a good day.
My man even pronounced the name "Einstein" correctly
Onestone
Eyenshtine
1:10
@@JoeOvercoat TYSM :)
As a german, I can approve.
That temporal part visualisation was fantastic. Never thought of it that way.
@@milyantsevmilyantsev3388 why do all russians assume the whole world speaks russian?
Someone told me that reality is quantized, it happens in frames, like in a film, 60 fps, and matter does the same but at quantum level and light speeds.
@@jakovteskera7521 Why do all Americans expect that everyone speaks English?
@@melodyparker3485 well its officialy the international language. Also, thr video is in english. Btw i dont even care what he said im just baffled by the idea of commenting in your native language, whats the point?
@@jakovteskera7521 Fair enough.
My dad used to explain things like this all the time, so I had always imagined a web much like you've described here. But I never considered the bend of space time in the way we're falling in a straight line. Now when people say "We're falling through space time" I can understand what they mean. Thank you, you've made my day.
This is THE BEST video on general relativity. I always come back.
When you are so used to english speakers saying "Einstein" the english way, that you are surpries hearing a good german pronounciation. Hats off to you
I've lived in New England all my life and this is the only pronunciation I've heard
@@luminescentlion that’s because it’s the Yiddish pronunciation
m.kzhead.info/sun/isWmdppsfniGrZ8/bejne.html
Schoonds like Tony Soprano talking
@@roberthelms1737 how so?
Einstein watches this and starts yelling: “Finally, finally!!!!...”
I’m imagining sponge bob
Idiots he understands it better than any mortal that existed ...
@@thewolverine7516 called a joke relax
@Davgil Lol
@@thewolverine7516 its a joke you crackhead
Kudos to you!! This is the first video that correctly explains and visualizes space-time curvature and its manifestation as gravity! I am a theoretical physician and with good conscience I can tell anybody who watches this video: This explanation is 100% correct and Alessandro Roussel found a clever way of visualization. This video should be part of any lecture about General Relativity.
This had to be one of the best explanations on relativity so far! Beautiful!
The animations are superb! This is definitive proof that well-made visualizations are really good at facilitating the transfer of knowledge. Congrats!
This is how I imagined it. That 2d model always felt incomplete because celestial bodies aren't sitting on a sheet of spacetime.
Yeah, but the Sheet-analogy is more accurate. It is a single 2D slice through space, showing the time-distortion as a distortion into the 3D dimension and doing so without the need for an animation even.
Yeah I know there's something wrong with the sheet of spacetime. But aren't the planets in our solar system orbit the sun on a fairly flat plane? What do you think of that?
yeah, I was always confused why they would explain gravity by gravity to the point where I was sure that either the representation is wrong or general relativity is wrong. While this video made me realize that the representation is not actually what general relativity says, I still think general relativity is very wrong and far from reality.
@@mnguyen4684 the planets formed from the same gas cloud. So, unless some external force acted upon one of them, it makes perfect sense that they all belong to the same plane.
@@yasseindahshan3556 why? because it's not intuitive? the universe is under no obligation to make sense to you as NDT said. Our brains and senses are adapted to the natural world we evolved in and that's it. Denying something because it just seems wrong is just ignorant. Same case with quantum mechanics. the interactions on the micro scale seem so bizarre to us. But, if we were atom-sized they would be the norm. Quantum mechanics would be called 'classical mechanics'. I hope you get my point. I urge you to dive into the mathand logic behind science before ruling it out as an improbable solution just because it seems odd.
I ve seen many illustrations but this one is by far belief shattering. Thank you!
Wonderful graphics and beautifully explained. Thanks!
117 dislikes are by flat space-timers
Poor folks who can't afford to travel outside their own localized Euclidean patch...
By far the best comment
wow
Or people that notice that this animation is rather horribly complicated for how little information it conveys - less than the simple sheet analogy even.
@@ABaumstumpf Dude it’s just a video representation that takes advantage of the properties of video. With a step by step explanation of the differences. Why so mad?
"the apple is travelling through time, but the curved spacetime is bending towards the earth and..." HOLY SHİT! mind f'n blowing!
Yeah, it really hits differently once you realize it's not just space (or travelling through it) that makes the apple fall but also time. Gives a sense of inevitability. It's not just a matter of space but also a matter of time.
