I`ve read that Isaac Asimov came up with that term ("celeritas") as a `probable` reason for using the symbol `c`. The fact of the matter is, the reason is unknown.
can't i get an incoming object to accelerate beyond the speed of light ,so that it will pass me before i see it? would i need to transform all its mass to energy to achieve that?
@partonace The speed of light in vacuum is an experimentally measured number. As such, when expressed in scientific notation, has as many decimal places as the finite precision of the measuring apparatus will allow.
Idealistically, given a measuring apparatus with INFINITE precision, it is reasonably assumed that this experimentally measured number converges to some real number that we denote by `c`.
@LeconsdAnalyse can it be proven that the experimentally determined number (what effect does the measurement itself have on the situation?) really converges to "some real" number which only appears as a fiction? it doesn' t make it more convinving to add some metastatements like "reasonably" - quite the contrary is true: that the addition of such metastatements rather shows: there's something fishy.
@partonace What are you talking about (?). As with all other experimentally measured quantities there is experimental `uncertainty`. For example, c = 299,792.4562±0.0011.
@LeconsdAnalyse Tell me something new. It ain't an experimental uncertainty. It's a certain accuracy which depends on how lazy and/or limited the experimentator is. Then she or he begins to babble "it's not me it's nature itself that sets up those limits of accuracy". Blabla. An actual experiment has no uncertainty. It is completely accurate (= 0 uncertainty = highest probability of being 100% accurate) if the experimentator takes her or his time to analyze the whole setting.
@LeconsdAnalyse only the limited mind that realizes that it also can profit from a way lower degree of analyzation of the whole setting will begin to babble of the uncertainty of an experiment. if there is an uncertainty further analyzation has to be done. this is not engineering but science and research.
Just a few academic aristocrats pontificating to the masses and calling it education. There is no science involved in this video at all. If they believe that the speed of light is constant in all frames of reference they need to at least mention some observational or experimental evidence.
What will happen if i'm at the back of the train that is traveling at the speed of light, then i run to the front of the train. Will I exceed the speed of light?
@MrThatmeanguy1995 Unfortunately you would not be able to exceed the speed of light. The reason is because time would be almost at a standstill relative to you on the train. Theoretically if you exceeded the speed of light time would stop all together.
@skaught911 To an outside observer time would seem to stop, for you it would not, time would seem the same only the laws of the natural world would begin to break down and get confusing... They better explain the time thing in another video I think, using 2 trains and the reaction speeds of the people.
@baadshepherd I'll have to definitely watch their other videos haha, but one thing that I couldn't get over was wouldn't time eventually get slowed to the point where conscious thought could no longer be processed? I could be miles off from understanding this correctly.
@skaught911 The person travelling experiences time as normal, it just looks to the observer of his movement that he is moving slowly or not at all. I can't really remember how they explain it, but they do have a video on it, and the fun of watching these videos is learning new things anyway, so I say just keep watching random ones and watch the related videos.
You cannot measure the precise speed of light by bouncing a radio wave off the Moon or a planet, because in order to do that, you would first have to measure an exact baseline. Yet the Earth and the target are constantly moving: spinning in space, orbiting, etc. So the baseline is continually changing. The only place the speed of light has ever been measured is at the surface of planet Earth. Its constancy is theoretical rather than empirical.
The whole "faster than light" particle is nothing new, it was predicted around 50 years ago. Search up "tachyon", it seems these neutrinos may be part of that group.
@mathijab it's a matter of semantics actually. tachyons are a theoretical conjecture, and imaginary particle that travels faster than the speed of light. Neutrinos are simply real subatomic particles that have that same property. you can think of them as the same thing only one is theoretical and one is not. tachyons i suspect were simply made up for the purposes of pondering what would happen if there was a particle faster than light. feel free to correct me though if im spouting bullshit. :3
@LeconsdAnalyse Yes, some people are saying that the CERN neutrinos must have been tachyons, since they appear to have traveled faster than light. Either there were systematic errors in the experiments (which I personally doubt), or the speed of light is not constant. Neutrinos definitely travel at the speed of light (even if it's a variable) based on neutrino detections from Supernova 1987a.
`Tachyons` are fictitious objects created just for mathematical reasons, like (say) the extra compact dimensions (beyond the four used in relativity) of `String theory`. They have never been experimentally proven to exist.
At the scale involved in GR light is a continuous beam of photons with both energy (E) and linear 3-momentum (p). When there is a gravitational potential present the light loses energy, and momemtum (since, E=||p||c)!
