Special Relativity
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- Опубликовано: 19 июн 2024
- How can we describe the speed of light? Are time and space absolute? How do cosmic muons manage to reach the ground? All these answers in 13 minutes!
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Alessandro Roussel,
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"With great speed comes great time dilation"
-Albert Einstein
He didn't say that too..
@@shaktikashyap0601 How do you know?
Also, the *Length Contraction*
he's skinny and his clock runs a little slow, but gd can he move
Ya
This video is so highly underrated I can't believe this.
Agree 100%
I rate it highly!
But its a newer channel.
Very true💯
Time is time. Gtfo! #brainexplodes
Well, its relatively underrated
Thank you. Best explanation of SR I've ever seen.
🙏
Yeah, these videos better help me understand the concept than any others of their kind. The visuals do a great job especially.
@@ScienceClicEN I think you were mistaken at the very end.
Special relativity is well capable of describing any kind of motion with the help of calculus. General relativity is only needed when talking about gravity
@@ScienceClicEN 🙏
@@ScienceClicEN I don't know.. dialect is giving him a run for his money now.
Fortunately for me, I had watched "We all move at the speed of light" (Nov 8 2018) and "A new way to visualize General Relativity (which is brilliant, BTW!) before this, which helped understand this. These videos are fantastic!
Why would the rear be in the future and the front in the past?
@@thememaster7 Rear would be in the future only through the perspective of the observer who is observing the spaceship and is not actually on it.
It would be in future because the light from the rear end of the ship is reaching the observer at a faster speed and for him the events occuring on it pass quickly e.g the age of the person in the rear of the spaceship,time.
For people on the spaceship everything's happening at a normal rate.
It is not a common phenomenon it would only occur if the spaceship is traveling at the speed of the light which is impossible.
@@asadullahmaan3482 It wasn't because the light from the rear end of the ship is reaching the observer at a faster speed, remember that the light speed is an invariant.
How is it possible for this kind of channel to be so underrated. Amazing explanations, great graphics, beautiful content....
This is by far the best explanation I've seen after getting confused by watching 15+ videos about relativity. Thx bro :)
Why is the rear of the ship is in the future? u can't say. Therefore I don't think it's a very good explanation
@@alwaysdisputin9930 I think it's a bunch of nonsense.
the idea that time itself is different on the front and the back of the spaceship to an external observer gave me a whole new perspective and intuition about the theory. I've never seen such an explanation. Thanks so much :)
In gravity between head and fits time is different. Your legs are in the future
@@tomekstanekno your legs are in the past because time slows down near more gravity (earth) & time pass faster as we move away from earth (so our heads are on the future)
..... Head older than legs.....
The description of length contraction being due to seeing the front, middle and end of the ship at different times is very important. Imagine of the ship was changing color very quickly in the ships reference frame. The observer on earth would see the contracted ship as rainbow colored.
I don't get it. Why would the back of the ship be in the future and the front be in the past from the observer on Earth?
Shouldn't it be the other way around?
@@thememaster7 "Rear would be in the future only through the perspective of the observer who is observing the spaceship and is not actually on it.
It would be in future because the light from the rear end of the ship is reaching the observer at a faster speed and for him the events occuring on it pass quickly e.g the age of the person in the rear of the spaceship,time.
For people on the spaceship everything's happening at a normal rate.
It is not a common phenomenon it would only occur if the spaceship is traveling at the speed of the light which is impossible." > i had the same question, but someone else answered above :) and i got it ahah
@@marialuispinto8779 Doesn't that mean the rear light reaches the observer sooner? Later is future.
@@marialuispinto8779 I get it now. Thanks
Stumbled upon this channel and I think it has the best explanation on the entire internet
Is it fair to say that length dilation is a physical manifestation of an object bending into the time dimension?
Yes ! The object gets "inclined" in spacetime, and that changes its apparent length in space
The object itself does not bend in the usual sense. If it is brittle, it would not break solely due to traveling fast (it might break due to other effects involving how it is accelerated).
