Why do you age slower closer to a black hole? (An intuitive approach)
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- čas přidán 25. 04. 2024
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Why do you age slower closer to a black hole? How doesn Einstein's theory of relativity intuitively explain gravitational time dilation?
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Red Dwarf has an episode where they had to communicate during time dilation, I just can't recall which series it was. Maybe it was an audio book come to think of it? 🤔
Hello mahesh sir, nice explanation. Does time dilate more inside the earth compared to that on the surface?
Can you please make a video on polarization of light.
* Ek X Banda h voh earth se 9000 light years dur h ...
* Uske waha gravity Kam h
* Humaare yaha zaada
* Humare yaha usko 9000 saal baad dekhenge toh woh ...
* 6-7 hr jeeke ...
* Par uski aging fast hogi ....
* kya yeh theory sahi h ?
@@Happybro91 Earth sucks space, like a vacuum cleaner sucks air. And since sucking is omni-directional, the space speed (relative to Earth surface) is greater near Earth than the speed at high attitude. As a result, a body near the Earth and another body at high attidue moves with different speed through the sucking space. So, according to special relativity, time ticks differently for them.
If you'll take a flat infinite surface with uniform gravitational field, there will be no difference in grativy at different attitudes. So, there will be no difference in time flow. In other words, time flows differently at different attitudes because Earth is round.
Never stop making videos even if u get less views,some channels r really good and this is one of it
Fewer views...
Fun fact: Watching this video on Miller's planet would cost you ~2.2 Earth years.
What?? 1 hour on Millers planet was 7 years… this video is 19:17 minutes long.
@@warhead213 60 minutes = 3600 seconds = 7 years on Miller's planet
7 years = 220752000 seconds
This video is 19 min 17 sec = 1157 seconds
So we can do simple math;
1157 / 3500 * 220752000 = 70947240
70947240 seconds = 2.25 years
10:02 "That's what I am talking about!"
I can't stop smiling. Your explanations are always to the point and easily understable, but these subtle comments, they are in the next level!!
5:35 my brother, I love watching these type of videos, although I may not understand 90% of it.
Let me just say it 5:30 mark, the way you broke down the apple falling towards the ground versus the ground, moving in the path of where the Apple was going just blew my mind.
I never make comments on pages, but I’m taking time to tell you, bravo. I’ll be following your page for a long time!
being on earth makes you age "slower" too. no matter how 'slow' it gets you will always experience a normal flow of time from your perspective. like the water planet in the movie interstellar. they experienced a normal flow of time from their perspective.
I am more confused than before watching this video
For the individual the perception of time will always the same but for the observer the time changes based on time dilation caused by moving at extreme speeds or extreme gravity
So the key To eternal life is moving fast 😄
@@genghiskhan9200Or maybe don't get a nosebleed...that's what finished Genghis apparently 😁
How do you explain everything in one sitting? I haven't noticed any cuts, it's just you talking straight for 20 minutes without missing any points and with accurate emotions and energy. How is it even possible? You are a great teacher. Keep doing what you do. I cannot thank you enough. Your love for physics is unmatched. And ahhh I can finally watch Interstellar and actually understand a few things!
The concept of these physics are quite profound. Without time, motion becomes impossible. This also means that motion and speed are affected by gravity in crazy and unexpected ways. Simply being in strong gravitational field does indeed affect aging. So when we “measure” the age of our universe which is expanding, was a year really a year when the universe was more dense? It certainly seems that 1 year very soon after the Big Bang could have actually been thousands or even millions of years relative to a year that we perceive now due to the gravitational affect of so much matter being in a smaller volume of a more compact universe.
This is by far one of the best Physiscs explantion channel that I have ever seen...
What? This video is horrible! You must be a fan. A fan of pseudoscience! Put down the pseudoscience and study astronomy. Read more nonfiction. Dictionary. Encyclopedia.
I think Einstein would be proud of you.
Every. Single. Video. I am BLOWN AWAY
Blown away by his imagination? Other than that, you need to read more nonfiction. Dictionary. Encyclopedia. Put down the pseudoscience and study astronomy. This guy is a clown!
@@JusticeLeGrand10101 there’s no way your aren’t trolling 😭
Love your vids that breakdown complicated topics into easily understandable chunks!
