What is time dilation : evidence behind it - muons and clocks and planes.

[@elonximperator892]

*Finally I now understand Time dilation in this video.* I watched many different videos to understand this topic but they were unable to explain this accurately and precisely! Thanks😀😀👍

[@PhysicsHigh]

You’re welcome.

[@alexanderevans8524]

I think its mad. I want to disprove it.

[@alexanderevans8524]

@@frankdimeglio8216 that's some circular reasoning friend. Everything is as it always has been, what it was. Therefore being, is as it was when it wasnt as is. That's about what I got from that. Your sighting that electromagnetic energy is causing gravity. So electro magnets are essentially gravity fields that only effect metal?

[@Jz2727]

@@alexanderevans8524 Don't indulge in his blabber

[@PhongNguyen-tp7lg]

so do i

[@natharistaats]

Finally I found the best place for a clear explanation. Your explanation is now clear as a crystal to me !!! Thank you 😍 I watched 100 of video to understand this but it was a waste of time. And thanks to you PhysicsHigh I have got this wonderfully..

[@ezdeezytube]

At 12:50 it is mentioned that the "fixed" spot on the surface of the earth is "fixed" in a frame, yet also the earth is rotating and travelling through space. This seems contradictory. How did they compensate for the speed due to rotation of the earth at ~1000 mph, revolution of the earth at 66,660 mph, sun around the galaxy at nearly 500,000 mph, and Milky Way through space at over 1,000,000 an hour, to say that the planes were moving faster over time than the "stationary" base?

[@YourDailyDoseofContent]

Has the list of potential expeiments validating einsteins special relativity been taken down?

[@MontyVideo969]

I'm struggling. The description of the experiment with the 747 flying around the World both ways doesn't make sense to me. It suggests that all that has been proved is the case when a "light based" clock is being used - which I understand - however that's just proving Pythagoras. What if a mechanical clock, (one with a hair spring for example) was used and the aircraft flew a million times around the Earth (so a reasonable measurement could be seen)? My confusion stems from using a "light clock" that uses distance to measure time. Clearly in the diagram, the clock isn't the same when it's moving because the distance between the transmitter and the receiver changes, but "real time" plods on regardless.

[@dleddy14]

Why are t and t0 not interchangeable? What if Einstein were in the train looking out the window as I did the torch experiment on the side of the track? In that case wouldn't my time be measured as smaller than his time given that the light will have traveled a greater distance from his frame of reference?

[@FisicaDirectoaoAssunto]

You sir have helped me cross the Special Relativity bridge with relative ease! Thank you so much I was going bonkers😂 Not understanding how time factos in a Pitagorean diagram with distances but as part of a product of time-space it all makes sense.

[@PhysicsHigh]

Great. Glad I could be of service.

[@OttoNomicus]

Only problem is, when you showed the flashlight beam on the train it wouldn't really travel on a slanted path like that. That's the path a rubber ball would travel, because it's a physical object and therefore has inertia. What would really happen is that the photons would travel straight up from the point at which they left the flashlight. The person on the train would see it slanted backward (to the left on the screen). This means that he could actually tell that he was moving, if he was moving close to the speed of light. If my theory is correct, to shine a light bean straight up you would have to point the flashlight on a slant toward the direction of travel.

[@ianthompson4882]

Einstein would disagree with you! Einstein's starting point was that there is no experiment you can do to determine your absolute velocity. If your explanation was correct, then the guy on the train COULD determine his absolute velocity by measuring the angle of the light. This violates the "principle of relativity", so it must be ruled out. So, according to this postulate, from the train's frame of reference, the light would indeed go straight up at 3x10^8 m/s. But from the ground's frame of reference, the light goes on an angle, as shown in the animation, but also at 3x10^8 m/s. So if the laws of physics work for both frames of reference (specifically, speed = distance/time) and the speed of light is the same from both frames of reference, but the distance travelled from each frame of reference is different, the only logical conclusion Einstein could make is that the measurement of time is different from each frame of reference. That is, the measurement of time is relative to the observer's frame of reference.

[@maddoxmazlan4184]

Awesome explanation, could get no understanding from Wikipedia.

[@PhysicsHigh]

Thanks.

