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* 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.
@@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 / 3600 * 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!!
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.
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!
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!
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.
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.
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
@@genghiskhan9200Nope for you time will always tick at the same rate, but u will be moving slower through the time "compared" to other's at rest. That's what relative means.
So u r saying a tomato will perish quickly if its placed in merry go round instead if its placed away from it? When i as a child used merry go round in parks, i felt the world is fast forwarded but in reality its just visually moving faster. It didnt make the other kids in the park age more when i finished it. I still dont understand this time dilation concept.
I always wanted to ask this 2 question and you seems like can help me understand. 1) Why don't we use mechanical clock? which is working with same time interval without depending on reference frame. 2) What about our body clock how can it change? its biology and body is a separate system. I have lot of more doubts regarding the light and its speed I will ask after I get response to this questions first. 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.
I have a question: Lets say, Earth = 7Y Planet near black hole = 1H Black hole = BH 1. Are you assuming that 7P and 1H are revolving around a common center? And that 7P is much farther away from this common center? Aren't they supposed to be revolving independently around two different center? Which means their clocks are affected independently? 2. If you assume that 1H-BH and 7P are all rotating around a common center, which one is it: the center of the Milky Way? So earth is farther from this center compared to 1H-BH tandem? 3. If acceleration does affect clock speed, isn't it the only thing that is affected? Clock speed changes but the rate of aging stays the same? Isn't is supposed to be this way: That clock speed is independent to aging speed? That clock is just a physical device and has nothing to do with aging?
There is something called "point of reference ",and that point of reference can be anywhere,it's all about from which point of reference you are inferring or observing.
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.
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.
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!
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 ❤
Concise and impactful I rarely comment online, but this video compelled me to. Had I seen such content a decade ago, my life might have taken a different course.
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 UA-cam video is promoting misinformation. read more nonfiction. Dictionary. Encyclopedia. put down the pseudoscience and study linguistics. silly Human!
I'm trying to wrap my head around this, I understand being closer to a larger mass such as a blackhole, you physicaly slow down relative to others, being further out you're moving faster (assuming we are orbiting) what I don't understand is why there is a time difference and I realize its a real thing, proved with our GPS satelites and their clocks having to be very slightly offset. But from my perspective, if I'm seeing someone move faster, why are they physically aging ? I'm having an issue linking perspective of time and physically aging, are we saying the slower we move relative to others, the faster we move forward in time? I gotta eat some shrooms and rewatch this LOL
Lets say Earth was 100x bigger and I was able to drill down near the core (super powers) and I setup a couch, my NES, Commodore 64 and Xbox 360 and gamed for 100 years living off of hot pockets and Redline, you're saying when I finally emerge, I will be younger than the people near the surface?
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.
Really seems like it’s just our molecules wearing & tearing at faster & slower rates because we’re moving faster & therefore aging. Like how if you freeze something, it lasts a lot longer because you’ve slowed all of its molecules down vs something heating up & speeding up the process into burning or “aging”.
I thought I understood "why the clocks tick slower", but after this video, I realise I only "knew that clocks tick slower" without fully understanding why. This explanation helps me see why...
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 😊
Clocks are machines used to measure time, sometimes machines malfunction when used in unsuitable operating conditions, apparently acceleration/gravity affected a ticking clock and the clock started running slow(malfunctioned), that doesn’t mean time ifself has slowed.
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!
18:54 i think your observation is based on a hypothesis that either earth is pushing all objects around its surface with acceleration 9.8 or there is a centrifigal force from a center far away in the universe applying to all of us. Which one you are saying?
Nice analogy, but I think it's important to point out that there's an big discrepancy with what actually happens in gravity. This is that the relative time dilation is NOT determined by the relative strength of gravitational acceleration, but rather by the relative gravitational potential (acceleration is rate of change of potential). So for example as we approach the centre of Earth the gravitational acceleration drops towards zero, whereas the gravitational potential carries on reducing to its lowest value at the centre. And as a consequence the gravitational time dilation is at its maximum at the centre of Earth relative to a long way from Earth. The rotational model in fact still works, but the dilation in this case is due to rotational potential, not centripetal acceleration. It's just that in the rotational model potential and acceleration change together, whereas this is not true with gravity. And so with the Interstellar example the people near the black hole are NOT being crushed by immense gravitational acceleration. They are just in a location with extremely low gravitational potential, slowing down their time. Of course you can't feel potential directly, at least not until you climb out of the well, which takes a massive amount of propulsion energy to lift them out (not mentioned in Interstellar!).
Brian cox does a great practical explanation of this. Its not really gravity that dilates time it's movement through space time and lights constant speed regardless of reference frame. In interstellar the exoplanet is moving at high velocity because of its proximity to the black hold is that velocity not the gravity itself that creates the time dilation.
if time dilation is because light photon moving larger distance at angles, then its just that photon clock is just measuring time wrong, but real time is not dilating, right? we are just measuring it wrong with photon distances at angles.
@@dsd2002 something that is mind blowing is that every massive object in the universe is in different measurements of time due to both speed it is moving through the universe and through the gravitational field it happens to be in.
THIS. 100%. This is the exact thought I have whenever time dilation is discussed. Just because a clock is physically ticking slower doesn't mean time is passing more slowly. When the batteries in my kitchen clock start to die and the clock slows down, time isn't slowing down. A clock isn't time... it's just a tool for measuring it, and tools are affected by gravity. The same goes for aging. Time doesn't age us... multiple other factors do like nutrition, environment, stress, exercise, genetics, and yes, gravity. It's why some 60 year olds look 45, and some 45 year olds look 60. Time is a constant. It is only our perception of it that changes. A "slow" hour at work is the exact same length as a "fast" hour at play. Time itself is a dimension beyond gravity.
@@lj5190 Time itself doesn't exist, it's a derivative quality of a universe with its matter. Time is called a rate of changes, so if changes are slowing down it means time is slowing down. The speed of light is not just a limit of light, but of everything that exist including fundamental forces, so if those forces are slowing down in atoms then in chain reaction also in molecules and cells which controls aging processes, ultimately making us age slower.
This video is super fun, and I love your enthusiasm and clarity... However, I'm compelled to point out you never quite reached the "why" in your answer as was discussed at the beginning. Note your statement at 11:39 ; "but look at the people over here, omg, because they're moving so fast...", continuing at 11:59 ; "nothing mysterious over here, it's all because they have different speeds." We're now at time stamp 12:02 and THAT's where you needed to insert the "why"! So what's the why? It's the energy transfer. The energy used to move faster can no longer get used to move the clock forward. It's that simple. Your explanation of how gravity effects this balance of energy in the system the same way speed does is wonderful, but without pointing out the energy transfer, you still haven't gone past the "apple is red because it has skin with red pigment". Space-time, mass, energy... it's all the same stuff in different phase transitions. Take some of one phase and it has to go to another phase. More speed gets you less time while everyone else gets more time at their couch in front of UA-cam.