That’s sad because if you understood this video, the only thing you understood was his imagination. Put down the pseudoscience and study astronomy for yourself. This guy is a clown! this CZcams video is promoting misinformation. read more nonfiction. Dictionary. Encyclopedia. put down the pseudoscience and study linguistics. silly Human!
Listen to me, you sir are the best CZcamsr, period. Please never stop making videos
This is the type of channel that should have 50 million subscribers. Don't stop what you're doing. You're one of the best at it. I've watched more videos on these subjects than I can count, but after watching only a few of yours, it all makes so much more sense. Not only that, I was able to easily connect other videos you made to related topics and they all come together in my mind seamlessly.
It reminds me how my highschool chemistry teacher couldn't teach me something in a year that a college professor described in one sentence and I still remember it over twenty years later.
I also want to add, the best part of your presentations is you ask out loud exactly what most of us are thinking in that moment and makes it seem as we are there with you.
Love how passionate and engaging you are! Your visuals and explanations helped me understand this at a deeper level so thanks🤙
Best advice you provided us at the end of the video. I will definitely try it. And I love this video so much. Now I feel satisfied to know this concept 😊
Brilliant video - love the channel and your passion for physics!
I would love a video about time dilation and quantum entanglement. Maybe that's just a special case of the relativity of simultaneity, which you've already covered. Anyway, I'd love to see one of your incredibly explanations on that topic! And just in case I do actually have your attention, I'll take the opportunity to say thanks for all the great videos. I agree with all the innumerable praises I've read in the comments section on all of your videos. Keep up the great work, whatever topics you choose to pursue!
Thank you Mahesh, for showing me the connection between the cycloid (a rolling, rotating circle) and gravity in General Relativity I was looking for for 4 years. And it turns out to come from the master himself, Einstein! I love it ❤
This is amazing intuition into a very hard problem. Great job
I’ve heard other explanations about this stuff…but yours seems the best..thank you!!
Loved using your relativity series to expand my knowledge and then finally intuitively demonstrate the concept of gravity being a fictional force to my friends. I made the flat spacetime graph, made the cone graph, and a figure to show Einstein's clock in like 15 minutes in a late night discord call. Started with Galileo's transformations on a train to introduce relative velocities, then used a thought experiment about what happens when Galileo lets go of the ball from the leaning tower of Pisa in terms of Newtons first and second laws of motion first from Newton's classical perspective where the ball begins to accelerate due to an applied force, and Einstein's where the ball remains at rest. Using your graphs, I showed how the equivalency principle shows us Einstein's alternative explaination for our observations. It was incredibly fun for everyone and I thank you for your efforts.
For the sake of time (pun intended) and my own limited intuition I asked them to accept time dilation and that we observe it now in many ways but I suppose ill be threading in an imaginary space station next time.
Its still hard for me to take a leap in this demonstration from objects accelerating toward eachother with zero relative motion to the idea they could accelerate away from eachother without relative motion. Luckily, I live in an area with gravity so I'm confident it happens 😂
Your whole comment was based on imagination just like this video. Science rebukes imagination. Science is humans observing nature. Time, light and sound works simultaneously as nature. for example, we experience time through our star, the sun. we are our star. your imagination like this video is irrelevant. silly pseudoscientists! put down the pseudoscience and study astronomy. read more nonfiction. Dictionary. Encyclopedia. put down the pseudoscience and study linguistics.
@Mahesh_Shenoy I have a doubt in your video of train paradox, consider a situation where there is another door/ sensor, before the mid point of tunnel. Then from the train's perspective, the order of doors closing/ sensors receiving messages will be right to left. Now if you look at the same scene with a stationary perspective, you will see that the new door/sensor closes first then the left and right door closes simultaneously.
Now let us take the doors/sensors as events 1,2,3 from right to left respectively. Therefore, the order from the train's perspective is 1-> 2-> 3. But from the stationary perspective the order will be 2-> 1=3. So my doubt is that how could the order of events change. Also if there was another train moving opposite to the motion of this train it would see the order of events as 3-> 2-> 1 ( reversed ).
Duse, you have such a fresh way of explaining things! I've watched hundreds of science videos, and so many of them repeat the same words as each other, but I'm always thrilled to find a fresh perspective~
Mahesh you're simply one of my favorite youtuber! found you just this year but totally in awe.