[@rogerg4916]

In the Hafele Keating Experiment the earthbound clock, the atmosphere and the airplane are all moving with the rotation of the earth so that motion is irrelevant. All that matters is the speed of the airplane relative to the earthbound clock. But this is the same whether the airplane is going east or west (or north or south). So why is time dilation not the same for all directions?

[@voidisyinyangvoidisyinyang885]

the atomic clocks are the references frames so the time that is relative is the speed of earth plus the direction of the plane (either with earth or against earth). the atomic clock is based on the frequency of light so does not change relative to its location in space. With Caesium, what is measured is the frequency of the radiation emitted when it transitions between two hyperfine states. The frequency of this radiation is dependent on the energy difference between the states which is fixed and not dependent on any variables external to the atom. It is that frequency that defines the second. The second is the same for GPS satellites as it is here on Earth. But, because of its position and speed, more time actually passes for it than does for us.

[@stevemuller8320]

the eartbound clock is moving too - plane_east, earth_station, plane_west - all are moving in relation to the unmoving center of the earth. (even the height of the planes cause an effect in SRT - and additionally an effect according to ART (gravitation)

[@RoyBatham]

The Hafele Keating Experiment is not valid. It's an experiment with CLOCKS not Time

[@Tzadokite]

according to the Einstein-Lorentz transformations and STR paper from 1905, the time dilation is given by, t(v) = t(0)*(1-v^2/c^2)^1/2 and not as shown. also, the Time Dilation equation, of the Lorentz-Einstein transformations, is a purely kinematical equation. if we apply it to the cosmic muon as shown, then we must assume that the Earth is moving at -0.998c relative to the muon. however, this would be a violation of the conservation of linear momentum for the Earth-Muon system. for the earth-muon system we have M(earth)*v(earth) = -m(muon)*v(muon). hence, v(earth)= -(m/M) * 0.998c. this is not equal to v(earth) = -0.998c. in fact the v(earth) is essentially 0. we cannot use v(earth) = -v(muon) = 0.998c in order to apply the time dilation equation. we have to use gravitational time dilation which is insignificant given the GF of the earth to increase the decay time of the cosmic muon to reach the earth surface.

[@haddow777]

What I've never been able to understand is why, with the experiment where the light is moving up and down with the sideways force of motion, they would think the light would move sideways as well? We know the speed of light is a constant and cannot have speeds from vehicles added to it. We know that when we look at the stars in the sky, we aren't seeing where the stars are, but where they were when they emitted the light. Same with the moons of Jupitor. Yet, somehow this light beam going perpendicular to the moving box is somehow moving sideways so it appears to an outside person it's traveling in a triangular fashion. If it acted like the starts, is woulf bend back and fall out the back of the box as it headed to the ceiling. That is, if the train was moving so fast that the box would travel that far sideways before the light could reach the top. That sort of triangular motion of light comes from the Aether days, when the Mickelson-Moorely experiment tested if the Aether caused light to travel a longer distance when fighting through a cross current. Pretty sure it proved it didn't do that.

[@AMC2283]

The velocity of light hasn’t changed, it’s bouncing off mirrors in relative motion

[@manipulativer]

oy You said there would be more experiments in the description but there aint any

[@xandermoore8419]

SOMEONE EXPLAIN THIS TO ME. If you did the mirror experiment, wouldn't the light just fall behind the mirror. it has nothing to hold onto so it wouldn't stay in the middle it would slowly fall behind. Also, if it did stay in the middle of the mirror this would mean its traveling faster then the speed of light, but the speed of light is supposed to be constant. It either falls off the mirror, or gets pushed forward by the train making it faster then the speed of light. Either way it doesn't make sense. i'm not saying Einstein was wrong but this is not proving him right.

[@ThePsychorella]

If you are travelling on a train, airplane or any other vehicle and jump straight up, would you also fall behind? Or if you try and throw a ball straight up, where does the ball fly? Answer for both cases is that both you and ball would go straight up and straight down, no falling back. Same thing happens with that light beam, it travels with the mirror and won't fall behind it. "Also, if it did stay in the middle of the mirror this would mean its traveling faster then the speed of light, but the speed of light is supposed to be constant" Here comes the time dilation. Light would indeed travel a longer distance and IF time would be static and same for everyone, there would be a problem, cause as you said light would travel faster than speed of light. But because speed of light must stay constant for every observer, time can't be same for everyone. Thus stationary observer sees that time slow down for the moving observer. That fixes speed of light, distance gets longer but time interval gets smaller and c stays constant. I hope this clarifys the case.