@@tdcfc It is a matter of perception really. If you study Einstein's field equations, Space-Time is a single continuum. A single function but because the arrow of time or the effect of time is the same for all of us, objects with no spatial velocity appear motionless. All of us might study the mathematical significance of an equation but to intuitively grasp what it actually means is another thing entirely. Nonetheless, this is perhaps the best explanation of relativity that I have come across on KZhead.
@@tdcfc it's literally inevitable here because in GR spacetime is one quantity, the future and past predetermined as a block universe
@@tdcfc now you know why beings that can tap into the 5th dimension are soo overpowered
@@tdcfc it gets difficult following the old 2D graphics. Time is a result, of matter in motion, time is an illusion. Matter "happens" and moves, thus, creating the illusion of time I think I saw two more channel that covers this, the science asylum, and Pbs spacetime.
11:02 is the intuitive visualisation I have searched for, for like a decade. Thank you
This is one of the best videos in the entire platform.
When I was little, I always had the problem that gravity was explained with gravity. This video showed me that I never was alone.
Exactly! And I was so confused that no one talked about this serious flaw in that model.
Same here .
Whenever I heard that explanation I always asked that question Why is it falling down ...which force is pulling it down !!
@@Pikachu-vo7qb I imagine the teachers telling you might have had trouble explaining lol
@Muckin 4on Ah but nothing is actually contracting - It’s the geometry of time that is being affected by a massive body. If you sat on a chair for 3 days and didn’t move, you are actually still moving through time in a given direction, it’s just that we don’t perceive this as a motion. If I then stick a massive body by you, the direction of this motion will curve towards it as the direction of this time’s journey has been influenced by a change in the geometry of the space in which it’s travelling. The model showing perpetual contraction is just a way of showing how every object is making a journey through time in a given direction.
The best graphical explanation of relativity I've seen. Simple and intuitive.
Man, this is the single coolest explanation (plus visualisation) of GR! Congrats and keep up the great work!
I watched dozens of videos trying to understand these concepts, and so far, this is the best one. How is it that the balance between the gravitational field and centripetal force has been maintained for billions of years, preventing any derailment?
Some ideas for further renders: 0. Expanding universe. 1. Planar gravitational wave. 2. Rotating black hole. 3. Merger of two neutron stars. 4. Krasnikov tube.
@@vzlfkr The speed of light in a vacuum is the same for all observers, regardless of the motion of the light source or observer. You can never catch up with the speed of light. Even if you manage to travel at the speed of light, light will still travel at the speed of light relative to your observation. Time will move differently for you, compared to outside observers.
@@vzlfkr I think you should watch this: kzhead.info/sun/lNlpga6RgIWbZ5s/bejne.html
@@vzlfkr You should watch the video "Will we ever visit other stars" by VSauce. In the last few seconds of that video, they have shown the animation for the situation that you are describing.
@@Jaredvotesforpedro you are absolutely wrong. Light is moving slow than time. Even light is to much slow than your imagination.
@@ujjwalbhattarai8670 lmao wtf are you even trying to say
I can't say thank you enough for making this video. For decades I have struggled to try to visualize a way to reconcile gravity, time, and space and you have helped me make a breakthrough. I'm so grateful for your intellect and willingness to teach and share!
Don't get too excited. This video is as flawed as all the others. It is well made, but the reason it seems so much 'clearer and easier to understand' is that it is pretty wrong, and quite inaccurate in many ways and simply appeals to those craving s better visual understanding.
@@timothyfountain3399 But what of Sharon Jones & the Dap Kings?? _Please refrain from replying to this Comment._
@@keepcalmycarryon I'm sorry but your comment makes no sense.
@@timothyfountain3399 That is because you refused to abide by my clear instructions. Must the hoi polloi be so obstinate?? _Le Sigh._ Related, my gender-fluid & hetero-flexible friend "Chocolate" is seeking an ironic arranged marriage to a KZhead Commenter immediately, & your choice of patronym would suit him & myself well with the subsequent risible name combination. What say you? Need I spell it out for you? Also, what is your shoe size? _Good Day & God Save the Queen._
Awesome isnt it?. And good to see trip 7s floating around! Best number 😉
I've never really understood this principle. It is beyond my grasp, however, all other explanations I've seen weren't nearly as clear as yours. Although I still don't comprehend it, I believe I've understood more of it thanks to youj.
