NASA | Einstein's Cosmic Speed Limit

[@NASAGoddard]

The other telescope referenced was Magic, a ground-based observatory. The delay it saw could have been caused by a number of things: photons leaving at different times, interference with the earth's atmosphere, etc. Only a space-based telescope like Fermi, looking at an instantaneous event, like a gamma-ray burst, could eliminate those two variables specifically, allowing researchers to arrive at the conclusion that space-time is not foamy enough to interfere with the speed of light.

[@NASAGoddard]

Actually, his theory of special relativity says that all objects should travel at the same speed relative to each other, including differently energized light particles that just so happen to be traveling at the speed of light.

[@sabiki74]

The reason the lower energy arrives first is that it actually traveled a shorter distance. The higher energy that was measured was warped around some mass in the space time fabric.

[@lightingrings]

No, they had an error with the lab setup that recorded it to be bit faster than speed of light, however after fixing the error that was no longer standing.

[@NASAGoddard]

If you like to learn more about this, look-up the article "Late light reveals what space is made of " in New Scientist magazine (written before the Fermi discovery), or read the Fermi paper this film was based on in Nature magazine (search for "speed of light"). I'm including the links in the synopsis above, as KZbin won't allow me to post them in the comments sections.

[@FlavoredCoffeeGuy]

Do the math for elastic collisions in this situation, you have 10 cue balls on either side of a pool table, and the peak speed limit of any one cue ball is 3 MPH. You are never allowed to strike the cue ball from directly behind, you only get to nick the 8 ball once, with all ten cue balls. Fields do not produce more or a different collision, so super colliders are no clue. Until the energy of a given laser exceeds the E=mc^2 per unit volume, the nucleus of the atom, you can't hit it directly

[@FlavoredCoffeeGuy]

1/3rd light speed, the size of the electron, is small enough to slip into the negative value of time, and put the electron in two places at one time, and it can interfere with itself.

[@StereoSpace]

I think they were talking about the "texture" of space at the quantum mechanical level, which says that at a very, very small scale space-time is like a seething foam - hence the bubble wrap analogy. Whereas, relativity theory says that when viewed from a very large scale space-time is smooth. The question being asked is, How does this affect the speed of different energy/wavelength photons over long periods of time? The answer is that photons see space-time as smooth.

[@aseeruzzaman9671]

The light could have gone through an optically denser transparent medium before reaching us and because the speed of different light waves is different in other media, it could have changed. And that makes sense because radio waves were faster and reached earlier than the gamma rays that happens in an an optically denser medium. But hard to say which transparent thing that might be.

[@shahrulconstitutional261]

EINSTEIN STILL A KING OF GRAVITY. Many newer scientists proudly said they know General Relativity or Gravity more than Einstein. The truth is Einstein knew what Gravity truely is, inside and outside, and nobody will come near to his understanding of gravity. If he is still alive, more knowledge on Gravity will come out and some are very surprising and paradigm shifted.

[@kronahwood5271]

If the light isn't measured until it hits the device, you have to have multiple measuring instruments in the same device and in another device in a different gravitational location with multiple measuring instruments to get a better understanding of the difference of time in gravity by different particles traveling great distances both with heavy gravitional difference and light gravitional difference.

[@seahyimin]

i really respect nasa's way of reaching out to amateur science enthusiasts

[@FlavoredCoffeeGuy]

If space time was foamy, it would be a very fine foam. This foam and the potential of positive and negative values of time would explain everything with the double slit experiments. It just says that the electron is small enough and fast enough to be in two places at one time. Solids, bodies, mass, your sensor, consolidates and average rate of the passage time. So, when the sensors are not there evening out time in passage, average time includes both negative and positive values.

[@AboutHreinzi]

i think its amazing how far we are heading into the space exploration business and one day maybe not in my life time we can finally go to others stars and become one galaxy race of humans who goal is to gain knowledge and understanding of the cosmos

[@4me2cclearly]

@Skydancer365 In one of the videos to the right. There is a demonstration of the speed of light. Using high speed cameras to show how the light expands from the bulb. Frame by frame you see the light expanding, at the speed of light. It is a simple experiment to perform with high speed film.

