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Question, since gravity is determined by the mass of an object, and since e=mc^2 can be arranged to form m=e/c^2, does this imply that an object will have a greater gravitational force and hence will warp spacetime around the object to a greater extent, the greater velocity it has (due to the fact greater velocity implies a greater kinetic energy)? Or am I thinking about it wrong
Everyone, if you liked this video, you can help more people find it in their RU-vid searches by clicking the Like button and writing a comment. I will be posting more new physics videos soon, so please subscribe if you want to get notifications when they are ready. Links to some of the videos I have already made are available at the end of the video above. Thanks.
Hello Eugene - thanks for this great video, I watch it all over from time to time, it is so fascinating. The only special thing is the background music being to loud over the nice lady's voice, especially when I try to concentrate... Thank you again for the nice video, really admirable!
Hey, the proper time is always the short one. The longer time (time dilatation) is the one that the "Earth" guys observes. Both TIMES are correct. Just like a car moves away from you, it gets smaller and smaller, but the car is always the same :) Hope it helps...
Hi, as a retired science teacher, I can say that this video is outstanding. It has made the understanding of General Relative easier to get one's head around the concept. Very well done. Nicholas Marino FL.
In the last part, doesn't sarah's clock run faster irrespective of whether adam accelerates or not. I have seen several videos where it says acceleration has nothing to do with it.
Dominic, the videos which say that acceleration has nothing to do with it are only dealing with Special Relativity. I am discussing it from the point of view of General Relativity, which is the more complete theory. I go into the details of this specific issue in my video on the Twin Paradox at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-bjHLboK2M1g.html
@@EugeneKhutoryansky well I have a question. Why do we think that light's speed is same for all observers. Suppose that I am moving at light's speed now, so I will notice that light has stopped moving. So according to me light's speed is 0 but for other observers on Earth it will be still c. Where am I wrong?
It's actually good to see someone who actually knows what he's talking about doing such an elegant animation. Its been 6 years since I first saw this video. Back then I didn't understand anything. Now, with a physics degree I can appreciate it much better. Seen some of your videos. Please continue.
Eugene Khutoryansky is humanity's hero! so much time and effort (not to mention sheer brilliance) into making these concepts accessible to the general public!
Alper Angın : Here’s my answer to Abdurrehman farooq : Maybe it could be clearer with another extra step: the mirror could be on another spaceship running parallel to Adam’s one.
I remember watching this video as a kid and falling in love with the beauty of physics and the background music, it gave me the inspiration to learn the piano and perfect it. Thank you for that.
How can time slow down inside a moving vehicle to rectify the otherwise inevitable - apparently - problem of 'light travelling faster than light speed which is, as a principal of physics, CONSTANT, if this would cause any light that started to travel inside the vehicle just before the vehicle moved to slow down and 'travel slower than the speed of light' which is, also, according to Maxwell's principal, 'impossible'? Plus, if light reflecting off OUTER surfaces of a moving vehicle would affect the light as a tennis ball 'slowly' hitting a speeding train would be affected in terms of its speed increasing on reflection without, that is, the slowing down of time OUTSIDE the moving train, then either time does not slow down outside a moving vehicle and Maxwell's principal is violated or time slows down OUTSIDE a moving vehicle - as well as inside - and Einstein's theory of 'relative time' is wrong?
@@foroyalty I don't understand Maxwell equation but I too have doubt in theory of relativity. Can you please explain me Maxwell equation simply. I am not good at math.
is it sad tho? its your interpretation of sad. but why do you interpretate these tones as sad? as far as we know there is actually no logic behind it. high slow tones indicate sadness? what in evolution has caused that if thats the case? i wonder.
@@hsaccount_ it's not "high slow tones". Anytime you try to associate an emotion with a rule in art you will find a counterexample. That's the beauty of art, we know if something is beautiful, sad, happy, dark, but we don't know why :)
@@JuankQuinteroMejia From his mind's point of view, the video goes at the speed of light and it's clock moves faster, but from the video's point of view, the video stands still but it's Jim's mind that gets accelerated by a gravitational force.