@@david203 Yes thank you. Maybe I should have described in as a rotation into the time dimension instead.
@@elindauer This idea of "rotation into the time dimension" is, as far as I can tell, not part of standard physics. I did find an interesting proposal at www.physicsforums.com/threads/theory-underlying-sr-the-time-dimension-is-moving-relative-to-the-spatial-dimension.80559/, but since this has as yet to be accepted, it must be considered speculation. I'm not educated enough in physics to judge this theory.
@@david203 I took my master's in physics and in my experience, it seems pretty standard. There is one qualification though: the "distance" between two points in 4D spacetime is defined slightly differently than the distance between two points in a 4D space. This difference affects other geometric concepts such as rotation, angle etc. Consequently, a rotation into the time dimension behaves slightly differently than an ordinary rotation. In practises this means the trigonometric functions sin(x), cos(x) and tan(x) should be replaced with sinh(x), cosh(x) and tanh(x), but otherwise the equations look pretty much the same.
Everyone always makes it complicated. They speak of the speed of light as being an invariant, and then proceed to relate everything to that one invariant alone. Well it is a heck of a lot easier to understand special relativity(SR) if you take into account the second invariant. Everything that exists within the 4D environment known as space-time, is in motion exactly as much as is light in motion across space. The only difference is that for mass particles, a percentage of that motion, is across the dimension of time. So the point is, since you are constantly on the move within space-time, all you can do is change your direction of travel. Now if you create a very simple geometric representation of that ongoing motion within space-time, you can use it to derive the SR mathematical equations, and complete this task in mere minutes. This task includes deriving the Lorentz transformation equations as well.
I'd argue that’s definitely not "easier way to understand SR". Because if you're explaining SR to someone, they probably don't have any idea what you're talking (including 4D space-time and every object's motion being a component of c). They are probably expecting you to explain what’s wrong with Galelian Transformation? Why do we need Lorentz Transformation at all? That’s why it's necessary to mention, we see light speed being constant which breaks Galelian Transformation. That’s why you need a new type of transformation that gives us a finite constant speed for light.
@@shawon265 I understand what you mean. I did not have the opportunity to acquire any physics education, so in my case I had nothing to compare to, to relate to, or to correct. In turn, I had nothing to hold me back, nor throw me off track. I simply analyzed "Motion" to determine what it is, and what it is that is required to make motion possible.
Just watch the video „we all move at the speed of light“ on this channel!
The point about deriving the Lorentz function (more precisely, the reciprocal) from the constant spacetime speed is a very good one. Before I figured it out, the Lorentz function was just a some numbers and a variable, but afterwards it was just as abvious as why a cubes volume is a^3.
Here's how to do it. Construct a 2-dimensional spacetime graph with 1 D of speed through time, v_t, and 1 D of the magnitude of the speed through space, v_s. Because v_t + v_s = c, the graph is part of a circle, which is the same as the graph for the reciprocal Lorentz function, γ = sqrt(1+(v_s)^2); you will see why soon. The circle in the spacetime graph can be described by c^2 = (v_t)^2 + (v_s)^2. C is the constant speed through spacetime and is the only objective speed, so we can set c = 1, and therefore: 1 = (v_t)^2 + (v_s)^2. Because the of way the reciprocal Lorentz function is defined, it describes the same thing as v_t: the speed through time. For example when γ = 0.5, your time elapses 0.5 as fast the person observing you; therefore: 1 = γ^2 + (v_s)^2 --> 1 - (v_s)^2 = γ^2 --> γ = sqrt(1-(v_s)^2). There is the lorentz factor!
The easiest way to understand special relativity is that it’s BS. A magic trick comprised of assumptions and disregard for the physics of light, producing a ridiculous conclusion.
I'm 15 years old..and I understood this video fully..
what a great explanation!
I’m 14 and I did too
If you can explain a concept to a 15 year old in a simplified manner only then you have u understood it yourself
I've been traveling at greater than light speed and thus, I haven't been born yet.
