Tu fais un travail de dingue mec,tu traduis tes vidéos en anglais en plus de les faire en français;en plus de ça le montage et ouf et c'est du contenu de qualité.Franchement tu mérites beaucoup plus d'abonnés. You do a crazy job dude, you translate your videos in English in addition to making them in French, in addition to that editing and phew and it's quality content.Francely you deserve many more subscribers.
You can’t “explain” gravity by the concept of Newtonian “gravity”, your bowl model is only valid due to newtonian explanation of forces and gravity, it would became better if you explained it as objects meets because they are traveling along a curved path which is space-time, so as time flies objects move along that curve and meet eventually
Yes you're totally right, this video is an introduction to Einstein's point of view and I think the images of the "bowl" or the "rubber sheet" are useful as a first introduction. They help understand that objects attract each other because of the geometry of an underlying object (spacetime) on which they are placed. But if you want more thorough visualizations check out my other videos on General Relativity I have made multiple ones in different levels (this one is for beginners)
@@ProgressiveEconomicsSupporter Just as likely as all of the other objects that failed to maintain an orbit and crashed into the larger objects. There's a reason why the moon is peppered with meteor craters!
@@dsaun777 Destroy all potential of any photons as well. As the last signature of humanity, we should destroy all! If we don't have potential, neither should they!
Einstein's theory of general relativity gives gravity the tag of an illusion rather than a force, which I think is better than the newtonian gravity. But I think we should not forget that newton created his own mathematics in order to prove his theory for universal gravitational force!!😅 Which is truly epic and induces a greater respect to me towards him.
This is a wrong description as it explains gravity with gravity. In the video it is Earth's gravity that forces B to go to the bottom of the bowl. Actually, it is curvature of time that explains why relatively small masses like Earth create attraction. Time goes slower near Earth. There are good videos about this on UA-cam.
Yes, actually I made a video precisely on this : ua-cam.com/video/wrwgIjBUYVc/v-deo.html However I still think this fabric analogy is good to begin with, as it makes it easy to understand that objects attract each other indirectly, thanks to an underlying container (spacetime), which can be bent and curved by matter.
@@ScienceClicEN That model can perhaps give some idea what is happening (curvature). But the problem is that it does not explain gravity at all! When I first saw this analogy for a long time ago - before internet and UA-cam - I was immediately wondering what makes B actually move to the bowl where the big object A is sitting. That was never explained. I have seen correct explanations only during last few months (I have not tried to search explanations).
In the analogy the thing that replaces gravity is time itself. In a spacetime diagram objects must be moving. This is the real reason why an object follows a curved trajectory.
If 2 objects are stationary in relative to each other, they are still moving, thru time. The object's eventually collide because gravity distorts time and that distortion of time bends each towards each other until the converge. That's my current understanding, where do I go from here?
This video is amazing, thank you so much! I have one question after all: How does this model explain gravitational forces like the moon having an effect on water on Earth?
Question! The space time is 3D. Now the 3D space time grid is distorted in all directions around "A". In which plane would the object "B" orbit and why? Also, this representation suggests that the "B" is attracted and will be colliding with the bottom part of object "A" and not the center of "A".
Spacetime is 4D, not 3D. As you say, it's distorted by mass. The distortion takes place entirely within the four dimensions of spacetime. No higher dimensions are physically required. In mathematics this is called a "manifold." en.wikipedia.org/wiki/Manifold
A class mate recommended a video in our physics class about the quantum field theorie and although the subject was imo a bit to advanced for us, i really fell i love with this channel and it's "simler" videos. Great job. Another thing, what's the music track called playing at 0:38? It's really relaxing and unnerving at the same time and i really want to listen to it.
You are using gravity to explain gravity. They object falls because of gravity not because of the curvature of the bowl. Put the bowl in orbit and the ball will float away.
The elastic sheet is a good first approach to understand that objects attract each other indirectly, through an underlying fabric whose geometry they alter. But yes you're right this model is not very satisfactory as it sort of describes gravity by gravity. Check out my other videos for better visualizations ;)
@@ScienceClicEN I have seen your other video. You are the best channel I have seen so far and I have been been studying physics for over 50 years. I saw the rubber sheet analogy years ago and it upset and confused me. I tried to explain my objections for years and everyone laughed at me. Your video is a good first step but for me the rubber sheet caused a great deal of suffering.
@@jacobshirley3457 I like the rubber sheet idea. I saw it in a book by Edward Harrison 40 years ago. It is just that some internet physicists used to make fun of the idea. Most of them aren't very good at being physicists. Like I said before this channel is by far the best that I have seen on youtube.
This is a great illustration of the difference in science between a LAW and a THEORY. Newton's laws of motion, like all scientific laws, are purely descriptive. They only say THAT something happens under certain conditions. Einstein's special and general theories are accounts of mechanism. They make the case of HOW something happens. And because we can say HOW something happens rather than merely THAT it happens, we can predict what else SHOULD happen according to the theory.
Wrong. Newton's Law of Motion explains literally everything that involves motion. Einstein’s baseless theories only explain 'gravity' which doesn't even exist. See the Higgs Boson. See the hammer and feather drop experiments. Newton's Law of Motion perfectly explains the hammer and feather drop test. Explains why clocks in motion are slower. Provides a solution to the twin paradox. Einstein muddled it all up with his relativity theories and now you are lost and confused. Having to resort to such machinations as warped space and time (fudging the numbers) in order to get relativity to fit reality. As Nicholas Tesla said. Relativity is a bunch of mathematical nonsense that has hidden the underlying errors and confused people. Look how confused you are when you don't even understand 'gravity'.