If you do the math on the Interstellar's black hole, it turns out to achieve this ratio of time dilation you need to be within 100 km of its event horizon, well within innermost stable orbit radius, so nothing except an accretion disk can even exist there, nevermind a planet.
Okay but the movies script was heavily critiqued by the world renowned theoretical physicist Kip Thorne. Nearly every part of it was heavily researched, critiqued and calculated by Kip Thorne. That said, I trust his opinion on Miller's planet being theoretically plausible more than your vague UA-cam comment.
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.
1:02 Apple is not an emmiter, it doesn't emmit any color. Instead, it absorbs all waves in visible spectrum except red, so you see reflected red color.
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!
@@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.
I constantly have the problem with this sentence: "imagine you see someone who is moving very fast". I can't imagine this "physically". Because now it's all pure "mathematic" - not "biology", not "reality". If something is moving very fast - you can't see it - because it's always "running away" from you point of view. But in your example with rotating spaceship - the object and the obesrver are "still" in relative to each others. So we see the object constantly. So it seems? But, what does it means "to see" something? That means the photon reflected from that object hit our eye, right? Only at this moment we could use word "I see it". But it takes time for photon to move from the object to our eye. So maybe, all this time dilatation is just simply an "optical illusion"? We don't see the real state of that object in THAT MOMENT - we just see "a picture" of that object, that came to us - delayed. At the time we get the picture - the object moved and he is at different "state" than we see on the picture at that moment? You should draw a path on which photon moves from object to our eye (in your rotating spaceship example).Is it straight line? Is it curved line? So right now it's just an "optical illusion", we see him "slower" because we get "delayed pictures" of his state. But it doesn't explain, why this "illusion" doesn't work when the object observe us! :) Why he don't get "delayed pictures" :) An also, it all seems like "optilac illusion" but then all stops and we call the object "hey, come to us to the center". He comes to us and then we see that he is really younger than us!? So it's no more "optical illusion" it's a biological reality! Something must happend during the time he was going back to us? Sorry. I still don't get it :) I mean I understand the consequences of 'mathematic rules' that provide that theorethical conclusions. But I CAN'T imagine this in reality.
I think comparing gravity (which is not a force) with a centripetal force (which is a force; the electromagnetic force to be exact) will only help as an intuition for what is actually happening and only muddles the water from there on out. The difference is that the centripetal force is actually accelerating the observers where as it's the space-time curvature itself that is responsible, which is definitely not an acceleration. Problem now is that we are back at the question from the beginning of this video. You should have sticked with your older explanation, which I'm glad you mentioned so that other people can learn it the proper way. 2 objects falling onto earth at different altitudes with the same initial speed will have different moving clocks although they don't accelerate; they are just moving in a straight line trough curved spacetime, meaning no acceleration and no change in their speed; and yet time dilation still happens.
Okay the explanation is cristal clear and I love it. Question from previous video for the context to the current question. - But why time gets curved by mass in the first place? Why does Earth's mass equal more time at the ground? Edit 1: I've just watched this video and I will reformulate my question: Why do accelerated frames of reference (like the ones created by masses's accelerations towards each other) create time dilation in the first place? Edit 2: And why space also expands with mass?
It’s because we move at light speed through space time. If we move faster through space there is less speed to go through time, and vice versa. Usually most of our speed is through time. But if you go very fast it reverses.
Sir I have an very complicated doubt in 16:22 mins that is Einstein tells that it is due to Gravity the time slows down but also saying it is nothing but an illusion so last time again can you tell what is Gravity and why it slows time and the g arrow why is downward not upward??? Please ❤❤
If you may allow then I would like to give the possible explanation. At the heart of it, what we perceive to be gravity is the equivalent of experiencing an accelerated frame of reference. In any case, gravity is due to the acceleration of ground towards us, due to the curvature of spacetime. It slows down time because again, it's essentially an acceleration. As per the analogy described in the video, such an acceleration, due to time dilation and special relativity, slows down time. Lastly, the g arrow in the rotating spaceship must not be confused with it being a planet or black hole. It is the analogy used to show how greater acceleration induces greater time dilation. Since the outer parts have greater velocity, they have greater acceleration. Hope it helps;)
Gravity is the ground pushing up on you more and more (ground is accelerating up -- ground is moving up and the rate at which it moves up is getting faster). Whether due to mass attraction causing more time (see his previous video that he linked) or due to a centrifuge.
So the arrows that follow Gravity, think of them as a accelerated velocity vector away from the center that linearly increases as the difference between it self and the constant velocity vector for the rest frame (I think I am near but something might have gone negative so can anyone help correct me?). But space is flowing to the center of mass as the earths expansion accelerates to meet it with a slight positive velocity? Pls help answer Adrito and correct any mistakes in any explanations!
I like that you essentially derived the underlying mechanism for WHY time ticks at different rates, essentially using photon clocks. However, I find the model much easier to understand where we are always moving through spacetime at the speed of light, so moving faster through space causes us to move slower through time, and vice-versa. Add to the curvature of space under gravity and objects not under acceleration always moving in straight lines through curved spacetime.
Great video sir! I have a question, if you have a fully charged battery in the higher gravitational field and I run wires to the lower gravitational field, will the battery last longer?
It's because of the gravity produced by the massive object that curves the path of light. By curving that path for photons to travel, it slows down the photons, whereas on a flatter grid that is not being influenced by the gravity of a massive object but rather a smaller object of less mass, the photons move faster in that straighter line due to the weaker gravitational pull of the smaller mass.
@mathura08 say that to the people who have to account for the time dilation that occurs on our man made satellites in space. They move through space a little faster relative to anything here on Earth due to gravitational time dilation and scientists have to constantly account for the small time slippage in the satellites internal clocks because if they don't, things like the GPS's you and I constantly use would be completely out of whack. So no, it's "not just a theory"...
Relativity doesn't answer my question because general relativity is just a mathematical model, derived to fit an observation(s). It can explain what is happening, but can't explain how it is happening. IMO, spacetime is the means by which everything is entangled at a quantum level. Here is another question: when a high energy photon decays into an electron and positron, what's happened to the original photon? Has it ceased to exist?
Food for thought: If gravity slows down time, and affects space-time curvature, near black holes, it's so intense that light practically stops. Why does it stop if light speed is a constant? Well, the space value of light speed remains constant, but time is slowed down to a stop. That means that inside a black hole's event horizon, time is so slow that light from the start of the universe is still there. That's why a black hole is black. Because light from it never came out, yet. So, does that mean that the black hole is really a hole, or a deformation on space-time? Or is it maybe a star similar to a neutron star, with such a massive gravity that slows time to a stop? And the measurement of distance of stars? Is it really that viable, when we know that light when near a massive star can move slower than it should? What about light coming from another galaxy? Is light's time factor moving faster in the empty space between galaxies where it's not affected by gravity? Because, time as we perceive on earth maybe very well be already very compressed, compared to the void between galaxies.