Why is the rear of the ship is in the future? u can't say. Therefore I don't think this video did give a "great explanation"
@@alwaysdisputin9930 it is in the future because of how light moves in the spaceship the light was slower on the front than the back therefore there are different time dilation in the ship. Because c=const it has to mean that from an outside standpoint time goes faster for the back so it will be constant and time moves slower in the front so c will still be c
This is literally the type of video I want to visualise special relativity
Really well done. I am re-reading brian Greene's book the "elegant Universe" and I am retired from being a chef. So these videos are a huge help.
The only way to progress in our quest to understand the universe and the life is to watch this kind of videos and renounce to our old common understandings. These videos are a real step toward that goal! Thanks!
Great as usual. One thing I would state differently and place it in the beginning. I never hear anyone making it this simple.
“If you hold speed constant at all times no matter what the circumstance, something else has to give”.
Given light’s velocity is based on distance (length and time), then if you hold light velocity constant in all observers views such that light stays constant in their reference frames and, also, if they look at some one else’s reference frame moving or not, then those who use light to observe find that something has to give. That would be length and time.
Not sure if a similar construct could be applied to an observer using another method such as sound speed. If you hold the speed sound constant in all mediums, then the materials would require to offer the same impedance to sound. For example, air and water. Not so much.
Light in vacuum travels with the impedance space time (ST) offers to propagation of electric and magnetic fields but as far as we know, ST does not vary in impedance or vary as a medium to affect c even when curved.
Very well explained. You took a difficult concept, and made it easy for people to understand.
Thank you !! By the way i'm a theoretical n mathematical physicist, can u give me the right to translate and dubbing your videos into Arabic language, there are a lot of people who need to feed their brains, please ❤
You can contribute to the subtitles on the French channel. Also I am planning to translate the videos to arabic, I have already done some voice tests ;)
@@ScienceClicEN you can speak Arabic too??, watching a scientific video with subtitle is not effective as watching a dubbed one. Thank you again!
The french channel has more vids.
Most channels allow community sub titles. Just work your subs.
Maybe you could also copy your subs from the French channel to the English one. Visual content is.identical.
@@Benoit-Pierre not anymore that sucks :(
You Sir, are a LEGEND!!!
understanding complex subjects of physics is necessary and not easy. Your videos are very clear and simple! Your efforts to prepare your videos are very much deserving of gratitude and recognition !! Thanks a lot. I subscribe, like and share. Good luck.
One of the best visual demonstrations of Special Relativity out there, made me subscribe. Gonna start the GR series
very impressive! Glad that I've found you
Thank you !
Very intuitive. All videos are amazing. Well done.
The most simple explanation of the most complex concepts of time dilation & length contraction. Bravo!
Why is the rear of the ship is in the future? u can't say. Therefore I think this explanation is too simple i.e. it has been dumbed down
As I continue to watch this, it is seriously blowing my mind with "...in the past" with light ray ...in the future" light ray portion. I really never understood until I this video, it was explained so well! Thanks to my nephew for this link 👍👍
I love everything about your videos.
Btw, your background music is perfect for contemplation
Keep up the good work!
I thought the same thing about the music. I wish I knew the soundtrack of it.
This channel is gold!
Your Way Of Teaching Is Extraordinary....
Everything You Tell Is Understandable❤️
I can't stop coming back to these eye opening videos. They allow you to actually understand these concepts at a deeper level
Why is the rear of the ship is in the future? u can't say. Therefore I don't think this video allows you to "actually understand these concepts at a deeper level"
Definition of Relativity: 0:11
Ball throw example into speed of light: 1:02
Two events occur differently depending on observer: 2:33
Previous scenario with time: 4:20
Length contraction: 5:38
Time dilation: 7:12
Summary example using muons(?): 9:03
Conclusion: 11:03
This video is non sense and completely wrong. Explain how a person traveling the speed of light can shine a flashlight forward and see it hit a wall in front of them. You can’t! It would be a flat circle of light stretching horizontally across from the light then illuminating behind you. The light can not break the speed of light with an initial inertia like a baseball being tossed on a bus. You would be molecular frozen like at absolute zero temperature and couldn’t even put your hand in front of your face because your hand would then be moving faster than the speed of light to an outside observer.