It doesn't explain why though. Distorting the grid could equally well cause objects to be repelled, or go pretty much anyway except a straight line. Was expecting a better answer
He would have gotten into the math. Earth and the moon has a speed thru space. If the moon has the right speed for its mass it will constantly miss earth at an even rate, we call this orbiting. The international space station does this by achieving 17,000mph at a certain altitude, always falling, but missing earth in space-time. ➿〰️🔄
@@alexgmihai242 _"There is another video on the channel that explains this better"_ Yes but even that video just says Earth is sucking in spacetime like a vacuum cleaner without saying WHY it is sucking spacetime like a vacuum cleaner. It is unknown to humanity why it does this. No human knows why we fall. The title of the video "Why do we fall?" is clickbait. The question is not answered & nor can it be without new physics
The Galilian transformation most then also work in the Electric/Magnetic wave, meaning that the centre and the wave horizontal or verticaly will end up at the same time, in the centre. There is no time differance, it just looks like that. It matters not if you move diagonaly away or in a parabool, you will alway's see your mirror equation in the Galilian transformation. 😮
One doubt.... A marble in a bowl falls... Or the way that moves inside the bowl is because of the gravity... Acting on the marble downward.... In gravity free space this will not happen.. then how we can say that the space time acts like the marble in the bowl... In our current scenario...???
Your description of B moving towards A is using gravity to describe gravity. This is why the rubber sheet analogy is so wrong. If gravity was simply the curving of space then nothing would fall, it would simply stick wherever you put it. The explanation of gravity must include an explanation of time to make sense, because its spacetime that warps, not just space. Time slows down the closer to A you get, so there is a time gradient across any object in a gravitational field. e.g the part of B that is further away from A is moving through time faster than the part of B that is closer to A. The real question tho is why (and how) a mass warps spacetime at all.
@@FOXTROTALPHA2412 The way he explains it in the video suggests some sort of directional force is acting upon the falling objects through a 4th dimension, pulling them towards the "bottom of the bowl". This is inaccurate. The whole point of Einstein's version of gravity was to show that objects in freefall aren't actually accelerating, but are stationary on a grid that is compressing.
Aren't you trying to explain gravity by gravity itself? Space-time is a 3D grid + 4th dimension (t), then you're explaining apple falling story with earth/sun example on 2D like stretched space-time fabric ?
From the constructs presented here I can’t see any particular advance beyond Newton’s conceptions or anything else’s besides given for the ‘cause’ of gravity as you put it. I don’t know if I have it right but I am not sure that Newton gave a cause for gravity or ever could since he regarded it as a ‘general effect’ - although the operation of this effect was quantifiable and this he provided with his inverse square formulation for it - boiling down to doubling the attraction for each halving of the mutual distance of centres. Since the effect is so much greater at the surface than any distance away and dissipating with distance at the same rate as that for attraction - personally have never seen what is meant by ‘space-time’ and the depressed trampoline surface image provided to explain it. You place two snooker balls ever closer together and at the finest approximation a magnetic effect takes place and they ‘click’ together - but what’s that to the larger spaces of any sized table on which play takes place? I’d like to know what is mistaken in this view.
the bowl analogy is not very satisfying.. just because it implicitely uses GRAVITY as the force to make the marble roll down.. you cant explain gravity by using gravity
Einstein was looking for little children to sell a story to and he found the physics community. An objects 3 dimensions change with time but space and time are different things defined by humans. Gravity is just a phenomenon caused by the ejecta of the universe in the form of profuse superluminal fundamental particle of extremely low mass that comprises the mass of elementary particles forcing objects against other objects that shield each other from the contralateral universal hemisphere ejecta. There is only one force in the universe, the strong repulsive nuclear force which itself is a consequence of the kinetic energy of the fundamental particles emanating and entering the core of all long lived elementary particles and bosons.
Why do we fall? We don't, we are standing still, there is no reason for us to move. What did you think? That gravity was a spooky force acting at the distance? The Earth however has a reason to move, its atoms are pushed apart. The Earth expands. And I guess it will always catch up to you. Why doesn't the Earth seem to grow bigger? Well it is constantly getting scaled down because of a bend in spacetime.
If it's constantly getting scaled down then it will never catch up to you. You're trying to have your cake & eat it at the same time. You're trying to say "the floor moves up but it doesn't move up". The floor is moving through time at the speed of light c. It got this movement probably at the Big Bang or thereabouts. When we start to fall, there is a relative movement between us & the floor. The space between us contracts until we connect with the floor. You can say we're stationary & the floor moves up. That's fine. & you can also say we're moving & the floor moves down. That's also fine. But both are mere labelling similar to saying "people in Australia are upside down". What's reallly happening i.e. the invariant thing is that the spacetime between us gets smaller. It gets smaller because the Earth's mass sucks the spacetime like a vacuum cleaner. No human knows why this happens. Therefore no human knows why we fall. However physicists do know 1) the spacetime contracts & 2) both the floor & us are moving through time at the speed of light. We are moving along a straight line into the future. As the spacetime contracts this straight line curves around. This means that instead of moving towards the future we start to change direction. We follow a curve. This is like how a car travelling north will start curving west IF the road is curved. However humans are blind in that we can't see the time dimension. Therefore it seems like we fall in a straight line until we connect with the floor. It's like we can't see north-south so we just see the car stationary & then we see it move westwards a little bit, then it accelerates westwards. But the car isn't moving just west like that. It is following a curve. Sorry to explain unclearly without diagrams & animations
@@alwaysdisputin9930Does that mean that when an apple falls, the apple is actually still, but the floor is accelerating up to meet the apple AND at the same time the apple moves in a curved time, so in a curved line pointing at the center of the earth?
Thank you so much for making a sister channel en español. Quiero conocer sciencia en inglés y español porque tengo amigos que no hablan inglés. Estoy aprendiendo español pero necesito vocabulario y gramática. :)
The curvature of the space-time is distorted, so that the physical geometry tends towards objects with high mass. The usual analogy is misleading I agree, it's difficult to represent the 3d geometric distortions visually. Insidd the event horizon of a black hole, the geometry is so distorted that all directions lead into the center of the black hole.