Wow this is an excellent video. I go to school every day hoping my teacher's would teach me something like this but instead they bore me with the very basics of a plant for e.g label all the parts of a plant. I wish science in schools would be taken more seriously.
Lol there's no practical application for this unless you go into physics, and to actually understand this you'd probably need a few years of fundamental knowledge in physics, stop whining about school. (and maybe take physics instead of biology)
Jayo Caine have a look at Labibs education playlist on my channel, I have made a few videos regarding various aspects of science and then you may understand why I like physics...O and please go easy on me considering I am only eight years old. Thanx.
this is truly one of the best video on all yt. i regularly come back to rewatch it, again and again, there is something that fascinates me but i can't exactly point out what it is.
Tesla on relativity: “The theory, wraps all these errors & fallacies and clothes then in magnificent mathematical garb which fascinates, dazzles and makes people BLIND to the underlying errors. The theory is like a beggar clothed in purple WHOM IGNORANT PEOPLE take for a king. It’s exponents are very brilliant men, but they are meta-physicists rather than SCIENTISTS. ***NOT A SINGLE ONE OF THE RELATIVITY PROPOSITIONS HAS BEEN PROVED***”
Exactly ten years ago (I was 15 years old), I discovered this video. Before that, I am already interested in sciences and mathematics. After watching the video, I was mind blown and having existential crisis for a few days. From that moment, I started to read a lot of physics book and math book to be able to understand general relativity. I understood special relativity mathematically during my college majored in physics. For general relativity, it took me until now, my math is still not enough to understand it. I am currently a research student doing master degree in quantum dynamical semigroup. Without your video, it is hard to imagine to be able to get to where I am now.
Thanks. I am glad that my video made such a positive impact. By the way, in case you haven't already seen it, I have a video discussing the mathematics of General Relativity (Einstein's Field Equations) at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-UfThVvBWZxM.html
Hey. so If I travel at near light speed and time slows from hours to seconds for me ... does my biological body follows the time?. We can't survive without food and water. travelling for an hour at near lightspeed is equal to months on earth. how can my body survive?
I'm pretty sure time will be taken out of Space time. Gravity is just a physical effect on clocks and atoms making us think time has been changed, but it hasn't, as clocks are not the definition of time. Time marches on at a steady rate irrespective of the existence of clocks.
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Can I upload it , by editing it in Hindi version. I am ready to share half revenue from all these videos. Because people wants to understand it in Hindi. Really if you agree. Email - kanaujiyavimleshkumar@gmail.com
@@vimleshkumarkanaujiya No, you can not upload copies of my videos. Subtitles are available on my channel in Hindi and in many other languages. To see the subtitles, click on the gear symbol under the video, then click on "subtitles." Then select the language (You may need to scroll up and down to see all the languages available).
I don't know if Einstein can taught a 12 year old boy 'What is my theory of relativity'.But you did this . Great job..👌👌👌👌👍👍👍👍.I have never seen a educational video which can teach us this simple.
you're right in my opinion. But i also like Leonard Susskind, Stanford University professor explaining the math: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-toGH5BdgRZ4.html
I love it how you connect your explanations with your atmospheric animations and the calming music. This way those topics regain the beauty that they deserve.
After 4 videos I finally understand it and it explains a lot about space. This video was by far the best as it did not just repeat Einstein's theory but actually explained it in a new modern way
This was the video that got me started on my path to become a theoretical physicist. This video legitimately changed my life! But I have to say Eugene, you’ve improved tremendously on these since you made this. Ever think of remaking this video to remove some of the more whimsical bits or correct sections like the relativistic mass section?