@@farbeyondbeautifuldesign9804 Because the spaceship has mass that prevents it from travelling at the speed of light, so it can never be the speed of light. At that speed, time dilation causes the speed of light forward to appear to happen at the speed of light, while the universe speeds up around you.
This is sooo underrated😥 The best explanation ive ever heard
Why is the rear of the ship is in the future? u can't say. Therefore I don't think it's a very good explanation
DUDE THIS IS SO MUCH EASIER TO UNDERSTAND THAN ANY OTHER VIDEOS! HOW COME THIS IS UNDERRATED?!
A superb explanation of special relativity. Love the spooky sci-fi instrumental music in the background too!
This helped me to clarify some ideas :D
This channel is highly underrated.
Glad to find this channel buddy! Your content is simply too good.
Best science channel on youtube.
If taking the younger/older example into account: what would happen if we collapse these realities in one place? If we land the ship on Earth, the people there would have to see one older and one younger, but the people inside the ship would have to see both at the same age (it's the same things for the clocks. would they be synched or not? it's the same example, afterall)
To land a ship on Earth you have to deccelerate it, and acceleration changing perspective. If they are in sync on the ship, they'll be in sinc on Earth, because they experienced the same acceleration
OMG I HAVE BEEN TRYING TO UNDERSTAND THIS FROM SOO LONG!!! THANK YOU THIS IS THE BESTEST VIDEO
Try to improve your Grammar too ,btw which place from India are u,
@@augijyotbali2131 can you please point out my mistake cause I don't see any
@@parminderkaur4438 you had written form and bestest aint a word "best" is the superlative of "good"
@@augijyotbali2131 OMG update ur vocab u don't know this also bestest is a word (though informal) go search it on Google AND form was written by mistake I meant from
@@parminderkaur4438 whatever first know that grammar doesn't include ",slangs"
6:57 This animation made me realize that length contraction is analogous to rotation in 4D spacetime. Holy shit.
Wow
Great animations and content. the only channel in which General relativity and space time fabric made sense.
An absolute masterpiece.
Thanks, uploader!
Does that mean that from photon's point of view, it travels from one point to another instantaneously? And, does it "see" the world around it as a flat projection in the direction of its movement?
Exactly yes!
I dont think terms like "photon's point of view" or what "a photon sees" have any sensible meaning, unlike say a muon's point of view etc.
SR is really Hard.
Wow. Fantastic explanation. Love your videos!
This video was awesome. Shared it with my mom and dad who aren't well-versed in physics, and I was able to provide some color commentary for a night of a LOT of fun and learning!
Wow, your parents must be so proud...of your siblings.
@@tekblade how rude
and that is why i try to get seated at the front of the plane.
one question I always failed to answer/understand:
The ship is moving relative to the planet and the planet is moving relative to the ship, depending on the piont of view. Therefor both are efected by the same efects relative to each other.
but why is the ships time moving in slow motion if I watch it from the planet but not the planets time if I watch it from the ship?
Wait. Do I have to compare the speed of each systeme on its own to the speed of light? If so I have several other/new questions.
" why is the ships time moving in slow motion if I watch it from the planet but not the planets time if I watch it from the ship? "
The planets time is also moving in slow motion if you watch it from the ship. Who says that it does not ?
@@silverrahul the fact that you can "time-travel" into the future if you fly at high speeds. If you would slow down from the perspective of the ship both systems times would match up again if you bring them back in sync. But that's not the case.
@@FelanLP No. Why would slowing down the ship bring both systems back in sync? Even if you slow down, if there is any relative velocity , then there will be time dilation, only the magnitude of time dilation will be lesser
@@silverrahul I didn't said that slowing down the ship would bring both systems back in sync.