[@xandermoore8419]

​@@ThePsychorella Thank you! That was the best explanation I've seen.

[@Mk101T]

@@ThePsychorella But wait a minute. Suppose this scenario ... You are traveling in a train at the speed of light , and at 5 light seconds away from a wall at the end of the tracks. You flip on your lights which just so happens you pass an observer. Which I assume will not see the wall lit up at all , just you crash into it ? The question is ... will you see the wall lit up , and at what second interval ? Oh ya , I guess it's a train on flat earth since curvature would cause problems with line of sight. Err heck why not a space train , since we need one of those for getting to the moon anyways ;)

[@ryan-cole]

Great video. Subscribed.

[@PhysicsHigh]

Thankyou. !

[@hosh1313]

Muons are just as easily explained by length contraction. There are no inertial FOR in the HK experiment - it is very dodgy! All the motions are along circular paths.

[@alexanderevans8524]

So momentum dilates but not when it's a light particle, then time itself bends around the particle? Are you nuts?

[@yankeedoodle8749]

question about the muon. So, to the muon it still decayed in it's "rest" decay time. It only tool longer in our reference frame because its decay happened in its reference frame while it was moving extremely fast, and that's why we perceived it traveled for both more time and greater distance than expected from its rest decay time. Would it work out that the muon also still 'thought' it traveled the regular decay time distance instead of what we observed because at high speed it would also 'experience' length contraction?

[@AMC2283]

It would think it traveled further, faster. If you travel to alpha Centauri at near light speed it’ll seem like you traveled ftl even though it took no less than 4 years

[@dexter8705]

We're never gonna get time dilation right until they add the space dilation and do the equations relative to space and not other objects, object to object should be a secondary equation that has nothing to do with the first then you can deduct the difference to work out the different time rates between them.

[@richardlinsley-hood7149]

1. We have the o1 frame, with the observer standing in the center/origin of the train1 2. We have the o2 frame, with the observer standing in the center/origin of the train2 3. We have the o3 frame or rest frame, with the observer standing in the center/origin and where both o1 and o2 are moving in opposite directions with speed v 4. In each of the 3 frames, at t=0 , o1, o2 and o3 are crossing past each other 5. Train1 has front1 and tail1. Train2 has front2 and tail2 6. There are various points in the rest frame opposite front1, front2, tail1 and tail2 at t=0 7. Light from o1 and o2 will reach their respective front and tail at E2train1, E2train2, E3train1 and E3train2 8. The distances in the rest frame will be the same to E2train1 and E2train2 as will the distances in the rest frame to E3train1 and E3train2 9. The times in frame1 that E2train1 and E3train1 occur will be the same 10. The times in frame2 that E2train2 and E3train2 occur will be the same 11. The times in the rest frame that E2train1 and E2train2 occur will be the same 12. The times in the rest frame that E3train1 and E3train2 occur will be the same 13. Although there is a relative velocity between o1 and o2 as seen from o3 there are no differences in distance (8) or time (11, 12) to the events E2train1 and E2train2, E3train1 and E3train2 as seen from the rest frame 14. If m1 is the mass of train1 and m2 is the mass of train2 and are equal then m1=m2 15. The rest frame can be considered to be the same as a center-of-mass (COM) frame 16. If force F is applied to m1 in frame1 and force F is applied to m2 in frame2, the accelerations of m1 and m2 in the rest frame will be identical 17. In the rest frame, the clocks in frame1 and frame2 tick at the same rate. 18. Spacetime of E1 is ({d, +ve}, t) in frame1 and the spacetime of E2 is ({d, -ve}, t) in frame2. 19. Spacetime of E1 is ({d, +ve}, t) and the spacetime of E2 is ({d, -ve}, t), both in the rest frame 20. E2train1 and E3train1, E2train2 and E3train2 are examples of the paired events, E1 and E2, discussed above

[@hosh1313]

GR says that time passes more slowly when in a stronger G field? Anyone seen the formula for a pendulum? Houston, we have a problem!