Thank you so much for this video! Every time I saw those typical visualizations and demonstrations that you show in the beginning of the video, it always made me wonder why the moon doesn't crash into the earth, why the earth doesn't crash into the sun, and so forth. Now I FINALLY understand that the earth doesn't actually orbit the sun, the earth is just travelling on a straight trajectory and because of conservation of momentum, no forces acting on the earth, and spacetime being distorted by the mass of the sun, it just APPEARS as if the earth is orbiting the sun. The earth is just travelling in a straight line; wow, I can't express how profound it feels to me to FINALLY understand this!
The more i think about this it just keeps me up at night just insane
I like how you pronounced Einstein the German way.
Something I was about to comment upon!
it's furstrating when i mention Einstein in the UK and people try to correct me when i use the true pronunciation...... people just wanna butcher names and call you incorrect XD
first time in the internet i heared his name pronounced right
@@Aurimas97 Same! They look at me weird and never believe me.
@@agrimarora1522 Sorry I did it before you. There's probably someone who did it before me though
I struggled with this for a long time, and eventually wound up with more or less this same model in my head. I just wish this video had existed back then to save me all that trouble. I'll probably refer people here for whenever I'm trying to convey how GR works to someone.
Glad you liked the approach !
same
bro exaxtlty
same here
@@ScienceClicEN ur channel is amazing and so much clear info in so little time
This is incredible. Thank you! I've always hated the rubber sheet model for exactly these reasons, and this makes so much more sense to me. One thing I still don't understand, though: the spacetime is curved by the presence of mass, but the path of the mass is determined by the curvature of the spacetime. How can that be? They seem to be defined circularly. Is it accurate to think of each time-slice of spacetime as being "generated" by the world state within the time-slice before it (which is how we generally think of cause and effect from within our human perspective), or is there some way to understand the whole spacetime without generating "frames" one at a time? Or am I asking a question without a meaningful distinction?
I remember when youtube started and people were doing the first 3d grid animations, because the elastic fabric example used in tv was obviously limited. Many of us kinda visualized this because it wasn't so developed yet. It's amazing to see it done so beautifully, felt like waiting 20 years has finally resulted in a chapter of my life coming to a conclusion.
I have not felt this way since childhood but you genuinely blew my mind at 7:18 with that intuitive explanation
exact feeling im having right now
if you liked this concept watch their video called "why time and space swap in a black hole". it's even more eye opening since not many people know how space-time works inside a black hole
If u want get more mind blown search KcIndustry or Jeranism
@@RafaelMunizYT Thank you for this reco, and the other person as well Anything on White Holes that you've seen that's worth the time? TIA.
Any physicists here want to tell me if an idea I have is right? Not sure if there are any here.
7:37 "The curvature of spacetime, generated by the Earth, has merely converted its temporal speed into a spatial speed."
But speed always involves both space and time: speed = distance/time. So it doesn't make sense to say "temporal speed" or "spatial speed". Speed (or movement) is always both temporal and spatial.
In relativity you can also define a distance in time (time is a dimension just like the 3 dimensions of space). The "speed" is calculated with respect to the proper time of the object, while the "distance in time" is calculated with the time of the observer (it's a coordinate)
@@ScienceClicEN Are you saying that in the statement about converting "temporal speed into a spatial speed", the two speeds relate to different times: proper time and coordinate time?
Both speeds are measured with respect to proper time. Spatial speed is the change in the spatial coordinate as proper time goes by, and temporal speed is the change in the time coordinate (the time measured by the observer) as proper time goes by
@@ScienceClicEN OK, clearer; thanks.
Thank you so much for making this video. I’ve always been so frustrated by the traditional sheet model that is usually utilized. This is brilliant. Keep up the good work!
An excellent and long-awaited visualization. Thank you very much.
I’ve literally always imagined that space time looks like a warped 3D grid in motion but I’ve never seen someone so accurately depict it thank you!!
Ditto. Got told I was mistaken for visualizing it this way. Glad to know I wasn't cracked lol
same :D this video was awsome!
@@bklanyon176 visualising it the right way, you might still be wrong about reality
Same
*"I’ve literally always imagined that space time looks like a warped 3D grid in motion but I’ve never seen someone so accurately depict it thank you!!I’ve literally always imagined that space time looks like a warped 3D grid in motion but I’ve never seen someone so accurately depict it thank you!!"* Yet he has it backwards.