[@EGMAG]

all light particles travel at the same speed only in a vacuum unencumbered by obstacles. Obstacles such as gases and ethe-ric containing particles, in passing phases through space will distort the speed of light. Such obstacles usually cannot be picked up by observing instruments and thus the discrepancies arise.

[@MnM4516]

Well, light doesn't slow down through a medium. It's just that the photons are constantly being absorbed and re-emitted, but they are always moving at C.

[@libalchris]

Neutrinos have been known about for quite some time. It was recently thought after an observation that neutrinos might be able to travel faster than the speed of light. This turned out to be a flaw, and so the speed of light is still the "cosmic speed limit"

[@blurginouliz]

@pane36 1)yes it does.. it has energy and photons wich are particles, thts y it gets sucked into blk holes.. 2)because sonic booms are sound associated, it happens when something travels faster than sound in an atmosfere, it compresses the air vibration crating wat u call a sonic boom... so we could say its like compressed sound, so in the case of light, its particles r too small to push the particles of the air to create a vibration 3)no.

[@eetaq1940]

This is why it is called the theory of relativity. Speed is a relative measurement. It's hard to get your mind around. If you were traveling currently at light speed, relative to yourself your gun would not be moving. You could toss it in the air, and catch it as if you were standing still. Thus, if you shot a bullet out of it, that bullet would travel at normal speed, relative to you. to be continued....

[@PopeBarley]

no. the whole string would not move at once. it would pass as a kinetic wave, it's speed dependent on the kinetic energy input and the elasticity of the string. so the other end of the string would not receive the wave faster the light

[@McGavel1]

Lol, I love the speed limit sign in the beginning.

[@bogie2820]

dmitry, what she is saying is that *IF* there would be an influence from spacetime, then the difference should have been significantly larger than 900ms. The photons traveled for 7,000,000,000 years, so around 245,000,000,000,000,000 times 900ms. This means the .9s difference must have had another cause.

[@31matrix10]

Not one person can have all the answers, thats why sharing and comparing information is key !

[@jqs1943]

Atoms that have a short EMER field correspond to substances that are pliable and elastic like gold, copper, etc.Those that have very long field line correspond to chemical element that bind very tight and their mass is dence.The EMER's field react to what i've name black energies which excite the atom and cause it to radiate its spectral field in the form of light, such as day light. Other forms of lattices expell their fields in colorful expositions that produce the irridiscence of the world

[@dmbernasconi]

They are stating that both the high and low energy particles arrived a the same time, proving that Einsteins theory of space and time is correct, and that other theories stating that space and time are "frothy" are wrong. And no, they are not stating that things are arriving at different times, they are saying they have arrived at the same time. 900ms over 7 billion years negligible, that difference could be within the margin of error for the sensor.

[@stenodictationking9210]

One can travel more than the speed of light, which is the mass because many galaxies are moving away from or at the speed of light or the universe is spreading. There are planets in galaxies too, so this proves that objects can travel at the speed of light even with their mass.

[@awonglol]

@FlyKingRy That is mass and energy relationship. E=(m)(c)(c). That is just for indicate that when how much energy can release when mass deflect occurs on an non-zero mass objects. But not the evidence of "a possible velocity of C * C ."

[@4me2cclearly]

I have seen an experiment demonstrating the speed of light. A bulb was lit in a dark stadium. You could see the glow of the light emit from the bulb and pause it before the light reaches the camera. Now how is it that we can see this glow, before the light even reaches the eye/camera? I thought the eye sees what is projected into the retina. Yet we see the event before the light reaches the eye. Why?

[@screenNameTaken94]

My understanding is the idea is DM causes "lensing" of light, like when it passed through water. It bends it as you state. This has been proven when it pertains to gravity around mass, so I won't argue it. However, presence of DM would make everything look lensed, wouldn't it? So you and I are thinking the same way here.

[@ashleylovesdaddy]

186,000 miles per second is the speed of light in a vacuum. It's a constant only when referring to a vacuum. It has a different speed in other mediums. Hence the rainbow. Or think of the waviness on the bottom of your pool in the daytime. You're still learning.

[@matthe3234]

I have no idea what this guy is explaining but it just sounds so interesting

[@JesusWasAnAsshole]

@TheAlexander356 Yes, of course. Electrons have mass ( 10 ^ -31 kilograms). Therefore, they should be affected by gravity the same as any other amount of mass.