[@aresjoel8720]

The little concern I have with the though experiment (between 1’55-2’20) is why do we assume that the stationary observer would see the same photo that Einstein is shooting at the mirror in the roof of the train? There are probably better experiments proving Einstein theory is right but have my doubt trying to prove with this thought experiment. Einstein shooting at the mirror at the ceiling of the train, the observer will not see the light please. Unless the photo shoot at the mirror radiate in multiple directions which is not the case with the photon.

[@PhysicsHigh]

The though experiment is a misnomer, it's not an experiment validating the SR, rather, its a model trying to demonstrate the consequences of the constancy of the speed of light. So yes, I agree with you. The whole 'experiment is not actually doable. Having said that, there are many experiment that DO validate SR, and I mention two of them in the video

[@user-bx7nw1ve6y]

What's a 'though' experiment?

[@PhysicsHigh]

Mistype. Thought.

[@jonathanlichtenberg1900]

If the plane's speed was recorded could it be calculated how fast you would need to go to experience a predicted amount of time dilation?

[@jasoncassidy492]

It is super-easy to defeat the logic in this video. The proof is based on Einstein shining a light vertically. That is real, it is happening. When we view it from a stationary position, and the vertical action turns into a diagonal line, that is an illusion. The human eye and mind lacks the ability to follow the vertical action of the vertical light beam and it appears to move diagonally rather than vertically. The following equation with the right angle triangle from which time dilation is drawn, has two major problems. One, the hypotenuse is based on an illusion and cannot be real. Two, time has no existence. It is derived by humans and is based on the rotational period of the Earth. Ergo, if time dilates, the angular velocity of the Earth must change. Einstein should have known this but he allowed himself to be drawn into an illusion about time. The inventor of the atomic clock, Louis Essen, pointed out that Einstein's theory is not even a proper theory, but a collection of thought experiments. Had Einstein based his theory properly on mass and the force that produces acceleration, he may have gotten that. However, he dealt in kinematic, treating acceleration and time as inependent entities. Major mistake. The Muons prove nothing. Time has nothing to do with their motion. Same with the Twin Paradox, humans don't age based on time, they age due to biological processes.

[@viewer3091]

Is Matter and Gravity = Anti Space-Time ?

[@kenhoffman5363]

Einstein's Special Relativity (SR) is about constant velocity, not acceleration. One reference frame B is moving at a constant velocity according to A who is his own Inertial reference Frame which is also not accelerating . A concludes that B's time has slowed down ONLY because, according to Einstein's 2nd postulate requirement of SR, the speed of light must be assumed to be constant at 'c'. Time dilation is the forced incorrect conclusion of SR due to that postulate. In the "confirming" experiments for time dilation, entering the picture are vectors for acceleration and gravity which could effect internal, kinetic, potential energies. All of which one could reasonably expect might have an affect on the muons half-life from any frame of reference.

[@sergeantblake2344]

very nice video

[@JayZoop]

Light can be distorted, so observing light is a record of what did happen, not what is happing at this moment.

[@PhysicsHigh]

Yes. And I made a video on this point Time Dilation is not what you think it is. kzbin.info/www/bejne/mX26cod9e7BmpLM

[@kimsahl8555]

2. postulate: The velocity c is constant in the "stationary" system.

[@RoyBatham]

Please define your stationary system.

[@kimsahl8555]

@@RoyBatham The postulate 2 is "The velocity of light c is constant to the "stationary" system", (the "stationary" system is stationary to the "stationary" system) The postulate 1 is "All inertial systems is equal". - So it is in special relativity, but the two postulate is't correct.

[@RoyBatham]

@@kimsahl8555 Yeah!,yeah! yeah!. If you like.

[@shoutitallloud]

I wonder do you even have assurance of understanding what are explaining? You state that the FASTER body moves, the SLOWER it's time ticks. Then you calculate muons time and your numbers show just the opposite: 2.2msec passed at rest = 8.2 msec passed at lightspeed muons. And right after, you appeal to planes experiment and get the ooposite again: Moving clock count time is LESS than resting clock. Do you ever had sense?