Suppose that initially the light is (before passing through the horizon) monochromatic (no gravitational potential; and fixed λ,v where λv=c). So then initially the light possesses a well defined energy given by (Planck): E=hv=||p||c.
After entering the horizon and approaching the singularity E=hv→0+ through the spectrum of light (a multichromatic change). But the speed of the light (in vacuum) stays fixed at `c`! Viz., v decreases and λ increases s.t., λv=c.
@LeconsdAnalyse Thanks ! The speed of light is constant only in a vacuum. Light travels faster through warm air than it does cold ? Black holes kill lights energy ? So maybe the big bang was a super detonation/inflation with the shock wave travelling at the speed of light and that's why the universe is the same temperature everywhere we look ? Crazy theory number 4583 :-/
I am interested that Maxwell in his key work on this used V for the speed of light and so did Einstein in the original German papers of 1905 - I wonder when c came to be the recognised designation which it certainly is now.
Maxwell when he developed his equations for electromagnetism found that in his equations he could derive a velocity for the waves which was made up of two other known constants mu and epsilon - and that this velocity was invariant - it was this that Einstein used to say the speed of light was a constant or one of the reasons and this velocity coming from non-velocity components i.e. 1/SQRT(mu*epsilon) was remarkable.
@johncrwarner I was not aware of this, so thank you :)
But what I was thinking of, is when people say that the speed of light is C, isn't it just C by definition? Because distance is just the length of part of the speed of light, wouldn't that make it C simply because we say so?
When people talk about the speed of light being a constant they mean that the speed of light in a vacuum is a constant - relative to anyone in the universe - if I am moving relative to you at half the speed of light - I still measure light to be travelling at the same speed. That is the weird thing - that is why we need to refine our ideas of mass, time and distance at the beginning of the 20th century because of that remarkable fact.
It would appear normal to you, as the traveller. To a stationary observer, the light would move forward slowly in relation to the vehicle....this is reconciled by time slowing down for the traveller.
@thealien19 I asked my physics teacher that, and he said "I dunno, cos some crazy and wierd shit happens when you're travelling at the speed of light"
@thealien19 the lights from the car would keep travelling at the speed of light, light is a constant. did u go to school? u actuley got thumbs up for that aswell. what is this world coming to?
@thealien19 Nothing, your own speed has no impact upon the speed of light as projected from you. IE, you would see no light projected before you. Like they said in the video.
if light is 299792458 meters long - is matter then just wound up light going in circles (or maybe spirals like galaxies)? per second? do i measure a length per time? well - it for sure is sure that for example a rod or any other "line" will "decay" - but di i measure the length of a rod per time? why not? why are some things put in such a relation and some aren't. And what about the details of the rod where it all starts to "wiggle"?
@WMfin lightspeed, although an object which has a mass greater than zero would need an infinite amount of energy to reach c. If you flew at the same speed as the laser pointer, you'd see the beam fly off at c; if you were sitting here on Earth and watching the pointer fly past you'd see it and the laser beam it generates flying at the same speed.
@WMfin No, as I understand it, you can't accelerate light based on your speed. So, in that case, if you were travelling at 100% the speed of light as you turned on the laser pointer, you would see no light.
As they said in the video, the speed of light (c) is a constant regardless of your speed.
Assuming all of this is taking place in a vacuum with no hindrance to light. That's how I understand it.
@Tridecalogism So, If I go 99% the speed of light and turn on the laser pointer, light from it would go 1% the speed of light? Thanks from your comments guys!
However, let's say that in this argument, light travels at 100 meters per second.
If you travel at 99% the speed of light, you travel at 99 meters per second.
So, if you turn a torch, or laser on, in the direction you are travelling (exactly), the light emitted from the torch or laser would accelerate away from YOU (relative) at 1 meter per second.
@Tridecalogism light doesn't travel. it's as if you say that the letters on an led sign travel - while the led's are just "flashing" (are they doing this of free will - i know how you'll answer because you don't have free will - neither do i - but i am ok with it since i give a fuck about discussions about free will and determinism) on and off.
If you travel ALMOST at the speed of light, YOU will see the laser go away at lightspeed infront of you (300,000,000 meters per second). But this ONE SECOND for YOU could be like a THOUSAND YEARS on EARTH, depending on how fast you are moving. We will see the light in front of your spaceship going at 300,000,000 meters per "OUR" second, and you will see it moving 300,000,000 meters per "YOUR" second. It is the time that is different for us.
i have a question, people say black holes gravity is so stong that it can hold time or like shocks comment above above but how could this happen if time is a measerment made by humans, please answer
@ispravljat You shouldn't look at humans as individuals in this case as the discourse is about why not all molecules can be sensed. The other senses are also not related to this discussion.