This was a really nice video. Easy to understand, taking us through a series of logical steps. Good analogies.
I can't get enough of the intuitive explanations. The model is inverted in respect to the observer to simulate gravity so the direction of the simulated gravity is also inverted in respect to the observer. I almost got hung up on the difference between the planet or black whole from the ring model and which way the arrows point.
he is a gem to the world we need to protect it!!!💖💖
Reall really great video and explanation. For us mortals who can't imagine 4d spacetime (pretty much everyone), this gives us a glimpse as to why time shows down in a gravitational well. Bravo Sir 👏 👏
A video on this topic was really needed...
thankyou very much sir ❤
This is the second video I've watched on this channel.
Both times I feel absolutely certain that I now understand this stuff, right up to the point that the video ends.
As soon as the video ends I go straight back to not understanding it at all.
Amazing content as always!
The qualiry of your contect is way abouve channels even like vertasium. Thats what I feel. I had cofnisons on relativity for many years. Thanks to you that things are getting clear
Thanks for the video! You're videos are so helpful on trying to understand the universe.
Just don't stop to keep building up the intuition videos
And I'll ask to even make videos about some other physics topics like i am very in statistical mechanics and quantum mechanics
Although I am enjoying the series 😊
Mind blowing animation sir
Thank you. You are an amazing teacher.
Didn’t realize the Feynman technique was called that! Whenever I learn something or am doing homework, I try to pretend like I'm the teacher explaining the homework problem to students and it helps me learn a lot more.
So yeah, that technique is applicable not just for youtube videos. Try it out if you're struggling in a class
Thank you so much for this. I just watched it with my 10 year old and she now has a much better grasp of gravity and time. I do now as well. ❤
In my opinion this explanation is an elusion as usual. It is true that both speed and gravity slows down time keeping but as it has never been explained how a big mass bends space time more than a small mass without having some kind of influence (force) from the mass I can't see why we might not as well use the old explanation.
If you have an oscillating (like a pendulum) electro magnetic signal in any cell, atom or even the smallest particle then if it moves it will take longer for the signal to go from one side to the other and back for the oscillation. This will slow down time keeping. The faster the slower but it is not linear.
It is there fore no big deal that if gravity influences light (as I believe has been found although I am still skeptical)) and light is an electro magnetic emission then time should be measured slower in a strong gravitational field.
Mahesh is very smooth and fast in his explanations just like a magician. One must take it very slowly, stop often to think about it and then verify and I must admit it is difficult. Albert Einstein must have been the same as many of his explanations supposedly where not even his own.
Just discovered the channel and while I was watching the previous black hile video, a new one came out. What a coincidence?
so time seems to move faster when watching these videos?? 😂
Hey thanks for this awesome content. Can you make a video about Orbitals and related stuff. I really want to have an intuitive understanding about orbitals.
Please don’t stop making videos, You cure depression.
The way I imagine it: the center of the circle is the black hole or point or intense gravity, and any circle you draw around the center is a timeline. So, to draw a complete circle, even though it may seem like line physical lines take the same amount of time to be drawn, the "length" of time (the circle) is longer.
I love your videos, thanks for the explanations!!
Thank you. Terrific video. I've been saying for some time that spacetime curvature is, in fact simply time dilation. When light travels through space it is always travelling in a straight line from its own point of view and what makes it lens and bend to an observer is in fact time dilation, to keep the velocity of light constant and dilate time to another frame it also passes you effectively curve the distance between them. It's an illusion, spacetime curvature is just a topography of time dilated frames of reference.
But this revision of Einstein's explanation using relativistic acceleration explains it much better than I do. Time dilated frames of acceleration reference as topographical gravitation is the term I'll use from now on.
Mahesh Sir, I'm a big fan of yours. I have 2 physics questions.
1. A piece of ice is floating in a glass full of water. After the ice melts, will the height of the water increase or be equal?
2. Suppose I'm carrying a large stone in a small boat in a swimming pool. If I throw the stone in the pool, will the height increase or be the same as before?
By the way, I learned the Archimedes law from your video in Khan Academy. Absolutely amazing!
My village in Uganda is poor. We enjoy your videos. Thank you.
Thanks now I have a better understanding for what time is.