ANOTHER WAY TO LOOK AT IT: 1. To remain stationary in curved space, you need to accelerate. The stronger the curve, the more you need to accelerate to remain stationary. A hard surface does this for you. In space, you need fuel. Near a black hole, you need a LOT of fuel. 2. What this means is that, instead of you being on a rotating space station, you are stationary and curved space is passing over you, and your straight line path will curve into the gravitational source, just like the rotating model with the apple. 3. As far as light is concerned, you are the only object in the universe. It is why, no matter how 'fast' you are going, light will leave you at the speed of light. 4. Relative to others, however, your clock ticks slower (as do your cells supposedly), since light cannot keep up due to its speed limit. Everything runs slower while traveling through spacetime due to the speed limit of light. Sadly, it should be 'spacechange', since it is change that is altering, which includes clocks (time). Blame Einstein's professor for coming up with the misnomer 'spacetime'. He even confused Einstein, who did not see the error or correct his professor. 5. So now we have silly notions such as 'backwards time travel' and 'time is an illusion'. If you want to go back in time, just run your clock backwards. Time is not an illusion, it is a tool that we invented to give sequential order to different states of change. We do not even need time, just sequential numbers. Change does not need time units applied to it. It will still change regardless. CONCLUSION: You are going in a straight line, but through curved space, which acts like the outer edge of the space station. Black holes curve space a lot, so you better correct your straight line course near them or you will end up inside of them rather quickly. FUN FACT: When a star collapses into a black hole, it still has the same amount of gravity as it had when a sun (if it did not lose any mass in the process). So if the transformation happens fast enough, orbiting planets will not sense any change in gravity, and their orbits will remain the same.
I don't like that you describe gravity with the parallel to the centrifugal force. Gravity is because space moves towards mass (spacetime curvature) and the ground stops you from moving with space to the center of the planet, Star, black hole. This also means that you are moving relativ to space, not because you are moving but because space is moving and moving objects are time dilated. This is how i understand it and im pretty sure it's true.
@@CCave-wj6xy So do you expect Mahesh to alter his explanations to accommodate for every possible misinterpretation? What are you even complaining about?
17:27 That depends. If you are near a supermassive black hole, the gravitational gradient is not so extreme, so the smaller the black hole, the larger the difference between distances. Clocks will tick similar near a supermassive black hole, but will tick wildly different near a stellar mass black hole.
I absolutely LOVE the way you explore these concepts as a conversation with the physicists who elucidated them. I feel like this lays a foundation for true understanding of the processes rather than simply learning the principles and memorizing them. I’m about to complete a physics II course, likely the last of physics I’ll ever take because I’m studying biology, but I will continue to watch these videos because I think chasing a deeper understanding of our world as a whole is very valuable! Thank you!❤️
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! :-)
That may be how the math works, but one problem I have with interstellar is that Brand, Cooper, and crew needed a Saturn V rocket to leave the Earth at the start of their journey, but apparently a craft the size of a Winnebago was able to leave a more massive planet (with a deeper gravity well than Earth) and then escape Gargantua's even deeper gravity well later in the movie. I get that, "it's only a movie," but it seems inconsistent.
Fun question for everyone. 😅 If someone start digging the earth core and try to reach it's center which one happens first? 1. Get burned by the excessive heat. 2. Get crushed by the expanded air pressure. 3. Get old and die because of the time dilation.
@Mahesh, hi. I just happened to watch the video about gravity and the curvature of time first, and that video makes more sense and explains the gravitational effect better, so much so that it contradicts this one (in my opinion). Let's see. I can understand the concept of gravity being caused by centripetal force as demonstrated in this video, but this doesn't apply to our planet, because we don't walk surrounded by an external wall, on the other hand, this would mean that those living at the equator would feel the maximum attraction and those at the poles would feel its absence. Question 2: If gravity is a rotational consequence, what would happen to 2 objects with the same mass, but one rotating on its axis and the other stationary relative to its own axis? Would the gravitational force be different? In any case, the way in which the explanations are presented is really intuitive and explanatory, and makes us reason in a scientific way.
Wouldn't it be simpler just to imagine that "spacetime" to be "absorbed" (as like sucked in) by gravity. I say this because when looking at your rotating turfs I was thinking why aren't we pushed upward by the centrifugal force? Regarding the time issue, my understanding is that each spacetime block has a fixed size. This means that when the space part is contracted the time part has to be dilated and vice versa. What do you think?
Well done! I now have a good intuitive feel for time dilation with relativity. Tell Einstein thanks from me next time you talk with him! I also want to share my way of thinking about bodies moving in space time and the link to quantum mechanics. A particle, and the body comprised of a big set of particles, travels through space time by slipping from one point in space time to the next. This is done at a rate that is somehow related to the wave vibrations at the most basic level. I think of it as blinking. If the particles and the body they comprise move faster through space, then a larger component of the blinking (which the particle does as part of the essence of its existence) is used getting from one point in space to the next and less is available for getting from one point in time to the next. It helps some to think in terms one dimension of space, the one the body of particles is moving in. The trade off between moving in space and moving in time seems more symmetric. The fastest the particles can go in space is limited by the blinking rate, which is what gives rise to the speed of light limit. At that speed the particles do not experience time passing. As the speed slows, there is more blinking available for time to pass. The effect of mass is to compress things for the blinking of the particle, which bends the particle towards the mass. The compression makes the blinking occur over shorter distances and times, which pulls the particles inwards towards the mass. As far as I can tell, none of this contradicts relativity or quantum mechanics. Now, one implication of my intuitive model is that if a particle slows enough that it reaches the fastest it can go through time - that would be when the particle is effectively at rest because none of the blinking is left for going from point to point through space. It is the analog to the speed of light, what I think of as the maximum rate of time, or the resting blinking rate. Does that perhaps provide an approach to some mathematical treatment of my intuitive model and perhaps even a way to develop some sort of empirical testing?
It always helped me to understand this concept by not thinking of space and time as separate but as linked as Einstein did by describing it as spacetime. So if they are connected then changing the speed you are traveling through one should always change the speed you are traveling through the other. Gravity and acceleration are just a means to change the speed you are traveling through spacetime.
The speed of light isn't a constant; it's more likely that it's the amount of time it takes for a given area of space to process all the things that need to happen. A black hole isn't an infinite dense point in space, it's a powerful energy conversion machine. With more matter/energy you have slower time, which is effectively the frame rate of the universe. The reason light can't escape it isn't due to gravity, it's due to the way energy currents function in space. These energy currents hold the galaxy together, but if there is more energy than can be converted and sent into the galaxy, you'll get a pulsar, which is the method it uses to dump energy. These would be equal to the auroras on the planets. Hope this helps! edit: Aging slower is just a matter of each frame taking longer to process. Going fast means more processing per frame. It's a lot simpler than this mathematical model being described.
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.
Brilliant is exactly the right word to describe you. That explanation was so clear and to the point. Please keep making videos like these they are marvelous.
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.
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
This is by far the video of the millennium to me.. for someone who studied physics during non youtube times..👍 Pls continue to make these videos .....dont stop.
First thing that's wrong with that scene in interstellar, is that the planet is within that light ring around the black hole. The gravity is so great that it traps the light into a "ring". That LIGHT RING around the black hole is going to lie well within the Roche limit. Planets can't exist there, because the immense gravitational forces would rip them apart.