@qwerty657ful All electromagnetic waves are considered light. What we can see is visible light. As long as the medium is optically denser (there is a difference between dense and optically dense), the waves will slow down.
@Aviatorsmith Do they slow down by the same ammount for example i pass light through a glass block and it slows down to a differnt speed, if i where to then pass X-rays through the same block of glass would it slow down by the same aamount?
@qwerty657ful No, they don't; you can see it when a prism breaks up white light into its component colours and forms a rainbow; that happens because each colour (frequency) is slowed down by a different amount, so they are bent by different angles at the interface between air and prism and thus separate.
@ispravljat Yes, your senses do not differ from each other in the way they transmit information to the brain. But they do differ in the types of information they gather. The way your brain processes those signals are not the same.
You can't smell all of the molecules because the human olfactory organ is crude. As I have said, only molecules which can fit into the receptors can be "sensed". We have evolved such that what we can smell are the smells that are most relevant to us.
@ispravljat The sense of smell doesn't differ from other senses. They all take information supplied to the sensory organ and turns it into electrical signals that get transmitted to the brain.
Smell molecules are molecules just like any other. The nose works by taking these molecules emitted by a source and turning it into electrical signals. Those molecules "fit" into certain receptors in the nose. Different smell molecules will fit into different receptors to produce different signals.
@ispravljat The speed of smell is dependent on the amount of kinetic energy the smell molecules or atoms possess, most likely in the form of heat energy. The speed of heat is dependent on how conductive a material is. In the case of He4 at 1.8k, it is around 20m/s. For other materials it is considerably slower, several hundred times in fact.
Whoa hold on! What was that last bit? A calculator with the constants on it? I just emailed Sigma Aldrich to try and get them to make one with the periodic table on it, along with things like nomograph functions for calculating new vapour pressures etc. The guy didn't get my point though. I meant a physical pocket calculator, not the online one.
The C is derived from "celeritas", -atis: (Latin) meaning speed; quickness; and in his 1905 equation regarding the theory of special relativity "c" represents the velocity of light, about 186,000 miles per second. And this speed is the same for any observer in any inertial frame, no matter how one is moving relative to the source of the light, and it is impossible to accelerate an object from below the speed of light up to the speed of light.
@xenophonon123 what about non- and anti-inertial frames? how can it be called relativity when the speed of light is being sold as an absolute value (which is questionable since speed is a ratio and therefore relative by heart). can you tell me one way where i can measure the speed of light on my own and with household materials? you ...
@xenophonon123 ...don't tell the context of the speed of light. it's an open question if the speed of light can be slower than the speed of "matter" (you're typing about moving an object - but what about the object itself if you go to "deeper" and "deeper" scales) and the speed of matter (not an object being moved but the "details of an object moving to make up that object) being faster than light.
@xenophonon123 i expected one of them, when they said "i'm not sure", to say it proabably means someting in Latin which is what i was thinking. Thanks for clarifying
@Shockszzbyyous Great question. Theory suggests, that time is basically a direction. distance=rate*time right? So basically (you need to open your mind for this one) time spreads at the speed of light. When getting closer to this speed, you *catch up* with time so to speak. That's why reaching the speed of light is impossible. If you reach it, your observing time is zero and thus you can not be moving at all. So time being a dimension also makes it a barrier for other dimensions to cross.
Hello. It is because of the metric, ds²=-c²dt² + dx² + dy² + dz² and the definition of `proper time` (τ), dτ²:= -c⁻²ds². The metric may be rewritten as dτ²= (1-v²/c²)dt², with v²≡(dx² + dy² + dz²)/dt². So that, γ(τ₂-τ₁)=t₂-t₁ which is the equation for `time dilation` (γ := 1/√(1- v²/c²)). For example, if v=c√3/2 then γ=2 and, 2(τ₂-τ₁)=t₂-t₁. That is, time ticks one-half times more slowly for the inertial frame in relative motion.
@Shockszzbyyous why is a hard question to answer but it happens because you HAVE to be able to shine a flashlight forward while moving 99.9% the speed of light and have it appear to you that the light is leaving the flashlight at the speed of light. if time did not slow, relativity would fail.