What if objects with mass lagged behind in time so if you look at a space-time diagram it would look delayed and further back in time, that would explain time dilation as it warps the fabric and also gravity since it bends the time axes of other masses towards it and vice versa
Just like we know the amount of force due to a specific mass in Newton's theory: with an equation relating both concepts. For Newton's gravity you have the Law of Gravity: F = G Mm/r^2 (in module) For Einstein's General Relativity you have an analogous equation, though a much more mathematically-complicated one: Einstein's Field Equations, which instead of using vectors to represent forces it uses tensors, kind of a generalisation of vectors. Just like Newton's law tells you how much force there is given the masses and the distance between them, Einstein's Field Equations tell you how and how much the space-time curves given a certain distribution of energy.
Albert Einstein is probably the most fascinating person to me. I understand the explanation however, this explanation doesn't explain everything. Many questions can challenge this theory.
How do we know mass causes warped space (gravity)? My postulate is that warped space (gravity) causes mass, fermions. And we now know that gravity waves travel across space.
Gravity waves propagate IN spacetime, not through it. While this distortion and mass are so closely related that it might be hard to say which is the cause and which is the effect, we can use some additional clues to help us decide. Fermions have properties in addition to mass. Spacetime doesn't account for these properties, and moreover they are highly localized to each fermion and invariant with each instance of a fermion. Conversely, spacetime has no known properties of itself, other than the geodesics of GR. So it's not clear that spacetime has any possible mechanism by which to generate objects with such properties. All in all, it's much simpler and more in accord with observation, to say that one specific property of fermions interacts with spacetime, than to say that spacetime is mysteriously responsible for all those properties.
I don't like the marble-rolling-on-a-rubbersheet model because it _pretends to_ visualise gravity as spacetime curvature while falling at doing that job. The marble will not follow a geodesic but the actual gravity of Earth below the sheet, particularly at low speeds. A robot ant programmed to move in a straight line might represent a light beam deflected by model gravity and would also do so of the trough were a hill instead.
The illustration of a ball travelling around a curved fabric is just an intuitive way of illustrating the concept of GR. It's only an analogy, and like all analogies it breaks down if you ask too much of it. Now, tidal effects are something altogether different, and a different analogy works better. Imagine that you've got a bungee cord with three equal weights on it, spaced at equal intervals near the end. As you whirl the cord with the balls around your head, what happens to the DISTANCES between the balls? They get longer as the assembly goes faster. That makes intuitive sense, right? What's noteworthy here is that they BOTH become longer, even though you, holding one end of the cord, are applying an attractive force only in the direction toward you. Throughout the length of the assembly, however, there is a FORCE GRADIENT. Inertia wants the balls to go each in their separate ways, in effect pulling the balls away from each other until it balances against the elastic force of the bungee. The balls represent water molecules. As seen from the middle ball, the near and far balls are both pulling away. And you can also see that all of this two-lobed tidal effect occurs because it's taking place in an orbital system. If a watery planet were travelling through space with nothing acting on it, there obviously would be no tide. But if it were clamped rigidly somehow and then you were to rigidly place a large mass nearby, the watery planet would form only one tidal lobe, on the near side obviously.
the biggest question is: what makes the objects move in first place.. afaiu the spacetime only "distorts" the path of objects that are in motion.. but how does it explain gravity as a moving force?
Objects having mass only change their motion as a result of some force acting on them. That's what "makes the objects move in the first place." Otherwise, they keep on doing whatever they were doing, which may or not be nothing. This is one of Newton's original laws of motion. Massless objects, such as photons, in a vacuum move at the speed of light, and only at that speed. But within their own frame of reference (if there were such a thing) they are never moving at all. Nothing "makes them move." It's reality (specifically, the electromagnetic field in the case of photons) that is "moving."
That mass affects space time is true. But gravity is not the curvature in space time produced due to mass. Gravity is a very weak nuclear force. It's effect though always significant is not the cause of gravity. If it was then this means if either the mass of the moon or it's velocity or the mass of the earth or it's velocity was even very slightly different it would crash into the earth. The thought, all things being equal the simplest explanation is always the best is not unscientific.
Imagine a football field that used spacetime curvature -each player is in their own gravity well that is one foot deep and when they have a huddle, the combined gravity wells make the players so deep in the well that they cannot escape to play the game. Notice that the clock is not part of the field. You could learn a lot from a football game. No gravity wells there!!!
So, given things "fall" due to curvature of space and advancement of time, and the Earth pushes us up with a Force that we often call the normal force, is the curvature of spacetime in and of itself akin to a force? Perhaps better worded: given the Earth exerts a Force outward due to pressure, and thus is ever "expanding" to counteract the contraction of spacetime, would that mean that the contraction of spacetime is itself a Force? Or would it fall under one of the three forces of electromagnetic, strong nuclear, or weak nuclear? (Or perhaps the force of spacetime is what's often mistakenly called the gravitational force)
That’s the next step for scientist How gravity fits with the Standadd Model. Quantum Psychics to this day still has no explanation for gravity or how it truly affects the universe. The closest is Super String Theory and the main problem with that is it theorizes our universe is 10 dimensions, 9 of space and one of time.
Gravitational attraction can be described mathematically as a force. Everything works fine, but the force is not fundamental, it's apparent. In this sense it's very much like centrifugal force. Centrifugal "force" isn't a real force, it's an effect of inertia as seen from within a rotating frame of reference. The object in question is just trying to carry on with a constant velocity vector. Similarly, gravitational attraction is the effect of an object trying to carry on with a constant velocity vector, only the frame of reference, namely nearby spacetime, is geodesically distorted. Mass is responsible for this distortion or curvature. So the more fundamental question is what makes this happen. Is THIS a fundamental force? Conventionally it's named as one of the fundamental forces. As such, we expect there to be a particle or field which carries it, called the graviton. But we have not yet directly detected it.