WRT the person at the center of the spaceship, the person at the far end isn't moving and remains at rest (assuming both are standing). If their relative velocity is the same but their time flows differently due to varying acceleration and increased gravity, it would be strange. The person at the center would see the one at the far end waving their hand in slow motion... your explanation just made another of reason of time dilation more clear to me!
@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 ).
I discovered this channel and oh my i am just binge watching every video. Your explanation are brilliant. Better then veritasiums explanation. Keep going 🏆
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😊.....
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.
OK. @5:11, it talked about the ground accelerated to meet the apple & not the apple falling down. So, the next time when you are accused of landing a devastating punch on someone face, you can defend your act by claiming you did not punch someone face mightily. It was the other person's face accelerating at a stupefied rate toward your fist. That is your scientific get out of jail explanation.
This is a good explanation but i already had a decent understanding that time is dilated by gravity due to proximity 😂😂 However, this was extremely handy. Being able to explain a concept is a tough task. Thanks for taking the effort to make Einstein's explanation simple enough to understand easily
I hate ads in the middle of videos, but I get that it lets you have a source of income without having the ad interruptions all throughout the video. I do have to say that transition into the ad was pure comedy though. Made me giggle pretty strongly.
Hi, and what about moving faster? If we have strong gravity/acceleration time ticks slower. But if you move fast without any acceleration you won't feel and gravity/force but you still should age slower than someone who is not. What's the difference?
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
Ok. Here's the problem though: How can black holes come into existence, given the time dilation around them? Let's first examine an object falling into the black hole. As the object gets closer, time slows down for it AS PERCEIVED FROM AN OUTSIDE OBSERVER. That means, for the observer, the object's fall towards the black hole gets slower and slower. From the perspective of someone inside the falling object, and looking back out, time in the rest of the universe speeds up more and more: So decades pass in mere minutes. Ok, now: As I understand it, by the time the object reaches the event horizon, its clock slows to zero (or the outside clocks speed up to infinity). What that must mean though for an outside observer is that the object comes to a virtual standstill before it can ever reach the event horizon. From the perspective of the object, on the other hand, they see the complete history of the universe pass on the outside (even if the universe was eternal) BEFORE they enter the event horizon. So: That means that for the outside observer (for example someone on earth) NOTHING can EVER fall into the black hole completely (during our lifetime, the lifetime of the earth, or even the lifetime of the universe). Instead, all objects approaching the black hole, appear frozen in time and space at some distance from the event horizon. --If this is not so, it would be great if someone could point out where my logic fails me here. Ok, now let's take this further and look at how the black hole comes into existence in the first place: A massive star is collapsing on itself and the matter at its center is getting more and more dense, as the gravity it “produces” gets stronger and stronger. But that means that time at the center of the collapsing star starts to slow down more and more, which means that-again for the outside observer-this collapse itself should appear to happen more and more slowly. As the star gets closer and closer to becoming a black hole and forming an event horizon, this time dilation, again, should become so extreme that it slows time down to almost-and eventually exactly-zero, before that matter can ever become dense enough to form a black hole. Again, not from the perspective of the collapsing star itself, but from the perspective of the entire universe surrounding it. But that means, that it is not possible for a black hole to actually finish its process of formation during the lifetime of the Universe. I am not confused here: I know that from the perspective of the collapsing star there is no problem: It simply keeps collapsing, and may even do so faster and faster-but just like for the object falling into the black hole, from the perspective of the collapsing star, the time in universe around it goes faster and faster and the star would “see” the entire eternal history of the universe pass, by the time it becomes an actual black hole. Again, from the outside perspective, the collapse of the star should slow down more and more, so much so, that it will appear frozen, before it ever becomes a black hole. So: how can black holes ever form within the lifetime of the universe? They could still exist, but they would have had to have been there from the very beginning. They could not have formed at any point thereafter. where am I missing something? One point I am not 100% certain of is, if the event horizon actually represents the point where time slows to zero-since it is the point where light cannot escape, it seems to me that it is the point where time would also slow to zero, but even if it is not, there would still have to be such a point somewhere deep in the black hole, where the boundary of the singularity exists-so I am not convinced that this even makes a difference. I know, chances that you will actually read this comment are minuscule at this point, but a video on explaining why black holes can form in a region of space where clocks move at zero speed compared to the outside universe, would be really awesome! Cheers! Love your explanations!
This one gets me the speed of light is constant for all observers... time dilation means seconds pass differently so light has to slow down in gravitational field in order to match time dilation so that speed remains the same. And vice versa.
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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.
Thank you
Never stop making videos even if u get less views,some channels r really good and this is one of it
Fewer views...
TO EVERYONE IN THIS CHAT:
*THE JUDGEMENT OF GOD IS DRAWING NIGH.*
REPENT TODAY AND GIVE YOUR LIFE TO JESUS TO ESCAPE ETERNAL DAMNATION!,..
@@JesusPlsSaveMe 😆
@@JesusPlsSaveMeWow I became christian after reading your comment
Life's uncertainties 😂
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 / 3600 * 220752000 = 70947240
70947240 seconds = 2.25 years
@@wlockuz4467maybe you are Millerian. Your math is impeccable.
@@wlockuz4467 awhhhhh I see I see
TO EVERYONE IN THIS CHAT:
*THE JUDGEMENT OF GOD IS DRAWING NIGH.*
REPENT TODAY AND GIVE YOUR LIFE TO JESUS TO ESCAPE ETERNAL DAMNATION!,..
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!!
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.
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!
Watch closely there are cuts and he is looking towards the side most probably at his notes, still it's good video
He has ads for brilliant, that's a break. Anytime there is an animation is a break.
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 😭
I am really close to a brown hole within 3 feet and I am still getting older
@@JusticeLeGrand10101 Aren't you the genius huh?
Listen to me, you sir are the best UA-camr, period. Please never stop making videos
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.
Science Clic English is really good too
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 😁
@@genghiskhan9200Nope for you time will always tick at the same rate, but u will be moving slower through the time "compared" to other's at rest. That's what relative means.
My question is, why would you think a planet so close to a black hole that time is slowed down 1000x might be inhabitable?
Because you want to spite the other scientist on your team who you think is being emotional.
@@CheeseDanish85that was for the other planet.
the gravity will crush you
@@अपना_रोहित “I WILL CRUSH YOU!”
But supposing that the gravity is tolerable, humans will live longer than on earth
So u r saying a tomato will perish quickly if its placed in merry go round instead if its placed away from it?
When i as a child used merry go round in parks, i felt the world is fast forwarded but in reality its just visually moving faster. It didnt make the other kids in the park age more when i finished it.
I still dont understand this time dilation concept.
I always wanted to ask this 2 question and you seems like can help me understand. 1) Why don't we use mechanical clock? which is working with same time interval without depending on reference frame. 2) What about our body clock how can it change? its biology and body is a separate system. I have lot of more doubts regarding the light and its speed I will ask after I get response to this questions first. 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.