[@Ninan_9]

Could I get your definition of flux?

[@PhysicsHigh]

Flux has varied meaning in a variety of contexts. In general it can be considered rate if flow in a given area as Is the case of the muons in this video. But flux can also mean number of lines of force , as is the case with electric flux or magnetic flux

[@hosh1313]

I have 2 clocks together and synced. I move them apart in a completely mirror image of each other and then bring them to rest at a distance, again, in a mirror image way, and they both stop running and show their final values. i.e. all accelerations, decelerations and constant velocities happen at exactly the same time and for the same duration in opposite directions. Relativity says one must be slower and the other advanced - but which one is which? From the frame of reference of the starting point, both dilated identically and are thus still perfectly synced? From the frame of reference of either clock however, the other clock is slower? Hmmmm................

[@JayZoop]

I question this whole theory too, but maybe one watch is going with the rotation of the earth, and the other is going against the rotation of the earth. Maybe the experiment should be done with them moving in the north to south direction.

[@RoyBatham]

Relativity is crap,

[@ahmetgazi5624]

This explanation has an undefendable flaw. The mistake is at short side called c*to. Light is a wave not a particle. What reaches the mirror is not a particle, thus we cannot call it c*t0. What reaches the mirror is the wavetip of the wave created at time=0. The distance is t0*c*sinus of the small angle. Time dilation exists only in warped spacetime ( I respect general relativity) not in referential frames. Until today, twin paradox could not be explained without tweaks and 6th degree formulii,etc just to defend Einsteing dogmatically. Science is must be done with beginner's mind.

[@jimhunt2283]

Some people object because they think both planes are travelling away at speed from the "fixed" Earth clock and therefore both plane clocks should read slow. My understanding is that you are only allowed to apply SR from an inertial fame - you can apply it *to* something in an accelerating frame but not *from* an accelerating frame. Therefore the centre of the Earth (or the North pole) is used as a non rotating and hence inertial frame and the calculations based on if an imaginary master clock was there and the non inertial "stationary" surface clock is thus treated as moving. Now, the centre of the Earth is not an inertial frame because the Earth is orbiting the sun and is therefore accelerating. Also, the sun is orbiting the centre of the galaxy, and the galaxy is probably orbiting the cluster and super cluster etc etc etc. But I guess we either give up or let some of those things go by putting error margins in place.

[@dexter8705]

It's funny how the world confuses time dilation with the flow of space.

[@RoyBatham]

It's funny how people think space is flowing.

[@joellereynolds2176]

At the end of calculation did you mean 8.18 microseconds for the half life or average lifetime?

[@danielwheeler8173]

Thank you so much, really useful and clear visual understanding of time dilation!

[@Mk101T]

So a gravity body rotating gives an assist to slowing time if traveling the same direction of rotation. As if mass has gravity fingers that stretch out , and then follow it's rotation. Hence it would be like a tail wind adding to actual speed ( not relative speed) So hypothetically you could slow time to a stand still maybe even turn it back traveling fast enough around the gravity body. (Star Trek IV) But has any physicist bothered to wonder what would happen when you exceed the speed of the rotating body ? Because the experiment showed traveling against the rotation created drag (sped time) Also diminishing return curves are a part of life. Hence a high probability that no matter how fast you travel around a gravity body , you may never stop time , let alone turn it back wards.

[@JayZoop]

You can't actually observe something real time, because it takes time for light to get from the object to your eye / sensor.

[@PhysicsHigh]

Yes and I made a follow up video on this very issue

[@garyrolen8764]

I believe there's a fatal flaw in the ideas presented here. An equivocation fallacy. The fallacy occurs in the understanding of "frames of reference". Light is measured as c in all frames of reference might be the case. This is firstly just an assumption. But secondly it becomes fallacious when we misuse the words "frames of reference" to describe two separate observers measuring the same light.

[@garyrolen8764]

There's a second fallacy occuring in your thought experiment where the observer on the train sees the light travel up and you see the light travel at an angle. Circular reasoning. You presume time dilation to use this thought experiment to prove time dilation.

[@garyrolen8764]

The problem with the thought experiment is with the travelers perceived measurement of the distance the light traveled. He may not feel motion, but the motion still exists. The distance the light traveled is the distance the light traveled regardless of perception.