These are so interesting and fun thank you!
Wouldnt it be easier to simply say that the speed of light is not constant and that light is acted upon by the force of gravity, such that the higher the gravitational pull the slower the speed of light. That would explain the desyncronization of the clocks in a similar way as the displacement model. In other words, the clocks are measuring the time it takes for a particle to go from point a to point b, to make the clock tick slower either increase the distance or decrease the speed of the particle. Relativity posits that we increase the distance, nuetonian physics suggests that we slow the particle.
I've stumbled across one gap in the explanation that bugs me. In the spaceship, what really caused the time dilation isn't acceleration as such, it's speed. So to understand why gravity “causes” time dilation, we have to show that massive bodies somehow make everything nearby “move” faster. You've hinted at a solution out by showing that motion is a way to combine acceleration with constant distances, but it would be great if there were a way to demonstrate it more directly.
"..isn't acceleration as such, it's speed". That's from the inertial perspective. From the perspective of the people inside the ship, they will attribute it to the centrifugal force.
You can imagin it like space itself is flowing inward towards the center, like water into a sink hole. When you are not resisting the flow you are under a free fall. And you are moving with your local spacetime but when you are on a surface standing, then you feel the force down at your feet , here you are resisting the flow of space hence you are moving through space , also the faster you move through your spacial dimension the slower you move through the time dimension.
Wow I came here to write _exactly this_.
Wait, are you me?
@@shrivatsa8604
this is a much more intuitive rationale than perpetuating the absurdity that all mass is under constant acceleration outward.
@@youngguns2121 👍🏻
I've still never fully got it. I understand that it slows time down, dang near to stopping it in a black hole, but I always can't help but think from an outside perspective. If I am watching a person near a black hole, and one way out in space, they should both age 24 hours on my clock if I watch them for 24 hours right? Just never understood how one covering more distance affected time. Time is only particles moving position, even objects setting dead still have subatomic and atomic particles, cells, etc. moving all over. So does heavy gravity just slow ALL particle movements?
What would happen if the people near the center of the rotating space station started recording 2 videos - one streaming live, the other a stand-alone space smartphone that begins recording everything live at the center of the ship and keeps recording continuously whilst traveling to the outer ring (and has storage and power that will not run out). The streaming signal is broadcast while the space smartphone is continuously recording live the entire trip (and is put in a little escape pod and ejected toward the outer edge or traveling inside the ship on a little delivery Robot if it’s all connected and can reach the outer edge people). When the outer edge people start receiving the streaming signal, what do they see? Are there gaps in the broadcast signal, or does it show the center ship people in fast forward gradually slowing down, or what exactly would it look like to the outer ring people seeing it?
Now for the space smartphone: When they receive the space smartphone they stop the recording (which has been recording without stopping the entire trip from the center people to when it reaches the outer edge people). They now begin playing back the recorded trip…does the video, now playing in their reference frame but recorded from its point of view in its reference frame from the center to the edge, what would that video look like to them? Would it start out playing super fast and gradually slow down or just be a super long, super boring video of endless hallways and passing by in “normal speed”?
And just to be extra complicated, what if there were 2 devices recording, one digital and one on an old analog film recorder with rotating gears and wheels and endless videotape - how would the digital video compare to the analog recorded video with both now playing in this outer ring reference frame but recording all the time between? Does digital recording have any difference to the analog recording that had gears/wheels while recording? From the recording device’s perspectives time has just always been the same, but when the people in the outer ring frame of reference watch the recorded videos,starting the playback of both devices at the same time and watch them side by side…do they see video and hear sound that runs at different speeds from the beginning to the end? Do the 2 devices vary compared to each other? Or is just a boring standard speed video on both devices? How does the recorded video compare to the streaming video (if it had been recorded by the outer ring people while streaming and now also played back starting at the same time as the devices that travelled from the center to the outer ring? Hopefully this is an interesting thought experiment and not so obvious that I dont later think “why did I even ask that?” :-) And thank you, love this sort of thing; thumbs up and Sub’d! :-)
Hey Mahesh - today I understood how the ground accelerates to meet the apple! Wow man! Check point 4:20
Loving every video of yours... ❤❤❤
Your channel is the best man. Thanks for the vid
omg!! the best explanation ever!!