Students need to see this when learning about gravity. Incredible how it makes so much sense with this context
You understand this? Kudos to your superior IQ
@@amir_hamzah it's really not that difficult. You just have to recognize that it is impossible to truly visualize, and instead process what it is trying to represent as your own visualization within your mind.
@@nathanb011 it is very difficult as this explanation is in fact an hypothesis. It is not that it is impossible to truly visualize general relativity, it is impossible to determine what the fabric of the universe really is in the first place. Dark matter is a possibility, but it has not been observed. In other words, it is really difficult if you are really looking for an answer.
@@andradas9688 dark matter has been observed in the sense that we know for certain it is there, we just don't know what it is.
@@nathanb011 well, yes, i did simplify my comment using the concept of dark matter. I didn't want to mention dark energy, for instance. The point was just to have an alternative take on the idea of "it is really not that difficult". I was not attacking your comment, btw. It is just that complexity is inherently difficult.
i dont know if anyone beleives it or not.. but while in my school i imagined it exactly like this in my mind.. i thought it was normal anybody can imagine it this way.. i tried explaining it to my friend at school but i couldnt he didnt understand.. and after a few months here i am looking at this video.. im so proud of myself... considering the fact that i want to be a theoretical physicist.. this is giving me so much motivation to move forward in my aim that i can do it
That’s impressive
Finally I could understand the concept and definition of the gravity with this simple and illustrative animation! I've watched too many videos in KZhead, but this one explained the gravity and bending the space-time directly without using gravity to define the gravity like the other videos do! Thank you very much.
This deserves an infinitely large number of likes !🔥
Thanks 🙏
@@ScienceClicEN I have never seen or heard something as complex and counter-intuitive explained so clearly! Thank you from a science geek in Minnesota who can now tick off one more box on my "what to do during the pandemic" list!
and zero dislikes
But how would you define infinity
@@Aman-br1ph infinity is a really large number whose value cannot be estimated So if the no.of likes goes on increasing without a particular value at a particular instant It's like a simple exaggeration of the value that every single person who has an account in youtube shall like it ,then no.of likes is infinite as it will never stop increasing
I restored braincells after trying to understand politics
I can tell you precisely: Socialism is when things are ruled in the interest of the people. Capitalism is when things are competed over and denied, excluded from the people. For Karl Marx, these things are narrowly economical, but he researched it a long time ago. For our leaders and media, Socialism is the stereotype of Soviet model, which was corrupted by Capitalist leaders and laws, although it began with the interest of the people in mind. Stalin was a Capitalist not in the sense of Free Market and Central Planning but by socio-political outlook. Authoritarianism, Dictatorship, Totalitarianism are mistaken as Socialism and Communism is mistaken as the outcome of lack of Democracy. Democracy is mistaken as the flawed election system, where power and decisions are not discussed by people in person, but by Capitalist leaders and laws. Capitalism is mistaken as Free market, freedom and Democracy, because it is depicted against the context of Totalitarianism, Central planning and not American economy, which used to be expansive at the time. Therefore Central Planning and Free Market is just a practical question and has nothing to do with Left or Right. In the end, the Anglo-Saxon Capitalism was the narrative of only the rich. Capitalism is every way of anti-social behavior, because it excludes the Other, even if it gives Freedom and wealth, and even the fair Soviet welfare. Democracy really should have everybody in the discussion. Socialism doesn´t really exist in the welfare programs of center-left parties as it was Marx´s word for the worker´s control of the means of the production and it must be rewritten to mean the Ideology of moving away from all Capitalist leaders and laws. Communism was Marx´s possible outcome for having the means of production in the hands of the industrial workers. The poltiical left is defined as "Equality in expense of Freedom or Security" and political right is defined as "Freedom of Security in expense of Equality". That is why Socialism really is only Libertarian Left,, not Authoritarian, and Capitalism is Authoritarian Right, because it cares about Freedom to enterprise or from other people´s competing influences. Neoliberalism is Libertarian Right, which fantasizes about the ultimate Free Market as the source of Equality, Freedom and Security. Right can never ever actually be free or secure without Socialism. Therefore Equality and Libertarianism precede the Right Ideologies and are prerequisites of Freedom and Security.
@@teemum.9023 k
@@teemum.9023 Politics is not a list of ideologies filled with good wishes. It's also about why those wishes never fulfill and what practical means have been proposed to achieve them, and why those have failed or succeeded, and so forth and so on. When you see politics through that lens, they become a headache that rivals Relativity.