The thing is that seeing spacetime curvature as bowl shaped actually doesn't actually visually explain general relativity accurately. In reality it's about geodesics in space-time, he has made other videos about the real way to visualize it.
i see B got attracted towards A cuz of the curvature alright but what about A? like Newton’s gravity, does A gets attracted to B? it doesn’t look like that from the grid representation… guess i will just have to believe the maths..
What I don't understand in every single explanation like this, is when you place the ball on the grid of spacetime kt's supposed to pull the grid to itself instead of pushing it away
This isn't correct. Who pushed the earth with that initial velocity for it to orbit in space time? The bowl analogy doesn't work because the bowl is on earth so naturally earth's gravity is pulling the marble down. That's just a 2D illustration to help people understand.
One of the worst ways to explain relativity since it requires you to just move gravity off into an imperceptible dimension by representing two dimensional space on a warped surface which Becomes warped because of gravity in our three-dimensional space. You can't use this analogy to reason out how gravity actually works in three-dimensional space without a little extra logical reasoning from an abstract thinker. Most would think Oso a planet causes a defamation in a three dimensional fabric that sits in four-dimensional space and instead of Mass forming the two-dimensional surface of an incline mass is forming a three-dimensional incline. For those who want an actual understanding keep reading. Go back to that explanation with a bowling ball sitting on a piece of rubber suspended by some contraption. If we were 2D Flatlanders living on that rubber sheet we would still need the gravity of Earth from a third dimension we can't perceive in order to provide the force that would send us down the incline caused by the bowling ball. But we can't just move Newton's gravity off into a third dimension. What's a you take that rubber sheet contraption out into space you could cause the same phenomena to occur if you just accelerated your two dimensional rubber sheet through a third imperceptible dimension. That Dimension is time. acceleration Through Time is what causes gravity at least that's how it's described in relativity
how can you insert additional ball for the revolving ball since it is tilted by 5degree does einstein mean an additional space time fabric for that exist tilted by 5 degree that is represented by the earths moon. wew. Newton still the best
Please stop presenting this sort of explanation: Why does the ball B "fall" into the "bowl" in the first place? Because of... gravity! This is Einsteins gravity explained with newton gravity!
Seriously, this answers nothing. Gravity is still a mystery with more unanswered questions than have been answered. I find these comments sycophantic, are you all bots? Mmm I think so.
Tu fais un travail de dingue mec,tu traduis tes vidéos en anglais en plus de les faire en français;en plus de ça le montage et ouf et c'est du contenu de qualité.Franchement tu mérites beaucoup plus d'abonnés.
You do a crazy job dude, you translate your videos in English in addition to making them in French, in addition to that editing and phew and it's quality content.Francely you deserve many more subscribers.
Thank you very much that's very kind, glad you like my work!
It's is Spanish I'm a indian and I'm learning it.....!!@
Oh wow you even pronounced Einsteins name the correct german way! This whole video is perfect
No, it explains gravity by saying things roll down toward pits. He has a better video on his channel however.
@@Neptoid yeah agreed. was my first video by him
In English, the letter "S" does not make the "sh" sound. Therefore, he is already pronouncing it correctly.
einshtein, is that how germans pronounce it? just curious
@@LetsSink yes, it is
You can’t “explain” gravity by the concept of Newtonian “gravity”, your bowl model is only valid due to newtonian explanation of forces and gravity, it would became better if you explained it as objects meets because they are traveling along a curved path which is space-time, so as time flies objects move along that curve and meet eventually
He did another video recently where it is explained w/o the Bowl model
I was about to comment the same.
Yes you're totally right, this video is an introduction to Einstein's point of view and I think the images of the "bowl" or the "rubber sheet" are useful as a first introduction. They help understand that objects attract each other because of the geometry of an underlying object (spacetime) on which they are placed. But if you want more thorough visualizations check out my other videos on General Relativity I have made multiple ones in different levels (this one is for beginners)
@@ScienceClicEN isnt it insanely unlikely that so many planets/moons gained the exact right speed to stabily orbit some bigger object? 🤔
@@ProgressiveEconomicsSupporter Just as likely as all of the other objects that failed to maintain an orbit and crashed into the larger objects. There's a reason why the moon is peppered with meteor craters!
"Why do we fall" "So we can learn to pick ourselves back up"
people fall because they have too much potential energy.
- destroy all your potential, and you will never fall again! XD
@@Verrisin Even photons fall.
@@dsaun777 Destroy all potential of any photons as well. As the last signature of humanity, we should destroy all! If we don't have potential, neither should they!
Yesss
You right I’m picking myself up right now but it’s very hard
You didn't mention following the least time path, which is very much appealing
Einstein's theory of general relativity gives gravity the tag of an illusion rather than a force, which I think is better than the newtonian gravity. But I think we should not forget that newton created his own mathematics in order to prove his theory for universal gravitational force!!😅 Which is truly epic and induces a greater respect to me towards him.
This is a wrong description as it explains gravity with gravity. In the video it is Earth's gravity that forces B to go to the bottom of the bowl. Actually, it is curvature of time that explains why relatively small masses like Earth create attraction. Time goes slower near Earth. There are good videos about this on UA-cam.
Yes, actually I made a video precisely on this : ua-cam.com/video/wrwgIjBUYVc/v-deo.html
However I still think this fabric analogy is good to begin with, as it makes it easy to understand that objects attract each other indirectly, thanks to an underlying container (spacetime), which can be bent and curved by matter.
@@ScienceClicEN That model can perhaps give some idea what is happening (curvature). But the problem is that it does not explain gravity at all! When I first saw this analogy for a long time ago - before internet and UA-cam - I was immediately wondering what makes B actually move to the bowl where the big object A is sitting. That was never explained. I have seen correct explanations only during last few months (I have not tried to search explanations).
In the analogy the thing that replaces gravity is time itself. In a spacetime diagram objects must be moving. This is the real reason why an object follows a curved trajectory.