@Shockszzbyyous Because, since light is the same in every perspective (frame of reference) something has to be changing and that is time. e.g. You're in a train going at half of light and you turn on headlights, you see that beam go at light speed. But if you are outside you will also see the beam of light going at light speed, not speed of light + half of speed of light.
@Shockszzbyyous because if you were on a train traveling at 99.999...% of the speed of light, if somebody got up on that train the combined speed would be greater than the speed of light. therefore, time slows down, relative to the speed that an object is traveling. 0mph is the absolute slowest that time can go (although it is impossible to tell if you are at 0) and at the speed of light, time stops to stop anything exceeding it. lol its so confusing :)
@Shockszzbyyous If you are the one travelling near the speed of light, and you are going in a straight line (ie not changing speed or direction) time appears perfectly normal to you. You won't notice any slowing down. Allow me to recommend the following YouTube vid: Search for "Einstein's Relativity and the Quantum Revolution Modern Physics part 1". He explains it beautifully for non-physicists.
@Shockszzbyyous The simplest explanation is that c is your cosmic speed through spacetime. You are travelling through spacetime at c, and always at c, it's yours to spread across the four dimensions. If you use alot of speed to move through the 3 spacial dimensions, then you have less speed left over to move through the time dimension.
@Shockszzbyyous Time is layed out on a fabrik we call Space Time Fabrik. This fabrik gets bent by gravity.
E=MC^2. So Energy = Mass^2. So when you create the energy from movment, it also adds to the mass. and at the same time, the actual area the mass is filling shrinks. Therefore, because more mass is in the same place, the gravity around that object will be stronger. As you aproch the speed of light, this mass to space ratio goes up to nearly infinite (Hitting the speed of light would mean
@olivebates Theres an infinite amount of mass in one place. Witch would be physically impossible as it would collaps the whole univers (probably)). As your mass goes up to near infinite, the gravity will be so strong, it bends the Space Time Fabrik nearly infinitly, meaning time it self will slow down.
@olivebates This is the same argument that scientists used to say why we would never exceed the speed of sound. In the sound case, the fabric we were compressing was the air in front of the airplane. As it turned out the problem was solved by engineers. The speed of light limit will turn out to be the same case of science versus engineering. It's up to the engineers to solve the problem.
c comes from Latin celeritas (meaning "swiftness"). Look up speed of light in wikipedia for the history, including what symbols were used for the speed of light before c was used.
b/c if it is instant, you could create a gravitational oscillator, say create a mass then destroy it and create it again, if you could make a machine to do this and make a receiver, you would have instantaneous communication.
heres a legitimate question no one has ever been able to give me a good answer. What is the speed of gravity? not the acceleration, like suppose an object with mass just appeared, would the gravity be instantly perceivable or would it take time like light for the effect to be measured?
Just curious if you could travel that fast, would you be able to look out the window and see if the "light" was keeping up? or would you be unable to see it because even though it was traveling along side of you the delay was too great?
Furthermore, the speed of light will never be proved incorrect, zzzIdivededbyzerozzz. The metre is defined as how long it takes light to travel a certain distance. So if anything, the metre will change.
This video is ambiguous in some ways. First light never slows down. It "appears" to slow down through some materials. It is not an absorption/reemission from atoms either, as many people think. It is the vibrations of the electrons of the atoms that create more EM waves that interact with the incoming EM. This interference causes an extremely complex phenomenon. Richard Feyman and the study in QED has the answers.
Light does not slow down, ever. Light does need to interact with atoms that it comes within a certain proximity of, and retransmission takes 10^-15 seconds to complete. So, roughly speaking, the denser a space is with atoms the slower a beam of light passes through it, but if that beam had a speedometer it would always say c m/s.
3000 km per second. Trip to the moon and back, about four minutes. I hope they find a way to slow down light in such a way it doesn't speed up again when it leaves the material slowing it down.
Okay, the speed of light is a universal speed limit. So, how does this speed limit exist at the same time as entanglement? Entanglement is a bizarre phenomenon where two objects communicate their state with each other, instantaneously, no matter how far apart they may be, seemingly breaking the limit of "c." How is this possible? How does it work?
I am always stunned how fast michael can talk....when i started watching the videos i couldn't follow him...but now i think i like him (well..the way he explains things...not him himself because i don't know him....)
they used the symbol c for celerity of light :)
Frankotronify 3 days ago
@Frankotronify Hi.
I`ve read that Isaac Asimov came up with that term ("celeritas") as a `probable` reason for using the symbol `c`. The fact of the matter is, the reason is unknown.