@@somedragontoslay2579 But I said I can tell it specificly. The system of ideologies is as clear as this new visualization. Yes, politics is also about working and balancing in a diplomatic setting. With Capitalists, everyone tries to get their own interest and it becomes corrupt and fake, pretentious populism. Honesty is very restricted, and even Obama was limited success. Even if all the leader were altruistic, the people are not there in person, don´t know what is at question and don´t hear any of it = Capitalism. Pierre Bourdieu wrote the types of capital, social, economic and symbolic capital (culture, politics, narrative). All these can be used in a Capitalist way and in a Socialist way.
@@teemum.9023 socialism isnt bad in and of itself, but the thing is, it is nigh impossible to pull off with humand being as they are. you are mistaking the natural unlikable side of human nature with the effects of capitalism. socialism is a nice ideal but it will never work unless humanity as a whole goes through a reform.
The explanation is phenomenal 👏 A satisfied approach for basic understanding and which will not distort things when learnt in detail
This is by far the best representation of space time that I have ever seen. Thank you!
🙏
Finally, after a million videos on GR, i finally understand it. The creator of this video deserves an award
This is so mind blowing. Never seen a more better explanation.
u should look up a more better adjective for more better
@@guccihorsepiss2406 You should use the word you, not u.
@Gucci Horsepiss u should look up a more better spelling for u
kzhead.info/sun/i8dtqL2ZmoarYH0/bejne.html
@@CountofSerenno in informal communication and that too social media use of pronouns can be different and can be anything but it can be used until the person can undersatnd what u r saying so here I used u , r means you are and you took it same way so it doesn't matter but the word more better matters as he can use best Don't talk much if u don't know what can be used at respective places
Of thousands of videos and text books made, this is the greatest in explaining gravity phenomena, simple complex understandable and in a short time, you guys deserve an award in vísual science & education if such existed.
This is by far far the best video i have seen which describes general relativity.
Physicist explaining theories Apples:- Dont forget us
Apples are the most influential fruit of all time.
On the German Language KZhead channel Urknall Weltall und das Leben they do everything with oranges. I guess they're Leibnizians.
best meme ever.😂
Physicists use apples because they hate doctors.
Steve Jobs: Stonks
Einstein would have cryed had he seen this explanation through this animation. Thank you!!!
I think Einstein would have dyed. Perhaps he'd be green with envy.
Well, back then it was probably your best bet to only target people with good understanding of non-euclidean geometry and give them mostly formal definitions. Even now, without formalisms you can easily get lost in reasoning, but thankfully we can also get nice intuitions from others (through visualizations like this one).
I’m pretty sure he would have looked at it and said “Of course! Exactly”
I crie when I see spelling like your'es
That's a beautiful thought! How pleased he would be to see this.
OMG thank you! I am a 12th grader and I have always had a particular interest in space and astrophysics since third grade. I always kept wondering where the 4th dimension (time) would get placed on the 3D graph lol. After watching this video I think I understand the space time curvature much better than before. I personally think it's the most appealing way to describe the theory of relativity and the space time fabric in an animated video.
bro this cleared my every doubt or confusion regarding relativity ever existed. You have my respect
The short version: you blew my mind The long version: When time was invoked and the temporal speed was being explained with the sliced views, I legitimately felt a pang inside my head. Like a phantom adrenaline rush solely from brain activity. This felt like receiving eldritch knowledge (the kind that would supernaturally drive humans mad if not kill outright) at 1/10,000 the potency. I felt a rush of understanding for a few seconds but then lost it trying to process it. Like a car failing to start but still making the noise of attempt.
Bro, same! At the same part of the video, same rush of joy was building up inside me, then I lost it
I like the way you expressed it in words. “Eldritch knowledge”, haha, I love that! I feel tingles and my hairs stand up on end, goose bumps, and I too get a rush of adrenaline as a feeling of epiphany flows through me. For me it’s like getting a glimpse into the ancient Hindu god Brahma, and his fabric of reality called Brahman. I truly believe physics and cosmology are “religion done right”. The questions are the same, “what are we? Where do we come from? How was all this made?” But instead of snake oil we have a rigorous scientific method and falsifiable hypotheses. No dogma, no blind faith. I think religion was just astronomy and cosmology at one point in the past, but somehow veered into snake oil and dogma from that. With the right visualization tools we are peering into the objective reality that underpins our existence. It’s a type of communion with the ultimate.