If 2 objects are stationary in relative to each other, they are still moving, thru time. The object's eventually collide because gravity distorts time and that distortion of time bends each towards each other until the converge. That's my current understanding, where do I go from here?
How do you distort time?
@@abhijithcpreej Gravity bends the time lines towards each other. How it does it I don't know
Time is distorted from mass
things are not running through time - time is running through them
@@hillwalker8741 Interesting concept, I'll put some thought into that one, thanks for posting
I can not get enough of the videos.
Sir please make a thorough video on space-time for complete beginners.
Their General Relativity videos are very good
This video is amazing, thank you so much! I have one question after all: How does this model explain gravitational forces like the moon having an effect on water on Earth?
You see that also SMALL objets make space curvature... thats why
@@suzanaperisa3319 Thank you for the reply.
Why is there a gravitational acceleration for a stationary object then? If there is no initial velocity, the object does not follow a curved path.
Outstanding video and very well explained.
But why is the space around Earth curved like that? Did a wizard do it with magic? title is clickbait
@@alwaysdisputin9930listen to the narrator
@@ninnikk6982 the narrator doesn't say why so you are the one who needs to listen to the narrator
because mass warps and bends the space around it to itself.@@alwaysdisputin9930
Question!
The space time is 3D. Now the 3D space time grid is distorted in all directions around "A". In which plane would the object "B" orbit and why?
Also, this representation suggests that the "B" is attracted and will be colliding with the bottom part of object "A" and not the center of "A".
Spacetime is 4D, not 3D.
As you say, it's distorted by mass. The distortion takes place entirely within the four dimensions of spacetime. No higher dimensions are physically required. In mathematics this is called a "manifold."
en.wikipedia.org/wiki/Manifold
A class mate recommended a video in our physics class about the quantum field theorie and although the subject was imo a bit to advanced for us, i really fell i love with this channel and it's "simler" videos. Great job.
Another thing, what's the music track called playing at 0:38? It's really relaxing and unnerving at the same time and i really want to listen to it.
You are using gravity to explain gravity. They object falls because of gravity not because of the curvature of the bowl. Put the bowl in orbit and the ball will float away.
The elastic sheet is a good first approach to understand that objects attract each other indirectly, through an underlying fabric whose geometry they alter. But yes you're right this model is not very satisfactory as it sort of describes gravity by gravity. Check out my other videos for better visualizations ;)
@@ScienceClicEN I have seen your other video. You are the best channel I have seen so far and I have been been studying physics for over 50 years. I saw the rubber sheet analogy years ago and it upset and confused me. I tried to explain my objections for years and everyone laughed at me. Your video is a good first step but for me the rubber sheet caused a great deal of suffering.
@@TomTom-rh5gk In your opinion, how would you visually introduce the concept to the layman?
@@jacobshirley3457 I like the rubber sheet idea. I saw it in a book by Edward Harrison 40 years ago. It is just that some internet physicists used to make fun of the idea. Most of them aren't very good at being physicists. Like I said before this channel is by far the best that I have seen on youtube.
@ScienceClicEN
My question is not how it works.
I want to know
'what it is'
and
'why it works'!
This is a great illustration of the difference in science between a LAW and a THEORY.
Newton's laws of motion, like all scientific laws, are purely descriptive. They only say THAT something happens under certain conditions.
Einstein's special and general theories are accounts of mechanism. They make the case of HOW something happens. And because we can say HOW something happens rather than merely THAT it happens, we can predict what else SHOULD happen according to the theory.
Wrong. Newton's Law of Motion explains literally everything that involves motion. Einstein’s baseless theories only explain 'gravity' which doesn't even exist. See the Higgs Boson. See the hammer and feather drop experiments.
Newton's Law of Motion perfectly explains the hammer and feather drop test. Explains why clocks in motion are slower. Provides a solution to the twin paradox.
Einstein muddled it all up with his relativity theories and now you are lost and confused. Having to resort to such machinations as warped space and time (fudging the numbers) in order to get relativity to fit reality.
As Nicholas Tesla said. Relativity is a bunch of mathematical nonsense that has hidden the underlying errors and confused people.
Look how confused you are when you don't even understand 'gravity'.
It doesn't explain why though. Distorting the grid could equally well cause objects to be repelled, or go pretty much anyway except a straight line. Was expecting a better answer
There is another video on the channel that explains this better
He would have gotten into the math. Earth and the moon has a speed thru space. If the moon has the right speed for its mass it will constantly miss earth at an even rate, we call this orbiting. The international space station does this by achieving 17,000mph at a certain altitude, always falling, but missing earth in space-time. ➿〰️🔄
@@alexgmihai242 _"There is another video on the channel that explains this better"_
Yes but even that video just says Earth is sucking in spacetime like a vacuum cleaner without saying WHY it is sucking spacetime like a vacuum cleaner. It is unknown to humanity why it does this. No human knows why we fall. The title of the video "Why do we fall?" is clickbait. The question is not answered & nor can it be without new physics
The Galilian transformation most then also work in the Electric/Magnetic wave, meaning that the centre and the wave horizontal or verticaly will end up at the same time, in the centre. There is no time differance, it just looks like that. It matters not if you move diagonaly away or in a parabool, you will alway's see your mirror equation in the Galilian transformation. 😮
One doubt....
A marble in a bowl falls... Or the way that moves inside the bowl is because of the gravity... Acting on the marble downward.... In gravity free space this will not happen.. then how we can say that the space time acts like the marble in the bowl... In our current scenario...???
Your description of B moving towards A is using gravity to describe gravity. This is why the rubber sheet analogy is so wrong. If gravity was simply the curving of space then nothing would fall, it would simply stick wherever you put it.
The explanation of gravity must include an explanation of time to make sense, because its spacetime that warps, not just space. Time slows down the closer to A you get, so there is a time gradient across any object in a gravitational field. e.g the part of B that is further away from A is moving through time faster than the part of B that is closer to A.