[@garyrolen8764]

Another problem with the thought experiment, goes back to my first comment, he measured the light, you didn't. In fact you can't. You're assuming the distance traveled, not measuring it. You can't measure it. That's not how photons work.

[@garyrolen8764]

At 6:59 you finish up making a very bold assertion. We have nothing but the math to suggest the effects of traveling near light speed. That math is not evidence of this particular claim. So, when you say we're going to see this, we're not. Not here in this video and not likely ever, but maybe, hopefully one day we can figure out a functioning hyper drive.

[@garyrolen8764]

The muons... Perhaps, but again you're presuming too much.

[@SciHeartJourney]

Time dilation IS real! They've verified it over and over again. Basically, any motion in 3D space takes away from our "motion in TIME". Pretend you're walking due north at 3 mph. All of your motion is northbound. Now imagine you veered off a bit, but your still going 3 mph. However, the northbound component of your motion is no longer 3 mph. Now realize that your northbound motion is your motion through time; 3 mph is the velocity 'c'. We're all travelling at 'c', the speed of TIME, ALL of the time. Any motion in 3D space takes you off that path, making the journey longer. That's the best explanation I've heard to explain how time dilation works. I hope it helps the curious who might read this.

[@chaloesalagon7721]

well isnt that because the distance has increased from one point to your destination because you veered a bit? isnt time dilation only possible if one object moves in the speed of light because the speed of light is constant and never relative? and so the time "compensates" for it, making 2 different possible frame references? if your statement is true, someone who is at the destination must start a stopwatch from when you fled and stop it when you reach the destination and you do the same thing, by the time you reach your destination would you notice that the numbers are the same? well that wouldnt be the case if it were time actually dilated, because if time actually slowed down for you then your numbers would have been less than someone who is in your point of view "stationary"? correct me if i am wrong please the idea is just new to me and this has caused me confusion.

[@kyle1562]

@@chaloesalagon7721 yes. Time dilation is just a perception

[@new-knowledge8040]

If you dropped out of high school, and so this stuff seems complicated, you can always take the easier approach. Simply discover the special relativity(SR) phenomena by yourself. All you have to do is analyze "Motion" to determine what it is, and what it is that is required to make motion possible. And bingo, the job is soon done. At the same time, you will have derived the SR mathematical equations, including deriving the Lorentz transformation equations. If you watch my YT videos, you will see how a high school dropout that had no physics education at all, can complete the task.

[@andrewbodor4891]

Matter and dark matter: Galaxies rotate too fast but are not torn apart. What causes galaxies from flying apart? By Csaba A. Bodor. Last edited April 4, 2022 gravity, they say, is associated with baryonic matter and with dark matter. EVEN better: gravity is associated with the mass of baryonic matter and the SPEED of motion of the former. Dark matter gravity is caused by ordinary baryonic matter in motion! Some speculate that a mysterious substance called "dark matter" must exist which holds the galaxies together. I submit that this dark matter is nothing more than ordinary matter which is in motion around the galactic core and around the billions of stars. Matter that is in motion presses against the aether of space (to those stuck in the Einstein loop, it is also called space-time) and the aether presses back in the form of gravity and the moving matter also creates time dilation. This gravity could be the missing gravity that is holding galaxies together. There are two types of time dilation. One is caused by the aether's affect on matter and the other is the aether's affect on speeding matter or electromagnetic "waves". As matter, of any size, displaces the aether, the aether presses back with what we call gravity. This gravity presses on the matter affecting it's "being". All activity of matter os slowed down. The cesium in a cesium clock runs slower because the nuclear particles of cesium are slowed down. The clock therefore runs slower. Radioactive elements all run slower; their half-lifes are increased. Their internal subatomic particles run slower. The microprocessors and other perts of computers all run slower. Our brains are affected also and our minds work slower. Everything near and about that matter that intruded into the realm that belongs to the aether runs slower. As one moves away from the mass of that large mass we live on the press of the aether becomes less and the particles and pieces of the atoms will run faster since the gravity created by the aether slowly lessons as we move away from the large mass. That cesium clock runs faster. The half-life of the radioactive elements changes and its "time" is affected. Humans living further from the mass of the earth will perceive time as running faster. Computers will likewise run faster. Time dilation that is caused by motion comes about because of the motion of matter or electromagnetic waves through the aether. A photon traveling at "C" pushes against the aether, the aether pushes back and creates gravity. The internal properties of the photon or even matter are slowed down. As humans move through the aether at great speeds we perceive the time runs slower for us. Time dilation. For a photon, because it is traveling at "C", time actually stops. The photon experiences NO time. The photon cannot travel faster than "C" because the aether sets the speed limit by pushing against the photon's motion through the aether. This is also why matter cannot go faster than "C". When light goes through a gas or a liquid it is forced to slow down and give part of its energy to the gas or liquid which eats into the photon's ability to move at "C". The energy given up heats up the gas or liquid or can even affect the atom's motion; even give off its own "light". We do not see a photon as it travels through the aether. When the photon or other electromagnetic wave hits matter, it slows down and even stops. As the photon does this the photon's energy turns into visible light. PS: Dark matter gravity and dark energy is nothing more than the gravity created by the matter inside a galaxy moving about, pressing against the aether, and then the aether presses back with gravity caused by that motion. All the electromagnetic waves (photons) bouncing around the galaxy also add to the missing gravity that some say is caused by dark matter. Nothing dark (unknown) about it. Look to the movement of matter and electromagnetic waves (including photons).