@@seralelix There is nothing "wrong" with the relativistic mass section, but there are many people who think that the concept of relativistic mass should never be used. I discuss this in detail in my video at ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-AU_O9yrgwhk.html
A really simple, concise explanation of Relativity. I especially enjoyed the fact that you pointed out that because gravity is the curvature of space/time it is not actually a force. Gravity does not pull on objects. It is the curvature of space/time that makes objects traveling in a straight line in curved space/time appear to be pulled towards each other. I get so frustrated when I see very famous and popular scientific educators neglect to mention this. Instead they mention the curvature of space/time and then continue to describe gravity as a pull. I realize that it is an attempt to make the concept of gravity easier to understand but, in my opinion it is a disservice to true scientific education. I think even most layman can grasp the reality when presented properly as you have.
I see the dent and all, but one still assumes objects to travel "downhill" which is due to the preconcieved notion of gravity being a "pull" in the first place??
xXsakkelaoXx An understandable misconception as, given what we observe, your explanation makes perfect sense. In reality gravity would actually be more of a push that we receive from space/time itself. I don't know if you have ever seen one of those big funnels that you drop coins into and watch the spiral down into the centre? The coin rolls around the inside of the funnel because it actually wants to go in a straight line. However the "push" of the funnel makes it orbit instead. In this case a decaying orbit, but if you could get that coin rolling really fast it could acheive a stable orbit the around the centre.
James Toupin Gravity is a very mysterious thing, especially when you think of it along side space/time - here is an interesting thought, if an astronaut were to leave the gravitational curvature of the earth --- and he placed an object next to his mass that was say 1000 times smaller, or 10,000 times smaller, would that object then orbit him? If the answer is no because the mass is not great enough to "Dent" the fabric of space, Then you have to wonder if it is "Layered" and how big is each layer? The reason for me saying that is because when I think about it, if it was a consistent fabric then why should the sun be big enough to bend it? If the sun is, then surly an entire galaxy mass should be enough to cause a rather big dent which would nullify the effects of the inner dents? Also curiously if the answer was no, and you then accelerated the poor spaceman inside the galaxy along with his ball we will call "Wilson" haha to near the speed of light his mass would become big enough that the ball would orbit? and also if his mass accelerated to such lengths that it becomes near infinite if you had enough power that is... Then surly the denting of that infinite mass would throw off a few orbits of say, the complete solar system? The more deep you think about the subject, the more questions there are, personally I have always accepted the standard theory of gravity and thinking about it leads to endless questions, poor albert.
I understand the concept, but the question is why would it orbit so slowly? When the earth orbits the sun quicker for example? The obvious answer is Mass - Yet the sun is much smaller compared to the galaxy than earth to the sun, and in ratio the grain of salt compared to the man, so if you picture the indentation the galaxy must make, should that not make for example the centre of the galaxy's gravity a lot more dense and nullify anything holding orbit? the same as the earth nullifies our ability to have a grain of salt orbiting us on earth?
I discovet yout channel yesterday, and running through all the video ! Brillant job! Very educative and visualized ! Keep going it’s fabulous! A french guy
+AWarmCoffee yes dude i saw that movie over 4 time's probably, but cant understand the basic concept, after this presentation i watched another time, and i clearly understood ..
I was like "oh I dont know what the theory of relativity is, Even though I have heard of it many times, I want to know what it is" Holy moly this is heavy stuff! Now I realized why Einstein is a known physicist and not me
Such charismatic music and setting. It would have been a beautiful nostalgia for me had I watched it as a kid. The music is so fitting as it feels as mysterious as the nature of spacetime, or the nature of universe and perception in general. ❤
Interesting. Very complex, and to think a man thought of this, and disproved what everyone in that time thought of space it's self. this puts a good visual in my head of his theory, thanks for the video.
Over the last year I have become a physics junky. Your videos were some of my 1st inspirations. Thank you for all your hard work! I can't wait for the next one.
+Jonathan Jacobi I'm really gratefull for the explanation! Very interesting ! However i wished more than a few time during the video there was a stop button allowing me to stop the music and keep the commentary.
Музыка вместе с информацией создают ощущение, в каком удивительном мире мы живём! Music and information in this video makes me feel what's the astonishing world we live!