The real question tho is why (and how) a mass warps spacetime at all.
Yes but it’s a beginner intro to understand the basics or concept
The other video heh as touches on your comment.
GREAT FINALLY FINALLY SOME ONE DID IT SO MUCH FINESSE IN THE PRESENTATION OF PHYSICS
Aaand it's inaccurate. There's actually a great video by the same channel that explains it way better
@@commenturthegreat2915 it is inaccurate
@@commenturthegreat2915 What channel bro ?
@@commenturthegreat2915 how is it inaccurate?
@@FOXTROTALPHA2412 The way he explains it in the video suggests some sort of directional force is acting upon the falling objects through a 4th dimension, pulling them towards the "bottom of the bowl". This is inaccurate. The whole point of Einstein's version of gravity was to show that objects in freefall aren't actually accelerating, but are stationary on a grid that is compressing.
Aren't you trying to explain gravity by gravity itself? Space-time is a 3D grid + 4th dimension (t), then you're explaining apple falling story with earth/sun example on 2D like stretched space-time fabric ?
The channels logo is the same as the logo for an app called "Quantum" in google play store, is it a coincidence?
Man, you have some f**king brilliant explanations and showcases. Add to it your perfect voice, and the best physics videos are born... 👍
From the constructs presented here I can’t see any particular advance beyond Newton’s conceptions or anything else’s besides given for the ‘cause’ of gravity as you put it. I don’t know if I have it right but I am not sure that Newton gave a cause for gravity or ever could since he regarded it as a ‘general effect’ - although the operation of this effect was quantifiable and this he provided with his inverse square formulation for it - boiling down to doubling the attraction for each halving of the mutual distance of centres. Since the effect is so much greater at the surface than any distance away and dissipating with distance at the same rate as that for attraction - personally have never seen what is meant by ‘space-time’ and the depressed trampoline surface image provided to explain it. You place two snooker balls ever closer together and at the finest approximation a magnetic effect takes place and they ‘click’ together - but what’s that to the larger spaces of any sized table on which play takes place? I’d like to know what is mistaken in this view.
the bowl analogy is not very satisfying.. just because it implicitely uses GRAVITY as the force to make the marble roll down.. you cant explain gravity by using gravity
Einstein was looking for little children to sell a story to and he found the physics community. An objects 3 dimensions change with time but space and time are different things defined by humans. Gravity is just a phenomenon caused by the ejecta of the universe in the form of profuse superluminal fundamental particle of extremely low mass that comprises the mass of elementary particles forcing objects against other objects that shield each other from the contralateral universal hemisphere ejecta. There is only one force in the universe, the strong repulsive nuclear force which itself is a consequence of the kinetic energy of the fundamental particles emanating and entering the core of all long lived elementary particles and bosons.
Still confused by the spacetime "grid". It's always depicted as a 2D sheet, horizontal in the image. In reality it surely works in three dimensions?
yes. the 2d sheet is just an analogy.
and the idea of warping is wrong - less new spacetime is being produced near massive objects
Great explanation! Thanks
Why do we fall? We don't, we are standing still, there is no reason for us to move. What did you think? That gravity was a spooky force acting at the distance? The Earth however has a reason to move, its atoms are pushed apart. The Earth expands. And I guess it will always catch up to you. Why doesn't the Earth seem to grow bigger? Well it is constantly getting scaled down because of a bend in spacetime.
If it's constantly getting scaled down then it will never catch up to you. You're trying to have your cake & eat it at the same time. You're trying to say "the floor moves up but it doesn't move up".
The floor is moving through time at the speed of light c. It got this movement probably at the Big Bang or thereabouts.
When we start to fall, there is a relative movement between us & the floor. The space between us contracts until we connect with the floor. You can say we're stationary & the floor moves up. That's fine. & you can also say we're moving & the floor moves down. That's also fine. But both are mere labelling similar to saying "people in Australia are upside down". What's reallly happening i.e. the invariant thing is that the spacetime between us gets smaller.
It gets smaller because the Earth's mass sucks the spacetime like a vacuum cleaner. No human knows why this happens. Therefore no human knows why we fall. However physicists do know 1) the spacetime contracts & 2) both the floor & us are moving through time at the speed of light. We are moving along a straight line into the future.
As the spacetime contracts this straight line curves around. This means that instead of moving towards the future we start to change direction. We follow a curve. This is like how a car travelling north will start curving west IF the road is curved. However humans are blind in that we can't see the time dimension. Therefore it seems like we fall in a straight line until we connect with the floor. It's like we can't see north-south so we just see the car stationary & then we see it move westwards a little bit, then it accelerates westwards. But the car isn't moving just west like that. It is following a curve.
Sorry to explain unclearly without diagrams & animations
@@alwaysdisputin9930Does that mean that when an apple falls, the apple is actually still, but the floor is accelerating up to meet the apple AND at the same time the apple moves in a curved time, so in a curved line pointing at the center of the earth?
Why do we have ellipsoidal orbit and not circular?
Thank you so much for making a sister channel en español. Quiero conocer sciencia en inglés y español porque tengo amigos que no hablan inglés. Estoy aprendiendo español pero necesito vocabulario y gramática. :)
1:56 isn't it like explaining gravity with the help of gravity?
Why B moves towards A?
The curvature of the space-time is distorted, so that the physical geometry tends towards objects with high mass. The usual analogy is misleading I agree, it's difficult to represent the 3d geometric distortions visually. Insidd the event horizon of a black hole, the geometry is so distorted that all directions lead into the center of the black hole.
There's no point at which something can orbit perfectly though, right? It's always going to be falling toward or falling away?
True. Even if the orbit began perfectly, the gravity from other objects will affect that perfect orbit.
Great video dude
Thanks!
What if objects with mass lagged behind in time so if you look at a space-time diagram it would look delayed and further back in time, that would explain time dilation as it warps the fabric and also gravity since it bends the time axes of other masses towards it and vice versa
what do you mean lagged behind in time?