Your visual representation is wrong. The two land surface should be outward and the force that pull in is centripetal
"The speed of light is the same in all reference frames, that is why [we have the time dilation effect we call gravity]. Do you now have a better understanding [...]?"
No. Like you said, it's like explaining why an apple is red by saying it's a red apple. How does mass cause the path to extend?
Damn! Even though I knew that time is relative, subconciously I still believed in the newtonian model of Gravity and time. Your approach broke my entire concept of time and you won't believe how happy I am right now! Thank you for shattering my concepts and bringing me into the new realm of relative time.
Well explained 👍
Great video as always!
Thanks, waiting for your video :)
Subscribed bro! Amazing channel 👏
I've had a question I'm hoping you'll address about approaching the speed of light or the event horizon of a black hole. The science communicator channels all seem to agree that when your ship exceeds the speed of light you disappear but they don't ever mention red shifting during the process. It seems to me that it wouldn't be an instantaneous switch from visible to gone, and that after the boundary is reached(supposing it were possible) you would red shift into invisibility as your ship accelerated further. From the point of view of the the ship going into the black hole it would look like the rest of the universe was moving on and aging more and more quickly, I think, and an outside observer would see time slow down and stop for the ship then it would appear to fade into infrared until it became undetectable. What are your thoughts?
Edited for clarity*
The first part is unclear, specifically, what you're talking about when referencing matter moving at or faster than the speed of light.
A ship approaches the horizon, the distant observer will observe the luminosity and frequency to sharply decrease and the ship vanishes.
Yeah, the red-shift happens exactly in proportion to the time dilation _because they are exactly the same thing_ A lot of pop-sci entertainment explanations of relativity are bad because their sources are other pop-sci explanations, and it's a big game of telephone and no one ever bothers to actually read a physics textbook.
@juliavixen176 thanks for the input! It helped me feel like I wasn’t crazy.
I have a doubt... I don't know whether sir answered it or not anyways I can't find it or understand it(Also, my english isn't that good)....
My question is that, space curvature is a visual way to represent objects slowing down due to gravitational time dialation right?..... If so then the curvature i.e, used as a way to visually represent the slowing down of objects, how does that bend the path of light ....
According to sir's previous videos it is clear that due to time curvature and surface of a planet accelerating up path of light can be bend near a planet due to "time curvature" but what about space curvature.... How does it bend the path of light?.... That is my question sir😊.....
You are doing great job! This channel is the greatest youtube discovery for me this year! But I have one problem after watching this episode and the episode in which you explained gravity according to Einstein's theory. Time dilation is causing the Earth to accelerate towards us. And here you said that acceleration is the cause why time dilates. So I don't really understand, which one is the reason of the second one and which one is the effect.
In that video, I explain why time dilation allows earth to maintain its shape even!
There are so many unaddressed realities making the notion of a ship on a surface experiencing slowed time compared to almost normal just a few hundred miles above in an orbit. Even accounting for orbital plane of the craft vs orbital plane of the planet, the planet could never exist experience such a massive shearing of time and space across its own spinning diameter. Plus the was gargantua which had a very gentle event horizon due to its massive size making it more survivable of a black hole to fall into. Assuming it even was a black hole instead of something similar and artificially created for us by future us?
The physics of Interstellar were recklessly abusive to physics and did not even try to address these enormous flaws.
Still a great movie.
So Mahesh, when spinning in your ring, the speed varies the farther out you are, but the speed is constant at the point of measurement yes? So you could argue an inertial frame of reference, unless you consider the angular momentum as an acceleration..
Speed is not changing, but the velocity is.
I can conclude that I'm a simpleton. I understood the language it was spoken in. Just no words
*PLEASE ANSWER THIS QUESTION*
If nothing can escape a blackhole so that means even information cant right??
If yes, then if there is a particle inside the event horizon of a black hole and the particle is entagled with another particle outside of a blackhole it wont able to interact or pass information to it EVEN IF WE DETECTED IT! SO DOES QUANTUM ENTANGLEMENT FAIL HERE or am i wrong?
The model using centrifugal force to describe gravity is very clever, but this model only holds true when the person holding the apple is already standing on the ground and all three body have been combined into one object beforehand, It does not explain the formation of the system. The video you described space-time curvature is what really blew my mind. Even now, I still feel it’s beyond my comprehension.