[@zzzIdividedbyzerozzz]

@narutokony The theoretical particles that are suggested to do so are yet to be confirmed to exist.

[@KonKaji]

@boogiebuddy01 I don't know how serious is your question or what kind of prove you're looking for. However one easy way to look at it is, if you're on your computer right now at this time in that place in space(not outer space) then you cannot be in the middle of the ocean or elsewhere at that same time. Your position is based on the time and space you are currently standing. You cannot exist in two places at the same time, therefore time and space go hand to hand.

[@pane36]

i'm going to ask a couple questions that are all linked. 1) does light have mass. if so 2) if light has mass and travels at 186,000mps then why doesn't it create microscopic sonic booms and if it does 3) could this explain multiple dimensions how they say that every single quark of our universe vibrates at a set hps. thanks if someone replies or messages me.

[@fudgedogbannana]

NO, light is not the key in the universe, however, that which propels it at that speed is. Space itself is not stagnant, space doesn't just sit there with everything fling around in it, you heard the scientists say "space is expanding faster than the speed of light. why is that? why is light speed the fastest? isn't it because light is the lightest particle? well space moves faster than light and its everywhere in abundance. isn't everything in space and moving?whats moving it if not space.

[@nomodei]

Go Julie, Go! I am very happy to be part of the crew! A Fermion

[@iamgodf69]

@trZack Neutrinos only go faster than light (photons) in water - where light slows down to 3/4 of its speed in a vacuum -, they do not in fact 'break' the speed of light.

[@screenNameTaken94]

yeah but after traveling for 700 billion years to arrive only 900 ms apart shows they moved at the same speed. That 900 ms difference was likely some other factor. Such as the particle was produced 900 ms after the other.

[@eetaq1940]

However, to a neutral observer, both you and the bullet would be traveling at exactly light speed, because as one goes faster they approach infinity, and subtleties in differences of speed also stretch to infinity. Unfortunately though, your example is hard to explain because its impossible. Nothing can travel at light speed except light, so you would at best be traveling a little under light speed, and your bullet at best be traveling at exactly light speed.

[@arjanodedra6339]

There could be a chance that ther is some things faster then light. Because if the object or thing is moving faster then light then we wont be able to see it as it is moving faster then light so light cant reflect off If u disagree explain please

[@anilsharma09azaz]

Yaa this could be possible but if anything is faster then light so it must have 0 mass according to relativity it should be doing time travelling Possiblity arise we just need more and more scientists and funding

[@sahifaevents8987]

That is assuming the given object is running away from light , what if itself was travelling towards light

[@sahifaevents8987]

@@anilsharma09azaz are you saying light has mass?

[@blackbass4u2c]

Put simply light can have drag the larger the object the more drag that will be applied. Find the source of the drag and energy needs for all will be met. light can slow light ?

[@screenNameTaken94]

especially if DM existed. Although they have observed light being effected around large masses. Very interesting stuff.

[@koihc]

@eliasm307 Let me break it down for you. 900ms difference in 7 billion years, that's 1ms = 10^-3s difference per 7.77~ million years. 10^-9s per 7.77~ years. 4.07697327 x 10^-18s per second. The difference in energy and wavelength between the HIGHEST ENERGY and LOWEST ENERGY photon has to be around or lesser than the amount required to produce a difference of, in distance of light, 4.07697327 x 10^-18s per second. A more probable theory would be that one of the photons was discharged earlier.

[@kindpotato]

@trZack not the discovery but yes neutrinos have been found to go faster than light but they need to confirm it which might take years.

[@Daniel39363]

@OneSummerSky You can travel infinitely close to the speed of light, but you can't actually travel the speed of light. Your headlights would work, and the light coming from them would still appear to go the speed of light due to time and space dilation.

[@rockrollies]

@esraretin But then again they changed the settings and re-ran it 1500 times, so i think it's probably right

[@MarkArandjus]

2:31 I love it when she says that Einstein was right then a picture of him fades in where he's all gangsta with his pipe.

[@MacManLtd]

k wait, so does this close the idea about frame dragging causing light to break the speed limit? The one where a rotating black hole could drag space causing the light traveling trough that space to have relative motion greater than the regular speed limit. Does this mean even if the space was being dragged, this would have no effect on the light, for lack of a better word, the "friction" of space is too low to drag light with it.