Je suis impatient de voir la nouvelle vidéo ! :D
It will be out in at max two weeks I think ;)
Please use accurate visualization for bending of space.
Haha. Ouch!
... although you’re right. Lol
Seeing this model (pushed down fabric) irks me everytime.
@@akinoreh What is the correct model to use?
See his other video
Very helpful video. Thank you much
How do we know the amount of curvature due to a specific amount of matter?
Just like we know the amount of force due to a specific mass in Newton's theory: with an equation relating both concepts.
For Newton's gravity you have the Law of Gravity: F = G Mm/r^2 (in module)
For Einstein's General Relativity you have an analogous equation, though a much more mathematically-complicated one: Einstein's Field Equations, which instead of using vectors to represent forces it uses tensors, kind of a generalisation of vectors.
Just like Newton's law tells you how much force there is given the masses and the distance between them, Einstein's Field Equations tell you how and how much the space-time curves given a certain distribution of energy.
Albert Einstein is probably the most fascinating person to me. I understand the explanation however, this explanation doesn't explain everything. Many questions can challenge this theory.
wonderful explanation
How do we know mass causes warped space (gravity)?
My postulate is that warped space (gravity) causes mass, fermions.
And we now know that gravity waves travel across space.
Gravity waves propagate IN spacetime, not through it.
While this distortion and mass are so closely related that it might be hard to say which is the cause and which is the effect, we can use some additional clues to help us decide.
Fermions have properties in addition to mass. Spacetime doesn't account for these properties, and moreover they are highly localized to each fermion and invariant with each instance of a fermion.
Conversely, spacetime has no known properties of itself, other than the geodesics of GR. So it's not clear that spacetime has any possible mechanism by which to generate objects with such properties.
All in all, it's much simpler and more in accord with observation, to say that one specific property of fermions interacts with spacetime, than to say that spacetime is mysteriously responsible for all those properties.
I don't like the marble-rolling-on-a-rubbersheet model because it _pretends to_ visualise gravity as spacetime curvature while falling at doing that job. The marble will not follow a geodesic but the actual gravity of Earth below the sheet, particularly at low speeds. A robot ant programmed to move in a straight line might represent a light beam deflected by model gravity and would also do so of the trough were a hill instead.
If it's just a ball going around a fabric then why is there a High/Low tide on the ocean? There has to be a physical connection.
The illustration of a ball travelling around a curved fabric is just an intuitive way of illustrating the concept of GR. It's only an analogy, and like all analogies it breaks down if you ask too much of it.
Now, tidal effects are something altogether different, and a different analogy works better. Imagine that you've got a bungee cord with three equal weights on it, spaced at equal intervals near the end. As you whirl the cord with the balls around your head, what happens to the DISTANCES between the balls? They get longer as the assembly goes faster. That makes intuitive sense, right?
What's noteworthy here is that they BOTH become longer, even though you, holding one end of the cord, are applying an attractive force only in the direction toward you. Throughout the length of the assembly, however, there is a FORCE GRADIENT. Inertia wants the balls to go each in their separate ways, in effect pulling the balls away from each other until it balances against the elastic force of the bungee.
The balls represent water molecules. As seen from the middle ball, the near and far balls are both pulling away.
And you can also see that all of this two-lobed tidal effect occurs because it's taking place in an orbital system. If a watery planet were travelling through space with nothing acting on it, there obviously would be no tide. But if it were clamped rigidly somehow and then you were to rigidly place a large mass nearby, the watery planet would form only one tidal lobe, on the near side obviously.
8兀G(Tuv)/c^4
8兀G(Ee)/c^4
8兀G(E/c^2)(e/c^2)
8兀GMm
2(4兀r^2)GMm/r^2
2(ball-face)gravity-formila
two thing(all-round)gravity
the biggest question is: what makes the objects move in first place.. afaiu the spacetime only "distorts" the path of objects that are in motion.. but how does it explain gravity as a moving force?
Objects having mass only change their motion as a result of some force acting on them. That's what "makes the objects move in the first place." Otherwise, they keep on doing whatever they were doing, which may or not be nothing. This is one of Newton's original laws of motion.
Massless objects, such as photons, in a vacuum move at the speed of light, and only at that speed. But within their own frame of reference (if there were such a thing) they are never moving at all. Nothing "makes them move." It's reality (specifically, the electromagnetic field in the case of photons) that is "moving."
wow , now only I understood gravity as per Einstein...very good graphics....gravity is not attraction
That mass affects space time is true. But gravity is not the curvature in space time produced due to mass. Gravity is a very weak nuclear force. It's effect though always significant is not the cause of gravity. If it was then this means if either the mass of the moon or it's velocity or the mass of the earth or it's velocity was even very slightly different it would crash into the earth. The thought, all things being equal the simplest explanation is always the best is not unscientific.
Imagine a football field that used spacetime curvature -each player is in their own gravity well that is one foot deep and when they have a huddle, the combined gravity wells make the players so deep in the well that they cannot escape to play the game. Notice that the clock is not part of the field. You could learn a lot from a football game. No gravity wells there!!!
Very interesting. @Nathan Oakley 1980 sent me. Thanks!
we're assuming there's some sort of field and the universe is flat ...so I believe quantum theory is trying to explain that field right?
@NathanOakley1980 is doing a review of your video. Look forward to a response from you possibly.
Why is mass distorting spacetime in the first place?
we do not know as of yet
doesn't explain what the attraction forces are
So, given things "fall" due to curvature of space and advancement of time, and the Earth pushes us up with a Force that we often call the normal force, is the curvature of spacetime in and of itself akin to a force?