Yea. One might getting a little obsessed with it. When i was pondering about how our reality could be simulated i had a "relative" idea. Spacetime as simple 3d energy grid, not curving or bending around matter or inwards, but is absorbed by matter. Matter itself determines how much spacetime, whereas the concentration of spacetime determines the "curvature", gravity. Like clay clumping within fine 3D netting, deforming it.
@@palasta bro check the math for that you might be unto something
@@mclilzenthepoet2331 If i had a much better understanding, sure. But i don't. Besides it might sound like a neat idea, but human intuition usually isn't helpful with these things. It prbly violates whatever laws...
Really great video. The sheet analogy never properly "clicked" with me, and this explanation helped me understand why.
This might be my new favorite channel.
Props for pronouncing "Einstein" correctly. Sincerely, a German
Just thought the same :D
Just said the same thing
@@radoslawszymula6560 small brain time
@@radoslawszymula6560 What? You mean WW2?
@@radoslawszymula6560 Uhhh, he's from Germany, so you say his name with a German accent... You good?
This was the best video on GR ever seen. Was searching for this kinda video since I've got to know about GR. Thanks alot. The makers deserve alot of respect. ❤️. Thanks again. Keep going. This channel is a must follow science channel. ❤️ Please upload more English versions of your videos. Love and Respect from India. 🔥👍🙏
@@stridedeck Talk about misleading. What I object most to is the "better" claim. It's not better, because it is not about GR so can't be compared. It's a 5 minute infomercial about a theory called One Source Universe.
@@stridedeck uh oh, you's suuuuuuuuuuuch a moron!
to that I say kzhead.info/sun/dNOwpKt8hGuklI0/bejne.html
Thanos - Mogambo🤣🤣
This looks fantastic... I love when science and motion graphics come together... Its the only way everyone understands things and get on the same page
Elegant and beautiful description .
Einstein: damn it! This is what I was trying to explain 80 years ago.
How is space expanding visualized given this visualization?
@@abdulqadirahmedli610 I was born in a muslim family, but now an atheist and hate people who push religion and God into everything
@@spec_wasted Why hate? To some, God is everything. The Alpha and the Omega. The beginning until the end. In that sense, another name for God could easily be 'The Universe'. And when one of such belief tries to understand the universe, are they not also trying to understand God? All that exists? That is, unless one believes that God is a creepy old man, sitting on a throne ready to dole out punishment on the imperfect children he (she?) created. I dunno. To me, the concept of 'hate' just reeks of the Dark Side of 'The Force'...
@@bullpuppy7455 Religion and God is used to run societies and build common places for a particular religion where people can attend and learn to hate other religions
@@spec_wasted One might say the same about 'borders', 'countries', 'states', 'flags', and the like. Either we are children of the Universe (or of God - whatever you want to call it), which makes us each brothers and sisters, or we are not...
I have been trying to wrap my head around gravity not being a force for a while now and you’re Video is what finally brought me some clarification.
Says a woman 😑
@@lawliet2263 what?
@@dish7877 women don't have brains and then there's this woman trynna wrap her head around physics stuff lol
what an impeccable visualization!! truly mind boggling phenomenon demonstrated with a beautiful combination of animation and music 👍
Literally most intuitive way of explaining it. I knew the conventional analogy was is some way flawed and the creators of this video found what was wrong with the analogy. Thank you so much!
The only single improvement I can imagine is to create a 3D side-by-side video version I can watch with a VR headset. No idea how to create one though! This is an excellent video. Thank you.
Would be really cool ! I am going to try that ahah
Sounds like something fairly easy to throw together in Unity.
This is hands down the best explanation of gravity and everyone should see this!! All of the previous models never made sense and cause me to have more questions than to actually understand how any of this worked.. Now I do and I do clearly. this should replace all other animations or representations shown today. Thank you for finally making this model. I cannot believe we ever tried the marbles on a sheet example now that I see this.. How in the world did it take so long for anyone to make this version. This is crystal clear and perfectly explains gravity and answers all questions and doubt created by previous illustrations. Thank you for this!!
Fantastic vid, the animation, narration, writing, it's all just top notch!
It's so rare when something genuinely new comes along in the relativity / visualization area. I'm 3 years late (depending on your relative velocity :) but today was exactly such a day! Fantastic video, superbly done.