Sir please make a video on the formation of real and inverted images like how they formed on screen, what is screen, how they are inverted etc etc
A very intuitive explanation. I wait for your videos. I have an opinion and need your input if I am somewhat wrong or all out wrong.
Let's consider a graph of "speed" in a spacetime coordinate system with space in the x-axis and time in the y-axis. Does everything move at a constant speed c (speed of light) in a certain direction? If speed in space (x-axis) is close to 'c' then the time component (y-axis) will be much less. Vice-a-versa if speed in space (x-axis) is 0 then the time component (y-axis) will be maximum?
Yes.
Brilliant videos. Quick question. If you take a 3rd person reference frame, how far away from the other reference frame is required to make it a different reference frame? e.g. Cooper goes into black hole so he has his own frame and he has proper time. Can observer (observing the extreme time dilation) be right next to him and watching from say 1m away? or need to be some minimum distance away to experience that time dilation? Thanks!
Observers can be placed anywhere. To observe Cooper inside a black hole requires the observer of Coop also be in the black hole.
@@kylelochlann5053 OK thanks. So observer outside black hole could be a light year away or 1m away from Cooper and observing him about to enter the black hole - both would see him essentially freeze as time stops? Just trying to get my head around Cooper experiencing normal time and an observer right next to him watching him completely frozen! This stuff all beautifully mind blowing...
@@petercossey2723The distance in space between the observers does actually matter in this case of extreme gravitational curvature. In "flat" spacetime far away from any large mass, everywhere is kinda the same. Near a black hole however very small details and differences matters a lot more in how you transform between coordinate systems. (By "coordinate systems" I mean time and space, you know?)
@@petercossey2723 No, nothing stops or freezes, or even appears to. All observers see Coop redshift and vanish. The redshift which is a stretching out of all signals from Coop will be seen as a "slowing down". But this is short-lived, an e-fold drop in luminosity and frequency happening on the order of a few microseconds per solar mass of black hole (there is an explicit calculation in MTW, around page 850 or so, which is freely available online).
Awesome video enjoyed every bit of it :)
The problem with the apple falling in your example is the human was inverted to stand on the inside of the earth. If it was a direct comparison to how we sit on the earth… the apple actually falls away from the planet.
In previous video u said that nothing cannot enter black hole in external absorbers frame the according to an external absorber black hole dose not even exist first blace because nothing as entered the black hole is it sir?? please replay me thank u for the time
I have only one question for you: Are you the voice behind those Kahn Academy videos about ciclotrons? Because those are also awesome and the way the narrator speaks, his maneirisms are very similar to yours.
Yup :)
@@Mahesh_Shenoy Glad to know 😊
Bro I left engineering for physics but I am amazed how you have lernt so much physics even being an engineering graduate 😊❤
16:45 the gravitational field decreases below the surface and is zero at the center. If you assume a uniform density, then the decrease is linear. So the centrifuge model is not that differnt, just the direction is reversed.
and since earth's surface is covered in oceans, the real gravitational field is actually highest a few kilometers below the surface.
Yeah, it's the "Shell model", and Isaac Newton himself figured out that your weight will decrease as you go deeper and deeper into the Earth's crust. Eventually at the Earth's center of mass you would be weightless. And, this has been experimentally verified in caves and well shafts. The core of the Earth feels weightless and in an inertial orbit around the Sun. It is at a million atmosphere of pressure of course, from the 3000 miles of compressed rock and metal above it. That's the pressure you feel as 9.8m/s² of acceleration at the Earth's rocky surface.
Very Good intuition. As far as I know centripetal acceleration is another effect different and independent from space-time curvature. In fact we experience both phenomena here on Earth surface and each contribute (oppositely) to the ''gravity pull'' we feel. Nevertheless, the ''time dilation''' effects adds up. When you explain the different time dilation for different observers on a rotating space station from a ''special relativity frame'', for an outside observer, I thought that for relative time dilation to ''occur'' (and length contraction), the motion has to be in the direction of the observer, not sideways. I may be wrong tough
Regarding the Model Discussed around 15:55, what would have happened if the gravitational force near the centre were more significant? In a case where there's a disc kept at a certain distance from a sphere horizontally, the centre of the disc is aligned with the centre of the sphere. In this case, even though an observer at the centre would see that the observer near the edge has a clock ticking at a slower rate, how can we possibly explain the slowing down of his clock due to gravity as compared to the slowing down of the clock of the observer near the edge, as the clock at the centre should tick slower than the clock near edge due to high gravitational field?