The slower flow of time is the reasons why the ship is traveling into the future. Less time is past for the crew at the ship compared to the time here in earth.
*But* if this would just be a visual thing and both systems would look slowed down in time if you watch them from the other system, both time dilations would cancel each other out AND you could also observe a "fast forward" time movement on the other system if both systems starting to get back in sync IF time dilation would just be an illusion.
Idk what you mean with different magnitude of time dilation. If I'm moving with 20km/h relative to you, you are also moving with 20km/h relative to me. If we both are effected by time dilation we would both be effected by the 20km/h equivalent of time dilation. But it's not possible that both systems are effected by time dilation relative to each other. We can measure it by sending a clock in a plane around earth and comparing it to another stationary clock after said trip.
It's irrelevant if you were watching the clock from the plane or from the ground. The clock who traveled around earth traveled through less time at the same time the stationary clock did. Even though the stationary clock was traveling the same way, just in the other direction, relative the the clock on the plane.
And that's what my question is about. Why is that so? Why is one system effected by time dilation relative to another, but not the other way around? Is it because of every systems own relative speed compared to the speed of light itself what says his much each system is accepted by time dilation? But if so, what if I slow myself down compared to the speed the earth is traveling through space?
@@FelanLP Different magnitude simply meant that the time dilation would be more at 20 km/hr than if he slowed down to 10 km/hr . They would of course be the same for both the observers at the same relative speed.
" But it's not possible that both systems are effected by time dilation relative to each other. We can measure it by sending a clock in a plane around earth and comparing it to another stationary clock after said trip. "
Both systems are affected by time dilation relative to each other. To be very precise, 2 observers moving IN UNIFORM SPEED past each other will each, in their own frame, have the other observer's clock slow down. The clocks on the plane experiment cannot test this directly because, the clock on the plane cannot be in uniform speed as it has to go into non uniform speed to be able to get back to the other clock
Phenomenal video. I have watched several videos explaining special relativity, but I would rank this the highest in terms of ability to tech and make one understand the concept
The best explanation video of its kind on RUclips!
The background music sounds like GTA V will load any moment
4:33 I didn't quite get why the back of the ship is in the future and the front in the past. Is it related to the acceleration that got the ship to that speed? I can't find a way to visualize it. Magnificent video tho, it's one of the best on SR.
It's a consequence of the constant nature of lightspeed. Since the observer stood in the center and shot both beams of light at the same time, for him, they should strike the ends at the exact instant. But, since the spaceship is moving forward, the only way light can strike both ends at the same instant, is if the time in the back is less than the time in the front, since light has to cover a lesser distance to reach the back end, as speed must be the same.
Watching this guy's videos for free literally feels illegal ngl. great content 😭
Brillant animations! I will share your videos with my Italian friends, nice job!
Grazie Luca !
Why is the rear in the future? This part feels like there is no explanation, otherwise good video
From the outside of the spaceship, the rear seams to be in the future because the light ray reaches it before the front, while the two events were simultaneous inside the spaceship.
ScienceClicEN ooh that makes sense, thanks
@@ScienceClicEN Neither of those are "in the future" any more than the light from a distant lightning strike is "in the future" relative to the sound of the thunder. The spaceship is entirely within the past light cone of the outside observer, but events inside the spaceship reach the earth observer in a different order than they reach the observer in the spaceship. Nobody's seeing the "future" of anything. I consider this to be a serious philosophical mistake that has led to a lot of really unnecessary confusion. There's a difference between a clock ticking faster and a clock being "in the future".
Actually no, the relativity of simultaneity is *not* a visual illusion (like the lightning strike). The spaceship is *not* within the lightcone of the observer, and that's precisely why you can have different slices of simultaneity. When you have two events happening outside your lightcone, the order in which they occur in your frame of reference is not important
@@ScienceClicEN I didn't say it was a "visual illusion", that was just to make my point clear. Special relativity shows that simultaneity is not an objective property, but that has been overstretched to conclude that there is no such thing as the past and future. That's a conclusion drawn from sloppy use of the word "future". There's a fundamental difference between "This thing in the past that happened after another thing in the past that also happened" and "The future relative to me, here, now or you, there, then".