An electron gets pulled up for speeding. The officer says "I clocked you at 186,000 miles per second". The electron says "Bloody hell, now I'm lost..."
I very much appreciate Eugene for such brilliant content on a topic that so hard to express. And for those of u who are still learning 2D, 3D and Vector Mathematics, just try to parallel transport a vector on the surface of a cylinder and a cone. U will the magic which Einstein fomulated in very complex Mathematics.
I think it's the first (or one of the firsts) videos who teached me about basics of relativity, which is a kind of must-know knowledge for me now. I think it was few years ago. Now I had to go back cause I actually started to feel like the more I think about, the less I know.
yes. gravitaion is nothing but a curvature in time space. imagine 4 people holding a bed sheet tightly that it is completely straight. now put 4 cricket balls at all the 4 ends. the balls will not move because the bedsheet is completey straight. but if you put a football in the middle of the bedsheet. the weight of football will create a curvature and all the cricket balls (the smallers particles) will be attracted to it. this force is what we called gravitaional force. the bigger the object the bigger the mass the bigger the curvature and more the gravity. hope you understand now ☺
So let's say we invent a spaceship that can move at the speed of light, that means we can travel from one end to the other end of the universe in one human lifetime or just a few seconds of it while on the earth it seems as we traveled for 93+ billion years right? how do we know the universe is 13.8 billion years old if time is relative? I must have made a mistake here.. right?
No time would have passed if you traveled at the speed of light, at least no time from an observers perspective. Theory indicates time should still pass on the ship, but if time slowed down Infinitely for an observer it is subir for debate as to whether you would experience the time.
Nat King Coules yah u r right the universe is 13.8 billion years old according to our perspective but it might be 10000 times older or just 1 hour old according to different perspectives
I watched this video even before my high school and had loved it then. Even now when I'm in university it feels equally intresting and awesome, and this video reminds me of those days. I never thought that a RU-vid video could carry so much of nostalgia 😃
So I have a question, if any one can answer it or point me in the right direction that would be great. In this video when they're talking about some one returning from a high speed journey across the universe and only aging a fraction of what everyone on earth would age. They mention that the person in the space ship, on the way home, would see time on earth passing very quickly because they're traveling at it so quickly. Wouldn't the people on earth also see the space ship's time running very fast because they're seeing the same thing in terms of relativity. And if that's the case then the aging between the people on earth and the person in the spaceship would be equal. Here's how I'm looking at it. In terms of relativity, the people on earth and the person in the space ship are seeing the same thing throughout the entire journey. When the space ship is traveling away from earth, the person in the spaceship is seeing the earth travel away from him just like the people on earth are seeing the space ship travel away from them. On the way back the person in the space ship is seeing earth travel towards them just like the people on earth are seeing the spaceship travel towards them. So wouldn't the aging differences all cancel out?
Honestly this is a great question, because on the surface it does appear that you would be correct. However I have a feeling that our assumptions are probably wrong...we just need someone to explain why we are.
Blake Mcdonald Each person see's the other person's clock as going slower only so long as no one is accelerating. From Adam's point of view, when he tries to turn around, he will think that there is a gravitational force balancing out the force from his rockets, causing him to remain still. From his point of view, this gravitational field will cause Sarah's clock to run faster than his. This is why Sarah and Adam will agree that Sarah is older when he returns.
Eugene Khutoryansky I've had the same question as Blake regarding the canceling out issue since, from each of the two perspectives, the other is aging faster. Your explanation doesn't solve this problem for me. You say that it is because Adam is accelerating to turn around that causes Sarah to permanently age more than Adam. But if everything is relative depending on the viewpoint, couldn't we just as easily say that it is actually Sarah (and the earth) that are accelerating to "turn around" to go back towards Adam (rather than the other way around)? So looking at it from that viewpoint, wouldn't Adam age more than Sarah?
frogsforall What is different in the two cases is that for Adam to believe that he is standing still during the moment he fires his rockets, he needs to believe that there is an external gravitational field during this moment. On the other hand, Sarah does not need to believe that there was ever any external gravitational field, and from her perspective this extra gravitational field never existed. From Sarah’s point of view, she is older when Adam returns because time on his ship slowed down while he was moving fast. From Adam’s point of view, Sarah is older when he returns because there the extra gravitational force caused clocks on Earth to move faster than clocks on his ship. Sarah will not say the same thing about Adam, because from her point of view this extra gravitational field never existed.