This model of time dilation (at around 11.00) has always been confusing me because it only works with the "photon" in the photon clock moving transverse to velocity direction of the cart. But according to SR time dilation should not depend on the position of the clock relative to the motion direction of reference frame.
Think of a light clock as half an interferometer (because it is). And also you don't need point like "photons" this still works, even better, with the spherical surface of a wavefront propagating from the point where it reflects from the mirror.
And then you can can also use a spherical mirror, and shrink it down to microscopic size, and put trillions of them together... and you have a bunch of atoms in a "solid object".
I dont usually comment, but thats incredibly helpful!!!! Mahesh cheers from Brazil!
Another Banger, but I am concerned that you're perpetuating a grave misconception: that time dilation between two locations depends on the difference in their local gravity field strengths...which is a natural conclusion from the rotating wheel "model" (it's not a model: it is real gravity, but an analysis gets into Ehrenfest's Paradox, which is hole nother video). Bear with me:
Where in Earth does time run slowest? Dead Sea?, Challenger Deep? The Kola Super-Deep bore hole?
No: THE CENTER! (iirc, it has accumulated a 2.5 year lag since "The Beginning").
OK: what is the local gravity at the center of the earth: ZERO, ofc, by symmetry, shell th'm, etc etc.
Time dilation between two points depends on the difference in the gravitational potential energy between the two points, and is not related to the local field strength, which leads to a fun fact:
with Newton's kinetic energy KE = 1/2 m v^2
and Newton's potential energy PE = GM/r
time dilation is: gamma = 1/sqrt(1 - 2E/c^2).
with KE (PE) for relative motion (gravitational potential).
with the formulae diverging at v=c and the Schwarzschild radius, respectively.
Don't trust me bro, Trust Albert!
Yes, you are right! I'll address this in the pinned comment.
Time dilates slowly at the centre than on the surface? But how?
@@Mahesh_Shenoy* Ek X Banda h voh earth se 9000 light years dur h ...
* Uske waha gravity Kam h
* Humaare yaha zaada
* Humare yaha usko 9000 saal baad dekhenge toh woh ...
* 6-7 hr jeeke ...
* Par uski aging fast hogi ....
* kya yeh theory sahi h ?
@@theknown1741 image the frequency of a photon (or a neutrino, if the shielding bothers you) as it leaves the center of the Earth. Is it fighting gravity and losing energy (frequency) the whole way up and off into space, or does it fall from the center up to the surface, and then start its energy-losing climb?
The gravity at the center is not zero. Recall that it takes 20 numbers to specify the gravity at a spacetime point.
The Newtonian gravitational field strength is zero at the center.
Plz do make a video on River model of General Relativity, where scienceclic says that Earth do expand due to its Internal Core pressure....I understand there are different ways to explain the same question...but it clearly contradicts your explanation...specifically, The Earth Expanding Part
It's more precise to say that the Earth is _compressed_ and what you feel as a human is resistance to compressing whatever you're standing on. If your body was dense enough you could sink into rock, cement, and metal just like you can sink into snow or mud. (Skyscrapers need a special foundation to avoid sinking into the ground, for example.)
When you have a latex balloon full of air, and you squeeze it between your hands, the balloon pushes back against your hands. It's the same as with the Earth. (The latex of the baloon being gravity in this analogy.) The air in the baloon is accelerating your hands outwards.
You are now my favorite human. Brilliant explanation. Great video.
I find that the rotating spaceship model is very helpful with the occupants undergoing different amounts of angular acceleration so they each experience an accelerating frame of reference. Einstein says that you cannot distinguish between acceleration due to gravity from any other accelerating frame of reference that was his insight and it took until 1919 to show he was right
When you said that it's indistinguishable between acceleration of gravity and acceleration of any other type. Actually this holds true for only point masses. Because if you take a solid object, or even a planar object, the gravitational gradient would vary at different points of spatial coordinates of that object if it were not to be zero-dimensional. So hence that statement is not completely correct. Indeed, a person standing on Earth experiencing the g-force of 9.8 at his feet would weigh slightly less compared to a person who's accelerating at 9.8 meters per second inside a spaceship through deep space without any other forces acting on him. And it's again different compared to if a person is standing on the surface facing inwards inside a centrifuge that is rotating.