[@johnWick-lu3ev]

im not a genius or anything but the way i see it if you travel at speed of light away from earth the earth will look slow or fixed in time and if you travel faster than light the earth will look going back in time let's just say you travel 10 light years away and look back at earth the earth you are looking back are 10 years ago if you travel back to earth at the speed of light the earth will look like in fast forward and look like you are traveling forward in time.

[@lawrence1318]

Time Dilation and Relativity are bogus, being based on a geometric contradiction and the fallacy that the speed of light is the same for all observers.

[@spaceadventurer100b8]

Great video, thanks. I’ve seen the equation written two ways. t = t’ x root 1-(v^2/c^2) Where there is multiplication in the equation and t’ = t / root 1-(v^2/c^2) Where there is division in the equation. Which one do I use and do these relate to what answer the question requires?

[@levisbrat1147]

I know that my reply is late but the second equation is correct but in the first equation it should be t(1+v²/(2c²)) I guess .(using binomial expansion in second equation since the power is less than 1 )

[@Gertzy41]

If travelling at the 99% speed of light, and you put a frozen dinner in the microwave would it take 2 hours to heat up ?

[@Mk101T]

Not sure about the exact speed , but If the micro wave was stationary , and you flew around it. Yes by your time. If the micro wave is on board your vessel then it would heat it in the normal time to you. At least in theory . Hard to say if the micro waves would be effected by your speed though.

[@yankeedoodle8749]

I think you would have to be "stationary" and the microwave with your diner in it travelling at 99%C for you to think it took two hours. But shooting your microwave off at time dilation speeds kind of defeats the purpose of using a microwave in the first place, doesn't it? :)

[@Fjord19873]

Good explanation. I really like it. The problem I see is that what we measure time indirectly. We measure how many events happen, believing that the time between two events is the same. But here lies the problem. what if the time between the two events is not the same? Perhaps the time between events can be different because things (more correctly: 'being' or in german 'sein', in french être) consume time. Mass then would not really exist, instead the opposite would exist: gaps in space and gaps in time in which both go out of existence in the universe. Gaps that move ofcourse consume more space and time. Gaps that are in close proximity to other gaps will consume less because the other gaps consume too. If the others eat a lot then I can eat less.

[@scullnbonesent]

Lost me at t …. Damn wish I could comprehend math

[@yankeedoodle8749]

Ok big prize to whoever can answer this. We're all familiar with "time slow down" the faster you go. So if a rocket blasts off from earth and travels very fast time slows down for the rocket compared to earth. But what if the earth was moving in a cosmic current to begin with, and the rocket took off against that cosmic current resulting in the rocket actually achieving "cosmic motionlessness". Everyone on earth would still think that time on the rocket was slower compared to earth. How can this be when the rocket has actually no velocity while the earth has all the velocity drifting along in the cosmic current? If everything travels "at the speed of light" through space time, and the rocket is motionless, then all it's "speed" is being used to travel through time. It has max speed speed through time. So how can those on earth calculate that they are moving through time even faster?