Gravitational field or not, unless there is a third point of perspective, in terms of relativity Adam and Sarah are seeing the exact same thing. Noting is standing still in the universe. As Adam fires his rockets, who's to say he isn't just standing still and the earth is moving towards him. For example, if you were swimming against the current in a river and something floating with the current was coming towards you. Without a third point of perspective its impossible to tell who's moving and who's standing still. If thats the case, Adam and Sarah would see the exact same thing. First something traveling away from them, then something traveling towards them. And all aging differences would cancel out. I know you're trying to explain this to us but I still can't see why one would age faster then the other.
I was directed here by a commenter on a video about Azumanga Daioh (Pico the Spicy Wardlord), as the narrator for this video is the english voice actress for Osaka from said series. In the series, it is loosely implied that Osaka sets out to become a teacher after high school, so it's really cool to see the VA teaching now!
If Black holes can cause infinite curvature then 1) How is the universe flat? 2) How can gravitons(if they exist) themselves escape from it? 3) curvature is caused by mass. So infinite curvature = infinite mass. A star dies and forms a black hole then where did all this extra mass come from??! Sorry if any questions are dumb.
Rohith Srivathsav 1) A flat Universe means a Universe in which euclidian geometry is obeyed. A triange in our Universe will have its angles add up to 180 degrees. Compare this to a triangle formed on a sphere's surface: the angles will add up to more than 180 degrees. 2) I don't know. Personally I assume that gravitons don't even exist, but I don't really know the matter so well that I could give an educated opinion on the matter. I think that if gravity isn't a force, but a curvature in space-time, then there is no need for a particle to carry information of a non-existent force. 3) Curvature is indeed caused by mass, but you don't need infinite mass to create infinite curvature. A black hole doesn't have infinite mass, it has infinite density. All of the mass of a black hole is located in a single point in space. Since a point has zero dimensions, a finite amount of mass exists in infinitely small volume. Eugene Khutoryansky Please correct me on this, if I'm wrong on something. Could I also ask you a question on this? It came to my mind that density is defined as mass divided by volume. Since a black hole has zero volume, is there even such thing as "density", or is it undefined? Or is the density infinite, since the limit of mass/volume approaches infinity, as volume -> 0?
***** Ohk thanks...i figured out the 3rd one myself..i was wrong. Mahn this subject is so confusing..the more videos i watch the more doubts i get and my head goes boom xD no idea when will i fully understand this stuff :/
Rohith Srivathsav 1 universe is not flat.space time is flat .universe is flat in our perispective .it is like looking at a sheet of steel from above without looking at its other dimensions. 2 gravitons are elementary particles of nature having a mass of 0.and anything having mass of zero is not an object.rather it is like a wave until measured.for more info read brief history of time book chapter elementary paricles. 3 to be specific the curvature of a blackhole does end somewhere but at the other side of space time.its like making two dots on paper and then folding it to connect them.
Speed of light is constant, everyone teaches bcoz it is a number, 3,00,000km per sec. So long it took to understand the real principle i.e., speed of light watching from different observer is same i.e., same light both observer are seeing as reality. So light is light no more constant number. Thanks🙏🙏🙏
I repeatedly watch this video, may be in autumn more than in other seasons. It takes me faraway to the remote future of mankind, thousands or even millions of years, when concepts like space travel, travelling near the spead of light, and difference in time flow, will be more familiar, and when human will have evolved further.
This is one of the best video to explain theory of relativity. I tried many sources to understand but this was the source which made me most nearest to understand Completely