I have a question:
Lets say,
Earth = 7Y
Planet near black hole = 1H
Black hole = BH
1. Are you assuming that 7P and 1H are revolving around a common center? And that 7P is much farther away from this common center? Aren't they supposed to be revolving independently around two different center? Which means their clocks are affected independently?
2. If you assume that 1H-BH and 7P are all rotating around a common center, which one is it: the center of the Milky Way? So earth is farther from this center compared to 1H-BH tandem?
3. If acceleration does affect clock speed, isn't it the only thing that is affected? Clock speed changes but the rate of aging stays the same? Isn't is supposed to be this way:
That clock speed is independent to aging speed? That clock is just a physical device and has nothing to do with aging?
There is something called "point of reference ",and that point of reference can be anywhere,it's all about from which point of reference you are inferring or observing.
he is a gem to the world we need to protect it!!!💖💖
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.
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.
I am really close to a brown hole within 3 feet and I am still getting older
Without motion there is no time*
Age dilation isn’t real only time dilation. Aka the clock count
@@Peoplearedumb47 But without motion, why so much commotion? Conjunction, junction what's your function?
@@alexshatner3907 and?
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!
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 ❤
Concise and impactful
I rarely comment online, but this video compelled me to. Had I seen such content a decade ago, my life might have taken a different course.
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 UA-cam video is promoting misinformation. read more nonfiction. Dictionary. Encyclopedia. put down the pseudoscience and study linguistics. silly Human!
I'm trying to wrap my head around this, I understand being closer to a larger mass such as a blackhole, you physicaly slow down relative to others, being further out you're moving faster (assuming we are orbiting) what I don't understand is why there is a time difference and I realize its a real thing, proved with our GPS satelites and their clocks having to be very slightly offset. But from my perspective, if I'm seeing someone move faster, why are they physically aging ? I'm having an issue linking perspective of time and physically aging, are we saying the slower we move relative to others, the faster we move forward in time? I gotta eat some shrooms and rewatch this LOL
Lets say Earth was 100x bigger and I was able to drill down near the core (super powers) and I setup a couch, my NES, Commodore 64 and Xbox 360 and gamed for 100 years living off of hot pockets and Redline, you're saying when I finally emerge, I will be younger than the people near the surface?
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 👍🏻
Really seems like it’s just our molecules wearing & tearing at faster & slower rates because we’re moving faster & therefore aging. Like how if you freeze something, it lasts a lot longer because you’ve slowed all of its molecules down vs something heating up & speeding up the process into burning or “aging”.
I think Einstein would be proud of you.
I thought I understood "why the clocks tick slower", but after this video, I realise I only "knew that clocks tick slower" without fully understanding why. This explanation helps me see why...
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 😊
Clocks are machines used to measure time, sometimes machines malfunction when used in unsuitable operating conditions, apparently acceleration/gravity affected a ticking clock and the clock started running slow(malfunctioned), that doesn’t mean time ifself has slowed.
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!
If it will make you feel any better, You're not alone, and I'm a physics teacher😂
18:54 i think your observation is based on a hypothesis that either earth is pushing all objects around its surface with acceleration 9.8 or there is a centrifigal force from a center far away in the universe applying to all of us. Which one you are saying?
Having an instructor that truly want the pupil to understand the subject makes all the difference.
Nice analogy, but I think it's important to point out that there's an big discrepancy with what actually happens in gravity. This is that the relative time dilation is NOT determined by the relative strength of gravitational acceleration, but rather by the relative gravitational potential (acceleration is rate of change of potential). So for example as we approach the centre of Earth the gravitational acceleration drops towards zero, whereas the gravitational potential carries on reducing to its lowest value at the centre. And as a consequence the gravitational time dilation is at its maximum at the centre of Earth relative to a long way from Earth. The rotational model in fact still works, but the dilation in this case is due to rotational potential, not centripetal acceleration. It's just that in the rotational model potential and acceleration change together, whereas this is not true with gravity. And so with the Interstellar example the people near the black hole are NOT being crushed by immense gravitational acceleration. They are just in a location with extremely low gravitational potential, slowing down their time. Of course you can't feel potential directly, at least not until you climb out of the well, which takes a massive amount of propulsion energy to lift them out (not mentioned in Interstellar!).
Mind blowing animation sir
Brian cox does a great practical explanation of this. Its not really gravity that dilates time it's movement through space time and lights constant speed regardless of reference frame. In interstellar the exoplanet is moving at high velocity because of its proximity to the black hold is that velocity not the gravity itself that creates the time dilation.
if time dilation is because light photon moving larger distance at angles, then its just that photon clock is just measuring time wrong, but real time is not dilating, right? we are just measuring it wrong with photon distances at angles.
@@dsd2002 something that is mind blowing is that every massive object in the universe is in different measurements of time due to both speed it is moving through the universe and through the gravitational field it happens to be in.
THIS. 100%. This is the exact thought I have whenever time dilation is discussed.
Just because a clock is physically ticking slower doesn't mean time is passing more slowly. When the batteries in my kitchen clock start to die and the clock slows down, time isn't slowing down. A clock isn't time... it's just a tool for measuring it, and tools are affected by gravity.
The same goes for aging. Time doesn't age us... multiple other factors do like nutrition, environment, stress, exercise, genetics, and yes, gravity. It's why some 60 year olds look 45, and some 45 year olds look 60.
Time is a constant. It is only our perception of it that changes. A "slow" hour at work is the exact same length as a "fast" hour at play.
Time itself is a dimension beyond gravity.
it is measured by decay... atomic clock...not by dial clocks
@@lj5190 Time itself doesn't exist, it's a derivative quality of a universe with its matter. Time is called a rate of changes, so if changes are slowing down it means time is slowing down. The speed of light is not just a limit of light, but of everything that exist including fundamental forces, so if those forces are slowing down in atoms then in chain reaction also in molecules and cells which controls aging processes, ultimately making us age slower.
@@Bleacher22 Time and rate of change are two different things.
This video is super fun, and I love your enthusiasm and clarity... However, I'm compelled to point out you never quite reached the "why" in your answer as was discussed at the beginning. Note your statement at 11:39 ; "but look at the people over here, omg, because they're moving so fast...", continuing at 11:59 ; "nothing mysterious over here, it's all because they have different speeds." We're now at time stamp 12:02 and THAT's where you needed to insert the "why"! So what's the why? It's the energy transfer. The energy used to move faster can no longer get used to move the clock forward. It's that simple. Your explanation of how gravity effects this balance of energy in the system the same way speed does is wonderful, but without pointing out the energy transfer, you still haven't gone past the "apple is red because it has skin with red pigment". Space-time, mass, energy... it's all the same stuff in different phase transitions. Take some of one phase and it has to go to another phase. More speed gets you less time while everyone else gets more time at their couch in front of UA-cam.
If you do the math on the Interstellar's black hole, it turns out to achieve this ratio of time dilation you need to be within 100 km of its event horizon, well within innermost stable orbit radius, so nothing except an accretion disk can even exist there, nevermind a planet.