LeconsdAnalyse 1 day ago
can't i get an incoming object to accelerate beyond the speed of light ,so that it will pass me before i see it? would i need to transform all its mass to energy to achieve that?
frizstyler 6 days ago
@frizstyler 1. "so that it will pass me before i see it".
This will also occur at speeds v≤c due to human reaction time.
2. "get an incoming object to accelerate beyond the speed of light".
This is a situation that SR does not predict.
LeconsdAnalyse 4 days ago
@LeconsdAnalyse i wasn't talking literally about me seeing it. lol.. i would die because it would pass through me anyway
frizstyler 4 days ago
This has been flagged as spam show
how much energy would be needed to slow the speed of light down? and how would that be done exactly?
partonace 1 week ago
how much energy would be needed to really slow light down?
partonace 1 week ago
@partonace Light in vacuum will always travel with speed `c`. It cannot be slowed down.
You can change its energy & frequency in accord with E=hv (or, its energy & momentum in accord with E=pc).
LeconsdAnalyse 4 days ago
@LeconsdAnalyse ....but it never does travel with the idealistic c.
partonace 4 days ago
@partonace The speed of light in vacuum is an experimentally measured number. As such, when expressed in scientific notation, has as many decimal places as the finite precision of the measuring apparatus will allow.
Idealistically, given a measuring apparatus with INFINITE precision, it is reasonably assumed that this experimentally measured number converges to some real number that we denote by `c`.
LeconsdAnalyse 4 days ago
@LeconsdAnalyse can it be proven that the experimentally determined number (what effect does the measurement itself have on the situation?) really converges to "some real" number which only appears as a fiction? it doesn' t make it more convinving to add some metastatements like "reasonably" - quite the contrary is true: that the addition of such metastatements rather shows: there's something fishy.
partonace 3 days ago
@partonace What are you talking about (?). As with all other experimentally measured quantities there is experimental `uncertainty`. For example, c = 299,792.4562±0.0011.
LeconsdAnalyse 3 days ago
@LeconsdAnalyse Tell me something new. It ain't an experimental uncertainty. It's a certain accuracy which depends on how lazy and/or limited the experimentator is. Then she or he begins to babble "it's not me it's nature itself that sets up those limits of accuracy". Blabla. An actual experiment has no uncertainty. It is completely accurate (= 0 uncertainty = highest probability of being 100% accurate) if the experimentator takes her or his time to analyze the whole setting.
partonace 2 days ago
@LeconsdAnalyse only the limited mind that realizes that it also can profit from a way lower degree of analyzation of the whole setting will begin to babble of the uncertainty of an experiment. if there is an uncertainty further analyzation has to be done. this is not engineering but science and research.
partonace 2 days ago
c stands for celeritas by the way. Meaning speed in Latin.
XAttaHabibX 1 week ago
Would it be correct to say that for a photon in a vacuum, the universe is a dot and time stands still?
udoloh 3 weeks ago
12222222 view..win
elflordbob1 3 weeks ago
c is celeritas (from latin)
gnomeosaurus 3 weeks ago
@ 1:10 he answered his question. its c because its constant...?
Shift4chizzle 3 weeks ago
I AM LIVING AT c! no, just, no. that does not work...ugh.
I AM LIVING AT THE SPEED OF LIGHT!!! oh yes.
TROLL!
Iamyoubestfreind 3 weeks ago
Comment removed
LeconsdAnalyse 1 month ago
Zeno's riddle, hm.
motionapplied 1 month ago
the symbol c comes from the latin word celeritas which means "speed".
dickenzon 1 month ago
Comment removed
LeconsdAnalyse 2 months ago
So what happens now that it has been broken?
MNDNM 2 months ago
@MNDNM you blake you cry
I blake I buy
knytebyte1 1 month ago
Just a few academic aristocrats pontificating to the masses and calling it education. There is no science involved in this video at all. If they believe that the speed of light is constant in all frames of reference they need to at least mention some observational or experimental evidence.
ronc8141 2 months ago
What will happen if i'm at the back of the train that is traveling at the speed of light, then i run to the front of the train. Will I exceed the speed of light?