[@WaiteDavidMSPhysics]

The second postulate is that the vacuum speed is invariant. Quantum foam having a wavelength dependent refraction index does NOT invalidate relativity. It invalidates the idea that space is vacuum! Damn these public relations physicists are always such a headache.

[@randy95023]

The novice mistake that many people make is that "something out there can travel faster than light". The point is NOT that light is the fastest "thing", it is that light reaches the highest velocity possible for anything with mass. In other words, If something could travel faster than Light, then Light itself would travel faster than it does. It's not just semantics, it's Mathematics!

[@zia83]

How it can tell that the particles with different speed were emitted at the same time at the same origin?

[@Raphy717]

Truly fascinating! There is just so much to learn, astrophysics=awesome.

[@Daniel39363]

@dingovory Look up special relativity. They don't usually teach this stuff in school, you have to go to college before you learn about it. I learned about it on the internet. 2.998x10^8 meters per second is the fastest anything can move in the universe relative to something else.

[@TheTymera]

Photons aren't eternal. They are a form of energy, and thus the energy and momentum photons have were there beforehand but not in the form of a photon.

[@apspacking]

Regarding to the Fact between speed and time, what is the real time that Sun's light reaches the Earth? 8.5 minutes or less? should not the time be shorter when speed is higher.

[@dingovory]

@Daniel39363 Unless I missed it in school, what proof do people have that light is the fastest thing? If you went faster than light, wouldn't your perception of things be the only thing that changes, meaning you experience something before you see it? Isn't it the same concept as a sonic boom, you see the thing before you hear it? I've always wanted a good good physicist to explain this to because I think this whole time travel thing is just perception.

[@Daniel39363]

@wade239 They need to reproduce the data a few more time and check the consistency of their measurement devices before they can call it fact. In theory, if something were to travel faster than the speed of light, it would be going back in time. There is a paradox there though.

[@Nubyrc]

Well he did show very so that gravity effects light (see the eclipse experiments) so what would happen to the photons as they past by multiple gravitational forces through space?

[@Cloudagelo]

its something that connected to electrons and gas as a fabric - the pattern of gas

[@smoothpeople33]

Does it seam right that light shouldn't decay or slow down? What is it that keeps its speed so high over such long distance. Many scientists believe light to have traveled many times faster in the past. If the speed of light is inconsistent then it leaves the door open to limitless theory's.

[@JesusWasAnAsshole]

@blue4596 , in any case, did you see the news this week from Fermilabs ? They think the may have discovered a new particle dubbed the W boson". Cool shit.

[@Cult1022]

i say the speed of light is defined by the gravitational field of the nearest object.

[@Wowfunnyjunior2]

It doesent matter. If something moves even a little bit faster then light it moves backwards in time.

[@425narutofan]

i have a dream. to travel at the speed of light.and im gonna study everything about light.

[@user_z11]

Did you learn everything

[@18CaStRaDoMiS89]

Even traveling at light speed we would still be limited to colonizing our stellar neighborhood. Traveling to objects that are hundreds or thousands of light years away would still be way out of reach.

[@MrJakel111]

soooo.... they are just saying that some light particles move at different speeds in space.... or neutrinos

[@GrifterSixOne]

Doesn't the speed of light (300,000 kps) have something to do with Electromagnetic fields. And its speed is dependent on the observer.

[@Elementalmonk]

Light does not have a speed limit, it disapears making dark spots and re apears somewhere else. Stars are the tipping point the edge of a bounced reflection that has overheated and made gases, solids and liquids = "planets". It is'nt gravity that makes us stable in the rotation it is the planets energy it has its own life light = energy = life.

[@spacefreeman]

Well, anyway she didn't mention alternative explanation. Strictly speaking these Fermi's results didn't refute quantum nature of spacetime. Especially in light of observations performed on other telescopes.

[@matt876mma]

@randy95023 Einstein said, ''nothing can travel faster than the speed of light''. What does that mean? It means he said light was the fastest ''thing''. So there you go mr.smartypants.

[@jewlzorjay]

@dingovory thats interesting, might that explain why you can't see dark matter? perhaps it travels faster then light and cannot be seen.

[@TheZombiesAreComing]

0:22 there's still lots left people still don't know and a lot of what is known is theories.