Okay but the movies script was heavily critiqued by the world renowned theoretical physicist Kip Thorne. Nearly every part of it was heavily researched, critiqued and calculated by Kip Thorne. That said, I trust his opinion on Miller's planet being theoretically plausible more than your vague UA-cam comment.
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.
Your visual representation is wrong. The two land surface should be outward and the force that pull in is centripetal
I also thought about that
Can you prove it and make a video , dont just give bullshit opinion
This was the explanation Einstein gave in the book…So let me get this straight, you’re implying that you’re smarter than Albert Einstein?
@@NoubelShimulyou bullshit. What a thing to say
@@NoubelShimulyou bullshit. What a thing to say
1:02 Apple is not an emmiter, it doesn't emmit any color. Instead, it absorbs all waves in visible spectrum except red, so you see reflected red color.
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.
Please don’t stop making videos, You cure depression.
This is amazing intuition into a very hard problem. Great job
I constantly have the problem with this sentence: "imagine you see someone who is moving very fast".
I can't imagine this "physically". Because now it's all pure "mathematic" - not "biology", not "reality".
If something is moving very fast - you can't see it - because it's always "running away" from you point of view.
But in your example with rotating spaceship - the object and the obesrver are "still" in relative to each others. So we see the object constantly. So it seems?
But, what does it means "to see" something? That means the photon reflected from that object hit our eye, right? Only at this moment we could use word "I see it".
But it takes time for photon to move from the object to our eye.
So maybe, all this time dilatation is just simply an "optical illusion"? We don't see the real state of that object in THAT MOMENT - we just see "a picture" of that object, that came to us - delayed. At the time we get the picture - the object moved and he is at different "state" than we see on the picture at that moment?
You should draw a path on which photon moves from object to our eye (in your rotating spaceship example).Is it straight line? Is it curved line?
So right now it's just an "optical illusion", we see him "slower" because we get "delayed pictures" of his state.
But it doesn't explain, why this "illusion" doesn't work when the object observe us! :) Why he don't get "delayed pictures" :)
An also, it all seems like "optilac illusion" but then all stops and we call the object "hey, come to us to the center". He comes to us and then we see that he is really younger than us!? So it's no more "optical illusion" it's a biological reality!
Something must happend during the time he was going back to us?
Sorry. I still don't get it :)
I mean I understand the consequences of 'mathematic rules' that provide that theorethical conclusions.
But I CAN'T imagine this in reality.
I think comparing gravity (which is not a force) with a centripetal force (which is a force; the electromagnetic force to be exact) will only help as an intuition for what is actually happening and only muddles the water from there on out. The difference is that the centripetal force is actually accelerating the observers where as it's the space-time curvature itself that is responsible, which is definitely not an acceleration. Problem now is that we are back at the question from the beginning of this video. You should have sticked with your older explanation, which I'm glad you mentioned so that other people can learn it the proper way.
2 objects falling onto earth at different altitudes with the same initial speed will have different moving clocks although they don't accelerate; they are just moving in a straight line trough curved spacetime, meaning no acceleration and no change in their speed; and yet time dilation still happens.
Okay the explanation is cristal clear and I love it. Question from previous video for the context to the current question.
- But why time gets curved by mass in the first place? Why does Earth's mass equal more time at the ground?
Edit 1: I've just watched this video and I will reformulate my question: Why do accelerated frames of reference (like the ones created by masses's accelerations towards each other) create time dilation in the first place?
Edit 2: And why space also expands with mass?
It’s because we move at light speed through space time. If we move faster through space there is less speed to go through time, and vice versa. Usually most of our speed is through time. But if you go very fast it reverses.
Amazing content as always!
You are a brilliant instructor. The world is a better place because of you.
Sir I have an very complicated doubt in 16:22 mins that is Einstein tells that it is due to Gravity the time slows down but also saying it is nothing but an illusion so last time again can you tell what is Gravity and why it slows time and the g arrow why is downward not upward??? Please ❤❤
g is down because if you drop something, it falls down.
If you may allow then I would like to give the possible explanation. At the heart of it, what we perceive to be gravity is the equivalent of experiencing an accelerated frame of reference. In any case, gravity is due to the acceleration of ground towards us, due to the curvature of spacetime.
It slows down time because again, it's essentially an acceleration. As per the analogy described in the video, such an acceleration, due to time dilation and special relativity, slows down time.
Lastly, the g arrow in the rotating spaceship must not be confused with it being a planet or black hole. It is the analogy used to show how greater acceleration induces greater time dilation. Since the outer parts have greater velocity, they have greater acceleration.
Hope it helps;)
Gravity is the ground pushing up on you more and more (ground is accelerating up -- ground is moving up and the rate at which it moves up is getting faster). Whether due to mass attraction causing more time (see his previous video that he linked) or due to a centrifuge.
So the arrows that follow Gravity, think of them as a accelerated velocity vector away from the center that linearly increases as the difference between it self and the constant velocity vector for the rest frame (I think I am near but something might have gone negative so can anyone help correct me?). But space is flowing to the center of mass as the earths expansion accelerates to meet it with a slight positive velocity? Pls help answer Adrito and correct any mistakes in any explanations!
@@varunvaswani4562 No, that's no right at all. Time dilation has nothing, per se, to do with acceleration.
I like that you essentially derived the underlying mechanism for WHY time ticks at different rates, essentially using photon clocks. However, I find the model much easier to understand where we are always moving through spacetime at the speed of light, so moving faster through space causes us to move slower through time, and vice-versa. Add to the curvature of space under gravity and objects not under acceleration always moving in straight lines through curved spacetime.
Thank you. You are an amazing teacher.
Great video sir! I have a question, if you have a fully charged battery in the higher gravitational field and I run wires to the lower gravitational field, will the battery last longer?
Why does mass cause spacetime to be curved?
Space curvature is just theory, it's just assumption
We really don't know how gravity works practically
If time is really higher dimensional thing then
I think we can't really explain how it works practically
It's because of the gravity produced by the massive object that curves the path of light. By curving that path for photons to travel, it slows down the photons, whereas on a flatter grid that is not being influenced by the gravity of a massive object but rather a smaller object of less mass, the photons move faster in that straighter line due to the weaker gravitational pull of the smaller mass.
@mathura08 say that to the people who have to account for the time dilation that occurs on our man made satellites in space. They move through space a little faster relative to anything here on Earth due to gravitational time dilation and scientists have to constantly account for the small time slippage in the satellites internal clocks because if they don't, things like the GPS's you and I constantly use would be completely out of whack. So no, it's "not just a theory"...
Relativity doesn't answer my question because general relativity is just a mathematical model, derived to fit an observation(s). It can explain what is happening, but can't explain how it is happening. IMO, spacetime is the means by which everything is entangled at a quantum level. Here is another question: when a high energy photon decays into an electron and positron, what's happened to the original photon? Has it ceased to exist?
Food for thought:
If gravity slows down time, and affects space-time curvature, near black holes, it's so intense that light practically stops. Why does it stop if light speed is a constant? Well, the space value of light speed remains constant, but time is slowed down to a stop. That means that inside a black hole's event horizon, time is so slow that light from the start of the universe is still there. That's why a black hole is black. Because light from it never came out, yet.