@@shrivatsa8604 Fair enough
No, there is no angular acceleration shown - it's radial acceleration.
@@shrivatsa8604 No, that's not right. The person standing in the spaceship will have less acceleration at their head than at their feet. A person with the same acceleration at their head and feet would get ripped apart.
Wow sir,🙏👏 in our Vedic Puranas, there is mention of time dilation. 1 second in brahmaloka is equal to millions of years on earth.
If you put two right hand rules together, you get wasted energy. Like the shoot the right hand rule down a cylinder, the field slides loosely around the cylinder in maxwell's. But what if you had much much more than maxwell's? You'd have completed energy loss b6 field rotations, you would have a tidal wave capacitor. Or a perfectly smooth capacitor, just like a neutrino or a Higgs field, a trans-nuclear plank maxwell.
Hey, does anyone know how 2 black holes are able to collide? In your last Video you explained that nothing ever enters a black hole from our perspective since time moves slower near large masses. But we have observed black holes colliding and messured gravitational waves
The space between the black holes shrinks smaller and smaller. Just like how everything else "falls down".
Here’s another way to think of how a planets mass affects space time.
Imagine you your are adrift in the ocean. As you’re adrift you approach several underwater mountains. The first ones peak isn’t too close to the surface and you don’t even notice it’s there. Each underwater mountain you approach has a peak closer to the surface and you notice accelerated flow over them, and the effect diminishes as you get away from them. Then you approach an island and the waves are ripping violently until you hit the surface. You find that no matter which direction you go, the flow of the water feels to keep moving you back in (not the island itself)
Nonsense! The first thing you said wrong is space time. Space time is a oxymoron. You obviously picked up from listening to pseudo scientist. Let us help your poor indoctrinated brain. There is no need to imagine. Time is the fabric of the universe. Time equals energy and energy equals mass times the speed of light squared; no space. Space is Science Fiction based on human imagination. Time is the reason for reality. Time is the reason for existence. for example, we experience time through our star, the sun. we are our star. there is no need to imagine. however, read more nonfiction. Dictionary. Encyclopedia. put down the pseudoscience and study astronomy. put down the pseudoscience and study linguistics. silly Human!
Ive got a question, if you take a 100 ton metal and a feather and you drop them the 100 ton metal will reach the ground first. If the ground execrates to meet the objects that are falling or whatever why would it be that the heavier item would reach the floor first if the ground would execrate towards the object?
The friction caused by the object interacting with the medium affects the object, in this case the feather and slows down it compared to the metal. In a vacuum, it would land at the same time . There is a video from Prof.Brian Cox who demonstrates that in a vacuum chamber. It also happens in a “no atmosphere scenario” or there is no medium that interferes the speed. This tested during one of the moon landing.
All objects fall at the same rate in a vacuum.
The ground is pushing the air which is pushing the feather. You need everything to stop touching the ground in any way at all.
Do your experiment on the Moon and the feather and the metal will hit the surface of the Moon at exactly the same instant.
Time itself cannot be manipulated,only energy such as light can bend. Also the same mass cannot occupy different space no matter how fast you travel. If you can travel faster than an image can travel than you can see yourself starting a journey but that ofcourse is only an image
So Mahesh, is the conclusion that gravity doesn't really affect time dilatation, the speed difference due to different positions in the gravity well is the reason for time dilatation?
Using the rotation analogy....the tengential speed is different...but the radial speed is the aame, correct? So, what is the analogue of radial speed in space-time?
finally I understood the relation between "gravety" and time delation
The photon clock shows us that time doesn't slow down, stuff slows down. We can infer from this that time isn't a real thing. It's just a word we use to measure change.
Assuming relativity, then there isn't anything that's slowing down.
Relativity requires that all identical clocks tick at the same rate, everywhere, and under all circumstances of motion and orientation.
I don't know what edition of the book you read, but the explanation is quite different. Near the blackhole the space is compressed therfore, easier to travel. It's like more km done in less.