[@liquidphilosopher1816]

"So if a rocket blasts off from earth and travels very fast time slows down" First explain: Why would the time actually slow down? Why do you believe that?

[@Gertzy41]

If you're traveling at 99% the speed of light and you watch a video 3hours of the godfather , would it take 21hours to watch it????

[@PhysicsHigh]

If you are watching the movie in your frame of reference, then it will still be 3 hours. If you are watching the movie outside your reference, then yes, 21+ hours !

[@yankeedoodle8749]

@@PhysicsHigh Now explain how you could watch the movie outside your reference. ;) With a pair of very good variable magnification binoculars? ;)

[@talesara74]

To make it even more interesting : 2 spacecraft travelling towarss each other at speed of .7 c. So both are at speed of c relative to each other. They both would need infinite time to watch movie!!!!! This is where this whole thing become a finction.

[@voidisyinyangvoidisyinyang885]

@@yankeedoodle8749 the same way we watch Dr. Who episodes

[@y0uCantHandle]

Ive recently read a paper that says differential time dilation (as a result of mass causing curvature) is the critical component in causing gravity, not space being bent. Do you have an opinion on this? iopscience.iop.org/article/10.1088/1361-6552/ab56d7#pedab56d7bib016

[@PhysicsHigh]

Up have a read. I know one of the authors and she is a first rate scientist. I’ll get back to you. In the meantime Ill also forward to Geraint Lewis, professor of cosmology at USyd who might also chime in.

[@y0uCantHandle]

@@PhysicsHigh Ive since gleaned from others that its a result of space time being interlinked. Im sure this is a bad summary but here goes: As space-time warps or condenses, a body will experience a space-time differential. Essentially General relativity says that ΔV * ΔT must

[@shoutitallloud]

I don't know how anyone can agree and reasonably be sure in that nonsense

[@keith.anthony.infinity.h]

Says the one who is using a piece of technology dependent on satellites which take into account time dilation?

[@shoutitallloud]

@@keith.anthony.infinity.h Are you exactly sure they are using calculation with time dilation? They just keep correcting clocks constatnly.

[@keith.anthony.infinity.h]

@@shoutitallloud Yes they are using time dilation which is an idea of Albert Einstein. How do you think people correct clock measurements even though they are fixed and repaired up to date. The satellites in space should be off about 7 microseconds compared to satellites on the ground.

[@shoutitallloud]

@@keith.anthony.infinity.h it's just the time difference for signal to travel from sattelite to earth

[@keith.anthony.infinity.h]

@@shoutitallloud Haha exactly and what do you think the satellite signal is? It is light that is either redshifted or blue shifted in wavelength but the speed of the wave is constant which is the speed of light, or “c”. When this redshift or blueshift happens time ticks differently as the satellite moves at a certain velocity whether you use an atomic clock, a light clock, or any other time-measuring tool.

[@timefactortheoryofgravitya7578]

For more mind boggling facts about Time Dilation: Time Factor Theory.

[@qwantron22]

People getting their "facts" from theories is the problem. True science is dead, scientism pushing shills killed it.

[@cliptracer8980]

I'm sorry. You gain an f. I reacted. Please consider. Light has to keep up with your speed. You go faster you move the target.

[@SciHeartJourney]

If v > c, then the value becomes an "imaginary number", just like the imaginary spaceships we see in movies.

[@ujjwalbhattarai8670]

Time dilation is wrong concept. It not exist. Imagine twince brothers one is running with speed of light having same mass in stadium and another is watching over a year. Now thing will change for both after a year ? One be older than another ? Thing will change for both and twice see differently? Sun rises as sets differently for both? Weather change differently? Yes time dilation is 100% wrong concept. Watch/clock( artificial machine ) stopped so time dilation is exist? That's stupid. idea completely stupid concept. One should travel space more than for experience time dilation? Nothing is more stupid idea than anything else. Time dilation is wrong concept 100% wrong. Sorry respect sir. Time dilation is wrong concept.