So, does that mean that the black hole is really a hole, or a deformation on space-time? Or is it maybe a star similar to a neutron star, with such a massive gravity that slows time to a stop?
And the measurement of distance of stars? Is it really that viable, when we know that light when near a massive star can move slower than it should?
What about light coming from another galaxy? Is light's time factor moving faster in the empty space between galaxies where it's not affected by gravity? Because, time as we perceive on earth maybe very well be already very compressed, compared to the void between galaxies.
But this explanation goes opposite to the fact that a guy in space would age slower than a guy on earth.
That's time dilation due to orbit speed, this is time dilation due to gravity
Man !!! I look forward to going over your other videos your enthusiasm is absolutely contagious!!!
bro i looooooooooveeeeeeeeeeeee your videos. they are soo awesome and on top of that they teach me sooo much. i hope you heart my comment😁
ANOTHER WAY TO LOOK AT IT:
1. To remain stationary in curved space, you need to accelerate. The stronger the curve, the more you need to accelerate to remain stationary. A hard surface does this for you. In space, you need fuel. Near a black hole, you need a LOT of fuel.
2. What this means is that, instead of you being on a rotating space station, you are stationary and curved space is passing over you, and your straight line path will curve into the gravitational source, just like the rotating model with the apple.
3. As far as light is concerned, you are the only object in the universe. It is why, no matter how 'fast' you are going, light will leave you at the speed of light.
4. Relative to others, however, your clock ticks slower (as do your cells supposedly), since light cannot keep up due to its speed limit. Everything runs slower while traveling through spacetime due to the speed limit of light. Sadly, it should be 'spacechange', since it is change that is altering, which includes clocks (time). Blame Einstein's professor for coming up with the misnomer 'spacetime'. He even confused Einstein, who did not see the error or correct his professor.
5. So now we have silly notions such as 'backwards time travel' and 'time is an illusion'. If you want to go back in time, just run your clock backwards. Time is not an illusion, it is a tool that we invented to give sequential order to different states of change. We do not even need time, just sequential numbers. Change does not need time units applied to it. It will still change regardless.
CONCLUSION:
You are going in a straight line, but through curved space, which acts like the outer edge of the space station. Black holes curve space a lot, so you better correct your straight line course near them or you will end up inside of them rather quickly.
FUN FACT:
When a star collapses into a black hole, it still has the same amount of gravity as it had when a sun (if it did not lose any mass in the process). So if the transformation happens fast enough, orbiting planets will not sense any change in gravity, and their orbits will remain the same.
I don't like that you describe gravity with the parallel to the centrifugal force.
Gravity is because space moves towards mass (spacetime curvature) and the ground stops you from moving with space to the center of the planet, Star, black hole.
This also means that you are moving relativ to space, not because you are moving but because space is moving and moving objects are time dilated.
This is how i understand it and im pretty sure it's true.
Congratulations, you have just convinced people that the rotation of the Earth causes gravity.
He clearly said the opposite at the start.
@@logicianbones But that is not the part people will remember.
@@ShawnHCoreyNot his problem that stupid people exist.
What an absurd comment
@@CCave-wj6xy So do you expect Mahesh to alter his explanations to accommodate for every possible misinterpretation? What are you even complaining about?
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. ❤
Early comments give more likes...😊😊😊
17:27 That depends. If you are near a supermassive black hole, the gravitational gradient is not so extreme, so the smaller the black hole, the larger the difference between distances. Clocks will tick similar near a supermassive black hole, but will tick wildly different near a stellar mass black hole.
I absolutely LOVE the way you explore these concepts as a conversation with the physicists who elucidated them. I feel like this lays a foundation for true understanding of the processes rather than simply learning the principles and memorizing them.
I’m about to complete a physics II course, likely the last of physics I’ll ever take because I’m studying biology, but I will continue to watch these videos because I think chasing a deeper understanding of our world as a whole is very valuable! Thank you!❤️
Bruh... That ad transition was straight up devious... Bravo... Bravo
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! :-)
For everyone local time is normal, universal limit of speed is speed of light it means for signals and travels.
That may be how the math works, but one problem I have with interstellar is that Brand, Cooper, and crew needed a Saturn V rocket to leave the Earth at the start of their journey, but apparently a craft the size of a Winnebago was able to leave a more massive planet (with a deeper gravity well than Earth) and then escape Gargantua's even deeper gravity well later in the movie. I get that, "it's only a movie," but it seems inconsistent.
Fun question for everyone. 😅
If someone start digging the earth core and try to reach it's center which one happens first?
1. Get burned by the excessive heat.
2. Get crushed by the expanded air pressure.
3. Get old and die because of the time dilation.
@Mahesh, hi. I just happened to watch the video about gravity and the curvature of time first, and that video makes more sense and explains the gravitational effect better, so much so that it contradicts this one (in my opinion). Let's see. I can understand the concept of gravity being caused by centripetal force as demonstrated in this video, but this doesn't apply to our planet, because we don't walk surrounded by an external wall, on the other hand, this would mean that those living at the equator would feel the maximum attraction and those at the poles would feel its absence.
Question 2: If gravity is a rotational consequence, what would happen to 2 objects with the same mass, but one rotating on its axis and the other stationary relative to its own axis? Would the gravitational force be different?
In any case, the way in which the explanations are presented is really intuitive and explanatory, and makes us reason in a scientific way.
I may have already wrote it but you’re as good as 3blur1btown yet in a totally different way when it comes to pedagogy. Bravo monsieur !
Wouldn't it be simpler just to imagine that "spacetime" to be "absorbed" (as like sucked in) by gravity. I say this because when looking at your rotating turfs I was thinking why aren't we pushed upward by the centrifugal force?
Regarding the time issue, my understanding is that each spacetime block has a fixed size. This means that when the space part is contracted the time part has to be dilated and vice versa.
What do you think?
Well done! I now have a good intuitive feel for time dilation with relativity. Tell Einstein thanks from me next time you talk with him!
I also want to share my way of thinking about bodies moving in space time and the link to quantum mechanics. A particle, and the body comprised of a big set of particles, travels through space time by slipping from one point in space time to the next. This is done at a rate that is somehow related to the wave vibrations at the most basic level. I think of it as blinking. If the particles and the body they comprise move faster through space, then a larger component of the blinking (which the particle does as part of the essence of its existence) is used getting from one point in space to the next and less is available for getting from one point in time to the next. It helps some to think in terms one dimension of space, the one the body of particles is moving in. The trade off between moving in space and moving in time seems more symmetric. The fastest the particles can go in space is limited by the blinking rate, which is what gives rise to the speed of light limit. At that speed the particles do not experience time passing. As the speed slows, there is more blinking available for time to pass. The effect of mass is to compress things for the blinking of the particle, which bends the particle towards the mass. The compression makes the blinking occur over shorter distances and times, which pulls the particles inwards towards the mass.