Perhaps better worded: given the Earth exerts a Force outward due to pressure, and thus is ever "expanding" to counteract the contraction of spacetime, would that mean that the contraction of spacetime is itself a Force? Or would it fall under one of the three forces of electromagnetic, strong nuclear, or weak nuclear? (Or perhaps the force of spacetime is what's often mistakenly called the gravitational force)
That’s the next step for scientist
How gravity fits with the Standadd Model.
Quantum Psychics to this day still has no explanation for gravity or how it truly affects the universe.
The closest is Super String Theory and the main problem with that is it theorizes our universe is 10 dimensions, 9 of space and one of time.
Gravitational attraction can be described mathematically as a force. Everything works fine, but the force is not fundamental, it's apparent.
In this sense it's very much like centrifugal force. Centrifugal "force" isn't a real force, it's an effect of inertia as seen from within a rotating frame of reference. The object in question is just trying to carry on with a constant velocity vector.
Similarly, gravitational attraction is the effect of an object trying to carry on with a constant velocity vector, only the frame of reference, namely nearby spacetime, is geodesically distorted.
Mass is responsible for this distortion or curvature. So the more fundamental question is what makes this happen. Is THIS a fundamental force? Conventionally it's named as one of the fundamental forces. As such, we expect there to be a particle or field which carries it, called the graviton. But we have not yet directly detected it.
WOW AMAZING VIDEO I HAVE WATCHED MANY OTHER VIDEOS OF 15 MINUTES AND THIS IS THE BEST ONLY 3 MINUTES!!!
i hope u to continue
But how the planet obtain the sufficient speed for being able to orbite without falling into the star
How is it possible,is that space has up and down ?How that bowl theory ?I don't understand Im 12
The thing is that seeing spacetime curvature as bowl shaped actually doesn't actually visually explain general relativity accurately. In reality it's about geodesics in space-time, he has made other videos about the real way to visualize it.
i see B got attracted towards A cuz of the curvature
alright
but what about A? like Newton’s gravity, does A gets attracted to B?
it doesn’t look like that from the grid representation…
guess i will just have to believe the maths..
God bless u brother.. I have watched all ur videos.. It clears all my doubts.. Thanks a lot
What I don't understand in every single explanation like this, is when you place the ball on the grid of spacetime kt's supposed to pull the grid to itself instead of pushing it away
This isn't correct.
Who pushed the earth with that initial velocity for it to orbit in space time?
The bowl analogy doesn't work because the bowl is on earth so naturally earth's gravity is pulling the marble down. That's just a 2D illustration to help people understand.
But any one can describe what give the earth n planet speed continuesly
One of the worst ways to explain relativity since it requires you to just move gravity off into an imperceptible dimension by representing two dimensional space on a warped surface which Becomes warped because of gravity in our three-dimensional space. You can't use this analogy to reason out how gravity actually works in three-dimensional space without a little extra logical reasoning from an abstract thinker. Most would think Oso a planet causes a defamation in a three dimensional fabric that sits in four-dimensional space and instead of Mass forming the two-dimensional surface of an incline mass is forming a three-dimensional incline.
For those who want an actual understanding keep reading. Go back to that explanation with a bowling ball sitting on a piece of rubber suspended by some contraption. If we were 2D Flatlanders living on that rubber sheet we would still need the gravity of Earth from a third dimension we can't perceive in order to provide the force that would send us down the incline caused by the bowling ball. But we can't just move Newton's gravity off into a third dimension. What's a you take that rubber sheet contraption out into space you could cause the same phenomena to occur if you just accelerated your two dimensional rubber sheet through a third imperceptible dimension. That Dimension is time. acceleration Through Time is what causes gravity at least that's how it's described in relativity
Thnkzz brother 🔥
Can you please continue posting videos in englisch!
Last part wrong, since the earth and moon are moving through space very fast, the moon can never reach the earth
I thought planets orbit the sun because the planets are technically following a straight line distorted into a circular shape in spacetime?
This video is meant to introduce beginners to the concept. For example, both objects would move towards each other, but it isn't shown here.
Great!
nice
Ohh, how he discovered that thing..
So we can learn to pick ourselves up...😶
Batman begins theme intensifies
What I’m trying to understand is ,if their are no planets would their be gravity?
if there is nothing there is no gravity
how can you insert additional ball for the revolving ball since it is tilted by 5degree does einstein mean an additional space time fabric for that exist tilted by 5 degree that is represented by the earths moon. wew. Newton still the best
Alberts is the right one.when you knuckleball a soccer ball there is no rotational force
Alright all the planets travel in orbit....But why it's in elliptical and not proper circular🤔
But why is the space around Earth curved like that? Did a wizard do it with magic? title is clickbait
So why the Moon don't falling at Earth ?
Another great introduction to General Relativity can be found here: ua-cam.com/video/z1o32hKx5hI/v-deo.html
Where is that sorry apple?
Where is that sorry apple?
You ended with a black hole. Apples can't do that.
But how does the planet get that much speed?
From thé solar system to up the nebula make time to créate galaxies and solars system
...so i have been saying 'Einstein' wrong my whole life :'
This is... Bad... massive objects do not create any bowls, they pull spacetime into themselves
Please stop presenting this sort of explanation: Why does the ball B "fall" into the "bowl" in the first place? Because of... gravity! This is Einsteins gravity explained with newton gravity!
Ainshtain
Cuec
But Earth and the moon are not in a two-dimensional plane. I hate this analogy and it's everywhere on UA-cam.
If you want a more accurate visualization I have done a more recent video called "A new way to visualize General Relativity", you might like it more
Bro discovered the 4th dimension 😳
👏🏻👏🏻👏🏻
This didn't explain shit. WHY does mass warp space time.... Like WTF is gravity innit?
Poor Apple is being the victim in Physicist's theory
asas
Seriously, this answers nothing. Gravity is still a mystery with more unanswered questions than have been answered.
I find these comments sycophantic, are you all bots? Mmm I think so.
Einshtein
Einstein was a plagiarist.......
This is not a good explanation...the whole grid and ball thing is so redundant now