And I would disagree that spaceship is not within the past lightcone of the observer. How on earth am I to observe it if it's not in my past lightcone? Again, this stems from a sloppiness in clarity about who is seeing what when and how they're entitled to divide up the universe. I'm not blaming you, this is absolutely typical of textbook special relativity. Certainly the math works, but the interpretation of special relativity on a conceptual level has gone horribly wrong and led to a bunch of rather obviously silly conclusions.
This is my mind spa, absolutely love it. And for the background track I can listen to this over and over for days
This one video cleared out so many questions of mine. Kudos to the awesome creators!
Why is the rear of the ship is in the future?
Awesome video, great explanation!
This channel is so amazing, I'm going to learn french, just to understand all videos uploaded on the french channel.
Absolutely incredible video, it deserves 10M views at least!
Thank you for this elegant explanation. Thanks to this I’ve got more thirst for knowledge and feel proud of myself.
More beautiful videos like this please.
Crazy stuff! I hope more videos on this come out, as it takes some time to understand... Still, you explained it very well!
Every time I watch a video about such concepts, I genuinely want to cry.
Amazing video, thank you
this channels general relativity video helped me finally understand it after watching so many videos and reading so many book explainations that i thought i would check out their special relativity one and it did not disappoint! thank you!
Great explanation. Close to the end you describe how it is impossible for a mass to travel through space at the speed of light relative to another object because it would require infinite energy. Equally interesting, coming from special relativity, is that if in theory a mass *could* travel the speed of light, it would not experience time passing at all. If sometime in the distant future we could invent an Alcubierre/warp-drive that travels the speed of light, we could eliminate the time passed for passengers, even to distant stars and galaxies. Only problem of course being it would also consequently eliminate meaningful communication and cooperation between those passengers and those who didn't make the journey: hundreds, thousands, or even millions of years may have passed for everyone else, and all of civilization could be different or disappeared altogether, but quite literally in the blink of an eye for the travelers.
Wonderful explanation
Blows my mind every time.
Thank you very very much, this channel is my favorite one! I am chemist and it gives me motivation to study Physics.
Great video, thanks!
I was thinking about the rear and front of the ship being out of sync, when you made me remember the time formula from Lorentz transformations has an "x" in it.
Thanks you gained a new sub
very good explanation
That's a great explanation sir 👍👍👏👏👏👏👏
I have been struggling to understand time dialation, but this video finally made sense to me!
What a great video with explanation. 👍
Wow! this's so educative.. Relativity, the mother of sciences!
Your content is amazing
Salute man! Such an eye opening explanation to an ordinary engineering student. Thank you.
congrats. best video on SR ever seen so far
A question that’s always been stuck on my mind regards SR:
say there is a spaceship on a landing pad on earth. The spaceship blasts off at 99.9% the speed of light.
1. What would an observer on earth see (e.g. the ship instantly zipping, or not moving?);
and 2. What would an observer on the spaceship looking out of the window see?
You’ve explained everything so well but I can’t seem to answer this question. I need to rewatch a few more times :-). Thank you
1. Earth observer would see, the ship instantly zipping
2. Spaceship observer would also see the earth instantly zipping back.
Well the spaceship can't instantaneously gain 99.5%the speed of C. It will be continuous increase in speed. Even though the time it takes could be very small. The observer will see a continuous contraction in length until the speed is constant. For greater acceleration the contraction will be faster for smaller acceleration the contraction will be comparatively slow.
wonderful! This is the video out of so many that explain relativity that I have understood perfectly. Finally I understood the core principle behind how relativity works. It's the principle 'the speed of light is constant' that makes relativity. Even from a moving vehicle, the speed of light doesn't increase like a ball thrown in a vehicle moving at a speed will add up with the speed of vehicle.
but what if the speed of light also adds up with the vehicle speed? then the speed of light increases more. But who made research on it?
why this channel haven't reached 2mil yet?