As far as I can tell, none of this contradicts relativity or quantum mechanics.
Now, one implication of my intuitive model is that if a particle slows enough that it reaches the fastest it can go through time - that would be when the particle is effectively at rest because none of the blinking is left for going from point to point through space. It is the analog to the speed of light, what I think of as the maximum rate of time, or the resting blinking rate. Does that perhaps provide an approach to some mathematical treatment of my intuitive model and perhaps even a way to develop some sort of empirical testing?
It always helped me to understand this concept by not thinking of space and time as separate but as linked as Einstein did by describing it as spacetime. So if they are connected then changing the speed you are traveling through one should always change the speed you are traveling through the other. Gravity and acceleration are just a means to change the speed you are traveling through spacetime.
I love that you ask yourself the same "natural" questions i ask myself as the video progresses and you answer them one by one.
The speed of light isn't a constant; it's more likely that it's the amount of time it takes for a given area of space to process all the things that need to happen. A black hole isn't an infinite dense point in space, it's a powerful energy conversion machine. With more matter/energy you have slower time, which is effectively the frame rate of the universe.
The reason light can't escape it isn't due to gravity, it's due to the way energy currents function in space. These energy currents hold the galaxy together, but if there is more energy than can be converted and sent into the galaxy, you'll get a pulsar, which is the method it uses to dump energy. These would be equal to the auroras on the planets.
Hope this helps!
edit: Aging slower is just a matter of each frame taking longer to process. Going fast means more processing per frame. It's a lot simpler than this mathematical model being described.
Space lag ... I like it.
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.
Brilliant is exactly the right word to describe you. That explanation was so clear and to the point. Please keep making videos like these they are marvelous.
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.
My village in Uganda is poor. We enjoy your videos. Thank you.
This is one of the best I have heard when it comes to explaining these complex concepts
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
This is by far the video of the millennium to me.. for someone who studied physics during non youtube times..👍
Pls continue to make these videos .....dont stop.
First thing that's wrong with that scene in interstellar, is that the planet is within that light ring around the black hole. The gravity is so great that it traps the light into a "ring". That LIGHT RING around the black hole is going to lie well within the Roche limit. Planets can't exist there, because the immense gravitational forces would rip them apart.
WRT the person at the center of the spaceship, the person at the far end isn't moving and remains at rest (assuming both are standing). If their relative velocity is the same but their time flows differently due to varying acceleration and increased gravity, it would be strange. The person at the center would see the one at the far end waving their hand in slow motion... your explanation just made another of reason of time dilation more clear to me!
@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 ).
I discovered this channel and oh my i am just binge watching every video. Your explanation are brilliant. Better then veritasiums explanation. Keep going 🏆
This playlist was way beyond excellent, thanks. I’ll have to watch it again so the concepts become easier, then I’ll explain it to others
We need more videos like this and less mindless nonsense on this platform. Good on you sir.
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😊.....
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.
OK. @5:11, it talked about the ground accelerated to meet the apple & not the apple falling down.
So, the next time when you are accused of landing a devastating punch on someone face, you can defend your act by claiming you did not punch someone face mightily. It was the other person's face accelerating at a stupefied rate toward your fist.
That is your scientific get out of jail explanation.
This is a good explanation but i already had a decent understanding that time is dilated by gravity due to proximity 😂😂
However, this was extremely handy. Being able to explain a concept is a tough task. Thanks for taking the effort to make Einstein's explanation simple enough to understand easily
I hate ads in the middle of videos, but I get that it lets you have a source of income without having the ad interruptions all throughout the video. I do have to say that transition into the ad was pure comedy though. Made me giggle pretty strongly.
Hi, and what about moving faster? If we have strong gravity/acceleration time ticks slower. But if you move fast without any acceleration you won't feel and gravity/force but you still should age slower than someone who is not. What's the difference?
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?? 😂
Sir, you just blew my mind. Thank you for this
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
Ok. Here's the problem though: How can black holes come into existence, given the time dilation around them?
Let's first examine an object falling into the black hole. As the object gets closer, time slows down for it AS PERCEIVED FROM AN OUTSIDE OBSERVER. That means, for the observer, the object's fall towards the black hole gets slower and slower. From the perspective of someone inside the falling object, and looking back out, time in the rest of the universe speeds up more and more: So decades pass in mere minutes.
Ok, now: As I understand it, by the time the object reaches the event horizon, its clock slows to zero (or the outside clocks speed up to infinity).
What that must mean though for an outside observer is that the object comes to a virtual standstill before it can ever reach the event horizon.
From the perspective of the object, on the other hand, they see the complete history of the universe pass on the outside (even if the universe was eternal) BEFORE they enter the event horizon.
So: That means that for the outside observer (for example someone on earth) NOTHING can EVER fall into the black hole completely (during our lifetime, the lifetime of the earth, or even the lifetime of the universe). Instead, all objects approaching the black hole, appear frozen in time and space at some distance from the event horizon.
--If this is not so, it would be great if someone could point out where my logic fails me here.
Ok, now let's take this further and look at how the black hole comes into existence in the first place:
A massive star is collapsing on itself and the matter at its center is getting more and more dense, as the gravity it “produces” gets stronger and stronger. But that means that time at the center of the collapsing star starts to slow down more and more, which means that-again for the outside observer-this collapse itself should appear to happen more and more slowly.
As the star gets closer and closer to becoming a black hole and forming an event horizon, this time dilation, again, should become so extreme that it slows time down to almost-and eventually exactly-zero, before that matter can ever become dense enough to form a black hole. Again, not from the perspective of the collapsing star itself, but from the perspective of the entire universe surrounding it.
But that means, that it is not possible for a black hole to actually finish its process of formation during the lifetime of the Universe.
I am not confused here: I know that from the perspective of the collapsing star there is no problem: It simply keeps collapsing, and may even do so faster and faster-but just like for the object falling into the black hole, from the perspective of the collapsing star, the time in universe around it goes faster and faster and the star would “see” the entire eternal history of the universe pass, by the time it becomes an actual black hole. Again, from the outside perspective, the collapse of the star should slow down more and more, so much so, that it will appear frozen, before it ever becomes a black hole.
So: how can black holes ever form within the lifetime of the universe? They could still exist, but they would have had to have been there from the very beginning. They could not have formed at any point thereafter. where am I missing something?
One point I am not 100% certain of is, if the event horizon actually represents the point where time slows to zero-since it is the point where light cannot escape, it seems to me that it is the point where time would also slow to zero, but even if it is not, there would still have to be such a point somewhere deep in the black hole, where the boundary of the singularity exists-so I am not convinced that this even makes a difference.
I know, chances that you will actually read this comment are minuscule at this point, but a video on explaining why black holes can form in a region of space where clocks move at zero speed compared to the outside universe, would be really awesome!
Cheers! Love your explanations!
This one gets me the speed of light is constant for all observers... time dilation means seconds pass differently so light has to slow down in gravitational field in order to match time dilation so that speed remains the same. And vice versa.
But then in the same breath you cannot say it slows down because it moves same distance per second although the second has taken longer