[@tusharrable]

I have thought of an idea about the universe. So, Can you tell me where can I post my idea?

[@ProttoyEinstein]

Universe is the most mysterious object and once we get all the answers we need, we will be super organisms. But as I think more and more, I am convinced that as we find answers, they lead to more and more questions.

[@hilargiak]

Thaks a lot. Love this.

[@dingovory]

@Daniel39363 Thanks man. That's what I don't like about American schools sometimes, they hold back on some info, probably thinking you're too young for it or whatever. Anyways, your answer is a good start point for research.

[@martini4948]

Thank You Ciao

[@personalsinr]

awesome! love this stuff!

[@MSICSIDUITYE]

@emanmaken what about the expansion of the universe? How does this affect light ,gravity and where does the universe ends ?

[@spacefreeman]

Didn't she tell us that there was 900 ms gap between arrival times of high and low energy photons? And then right after that statement she claims that those photons arrived at the same time. Does anybody have an explanation of her statements?

[@agubaia]

excellent

[@4me2cclearly]

@Skydancer365 My ? was how is it we can see the light, before the light reaches us? Why do we not see a sudden burst of light, once the light reaches the observer, and before that nothing? Or is line of sight instantaneous with the observed event?

[@Jabronite]

Doesn't gravitational lensing come about because of gravity having a strong interference with light? Interesting stuff...good to be somewhat up to date haha

[@tlatitude8586]

Could it be that the radiation is traveling at the same speed, but that the higher energy gamma just has farther to travel, because of the wavelength and frequency?

[@franciswywy]

actually he was wrong couple times, for example when he said the universe is shrinking since we all know it is expanding, and he was also wrong when he created the atomic bomb.....

[@baddalbatross42]

Thanks for the reply...and the heads up on the name. How could we forget ? ~ lol ~ It would seem that when watching...and listening to her describe and theorize about things that boggle my mind..i.e. Quantum Mechanics or the Space /Time Continuum...ect. I find she makes it easy to let the mind fade in and out between Astrophysics and Biology at times...wonder what's up with that ? (ha ha) Two of the fundamentals of nature...she a great teacher. ;P Later

[@KHShox]

No, that was a malfunction in the measurement systems.

[@OpionatedOldMan]

Einstein isn't absolutely correct, BECAUSE in reference to the speed of light, light has various waveLenths. Therefore, it is a VARIABLE, rather than a CONSTANT...

[@spilloholiker]

Yaaay. GRB's I just made a scientific poster about Gamma-ray bursts

[@thepcguy01]

science just got more exciting!

[@Wasakracker79]

When the universe got born,it expanded the first microseconds,faster then the speed of light.

[@SCORP1ONF1RE]

really??

[@supreemsharma4737]

every object in this universe is acclerating when it start from rest to motion but why light is not acclerating that condition? there is no any object that can possess a constant speed suddenly after rest it need to be acclerate to be in a constant speed . but why light is not acclerating ? plzzz guys give me some idea reguarding this ......

[@SarathyKannanG]

Its then said that there was some experimental errors in determining the speed of neutrino's.

[@1RadicalOne]

Foamy enough to interfere with light? Spacetime is irregular, but not THAT bumpy.

[@KonKaji]

@smoothpeople33 Indeed, I believe that can lead to many disturbing thoughts. If light really is inconsistent, just think, in far far future if light were to slow down how it would affect us physically. The light emitted on objects and reflected back to our eyes would have greater delayed; since we are already experiencing about one billionth of a second delay. Good question, what keeps it at high speed. I don't know and decaying doesn't seem right because space is isotropic, as we know so far.

[@808yougamer]

still didn't explain why other telescopes observed different gamma rays arriving on earth at different times

[@ahsanullahleghari6559]

sir my first question is that why a long time before the people were live 1000 years but now we live only 80 to90 year.and 2nd is why earth have spin motion.sir i have something about these question in my views may be it wrong or right.where i live nobody don`t bealive NASA i want to contact you if you want.

[@NsaneNtheNbrane]

Even if the fabric of spacetime is bumpy, it wouldn't actually slow down a photon. What would happen is that the photon would just bump around on the fabric like a pinball in a pinball machine, slightly changing direction, but never actually changing speed. That's also what happens with glass. Ever since Einstein came up with relativity, people have been trying to prove him wrong. And they've all FAILED.