The best video
Thankyou soooo much man
7.00 is fantastic. Thank you
Best explanation I've ever had🔥
I enjoy these explanations of time dilation and lack of simultaneity, but the problem I have with these examples is they are for macroscopic effects: We and everything are “presumably” quantum, thus everything interacts with the speed of light so locality and spacetime geometry is different for a quantum object. Gravity may be a result of entangled objects. Local interactions like the moving spaceship example means that a signal sent will reach both ends of the spaceship in the same reference frame. A distant quantum object would perceive that signal as delayed from the “front” depending on the direction of motion of the entangled object (in this case a macroscopic spaceship). It would be interesting to map quantum objects in terms of relativity because it makes more sense to me to cancel out macroscopic features like time dilation and gravity and understand the perspective of a quantum object instead.
Great video 👌👌👌
I like your channel very intresting topics that you are talking about
Very well made video
Mind browing explanation 😮😮liked it most 😊😊
It is possible to derive 2 contradictory time dilation equations. The first paragraph below describes the situation with Sally aiming a flashlight straight up and down so that Sally sees the light moving straight up and down and John is outside the spaceship and sees the light forming a triangle with the floor of the spaceship. The second paragraph describes Sally aiming a flashlight towards the left while the spaceship moves to the right. Now the situation is exactly reversed. Sally sees the light forming a triangle with the floor and John sees the light bouncing straight up and down.
Sally is in a moving spaceship. John is outside the spaceship. Sally is moving to the right at .6c. The height of her spaceship is .8 light-seconds. If Sally has a light clock with the light bouncing straight up and down the light will make a 3-4-5 right triangle from the viewpoint of John. If the change in time for Sally is delta T_o and the change in time for John is delta T then the following equation can be derived: delta T = delta T_o/((1-.6^2)^.5). So .8 seconds for Sally = 1 second for John.
Now Sally has a light clock but this time she is holding a flashlight at an angle of 53.13 degrees above the horizontal and pointed to the left. Now the leftward movement of the light exactly matches the rightward movement of the spaceship from John's viewpoint. Now the light is bouncing straight up and down from the viewpoint of John and the light is making a 3-4-5 right triangle from viewpoint of Sally. If the change in time for Sally is delta T_o and the change in time for John is delta T then the following equation can be derived: delta T_o = delta T/((1-.6^2)^.5). So 1 second for Sally = 0.8 seconds for John. The 2 equations are in direct contradiction to each other.
Special relativity is falsified.
Superb,
Only now I can exactly learn both special and general relativity principles👍🏻
Hello, congratulations for your videos! I wonder if it would be possible to arrange a series dedicated to the Maths of Special Relativity? Thank you so much!
Sometimes I have this question like you said about the example of the passenger in the space ship but how can one look at two different directions at the same time. But the example given by Einstein of a passenger in a train in that example it's about the effects of two thunderbolt like light and sound. So in this case is it about the reflection of light? I don't know.
Awesome videos
Subscribed to your channel 👌👌👌
best science teacher to date
Hmm... I think I grasp the concept now. Since the speed of light is a unbreakable and fundamental law of physics, the lights on the space ship must reach the ends at the same time (if you are on the space ship) because it would be you that are stationary and the planet is moving backwards.
However, if you observe the ship on the planet, the front light cannot reach the front end of the ship first because the ship is moving forward (relative to the planet) and that would mean it would have to break the speed of light in order for that to happen. So in order for the speed of light to remain the same, time must change when observed at a distance..
This seems a correct explanation
I've read this in a book called Space Time and Einstein, but was having hard time visualising it
Thanks a lot
Binge watching all ur content.
this channel is too much underrated..
Best explanation of SR!
Why is the rear of the ship is in the future? u can't say. Therefore I don't think it's a very good explanation
Best of best explanation