MrThatmeanguy1995 2 months ago
@MrThatmeanguy1995 Unfortunately you would not be able to exceed the speed of light. The reason is because time would be almost at a standstill relative to you on the train. Theoretically if you exceeded the speed of light time would stop all together.
skaught911 2 months ago
@skaught911 To an outside observer time would seem to stop, for you it would not, time would seem the same only the laws of the natural world would begin to break down and get confusing... They better explain the time thing in another video I think, using 2 trains and the reaction speeds of the people.
baadshepherd 1 month ago
@baadshepherd I'll have to definitely watch their other videos haha, but one thing that I couldn't get over was wouldn't time eventually get slowed to the point where conscious thought could no longer be processed? I could be miles off from understanding this correctly.
skaught911 1 month ago
@skaught911 The person travelling experiences time as normal, it just looks to the observer of his movement that he is moving slowly or not at all. I can't really remember how they explain it, but they do have a video on it, and the fun of watching these videos is learning new things anyway, so I say just keep watching random ones and watch the related videos.
baadshepherd 4 weeks ago
Pause at 3:00 and cover his hair
RandomFilmStudio 3 months ago 8
@RandomFilmStudio Haha, I don't get it
pythor2 2 weeks ago
Comment removed
LeconsdAnalyse 2 weeks ago
You cannot measure the precise speed of light by bouncing a radio wave off the Moon or a planet, because in order to do that, you would first have to measure an exact baseline. Yet the Earth and the target are constantly moving: spinning in space, orbiting, etc. So the baseline is continually changing. The only place the speed of light has ever been measured is at the surface of planet Earth. Its constancy is theoretical rather than empirical.
SuperMagnetizer 3 months ago
The whole "faster than light" particle is nothing new, it was predicted around 50 years ago. Search up "tachyon", it seems these neutrinos may be part of that group.
So stop thinking it's a "just new" concept -__-
DarkGamanoid 4 months ago
@DarkGamanoid they found neutrinos, not tachyons
mathijab 3 months ago
@mathijab it's a matter of semantics actually. tachyons are a theoretical conjecture, and imaginary particle that travels faster than the speed of light. Neutrinos are simply real subatomic particles that have that same property. you can think of them as the same thing only one is theoretical and one is not. tachyons i suspect were simply made up for the purposes of pondering what would happen if there was a particle faster than light. feel free to correct me though if im spouting bullshit. :3
ryankO0sh 3 months ago
Comment removed
LeconsdAnalyse 3 months ago
@LeconsdAnalyse Yes, some people are saying that the CERN neutrinos must have been tachyons, since they appear to have traveled faster than light. Either there were systematic errors in the experiments (which I personally doubt), or the speed of light is not constant. Neutrinos definitely travel at the speed of light (even if it's a variable) based on neutrino detections from Supernova 1987a.
SuperMagnetizer 3 months ago
@SuperMagnetizer Hey super :)
LeconsdAnalyse 3 months ago 8
@LeconsdAnalyse Hej Leconsd :)
SuperMagnetizer 3 months ago
they sat on the Neutrino data for two years to make 100% certain they reading were correct.
justincgs 4 months ago
@justincgs and people are still skeptical
johnball235 3 months ago
and now we have something that is faster than the speed of light... probably.
It's called Neutrino, a sub atomic particle. Waiting for confirmation...
you can google "Neutrino" for the latest news
Th0usandMaster 4 months ago
@Th0usandMaster probably is ABSOLUTE with six sigma confirmation !!! Many a physicist isn't sleeping tonight! LOL
justincgs 4 months ago
is "c" linked to the expansion of the universe?
VederchiHarry 4 months ago
@VederchiHarry
YES, if by `linked` you imply if `c` appears in the THEORY of the expanding universe.
LeconsdAnalyse 4 months ago
@LeconsdAnalyse By "linked", I mean : " as the Universe expands, "c" increases just as well".
The result would be that the traveltime of light between star A and star B is always the same (when the stars are only influenced by the expansion).
VederchiHarry 4 months ago
@VederchiHarry
Nope, c is the same in vacuum everywhere relative to "here".
But, time changes with travel speed and gravitational influence.
And, the further away stuff is relative to "here" the faster it moves away from "here".
melis256 4 months ago
@melis256
I find it amazing how few people know
that the speed of light in a vacume can change
and was changed in 2004 by a beautifull experiment.
;
just a heads up.
bulkburn 4 months ago
i heard of somthing that travels faster then the speed of light, does it travel in time?
jeepvsix 4 months ago
@jeepvsix tachyons is faster then the speed of light so does it travel in time?
jeepvsix 4 months ago
@jeepvsix Hello.
`Tachyons` are fictitious objects created just for mathematical reasons, like (say) the extra compact dimensions (beyond the four used in relativity) of `String theory`. They have never been experimentally proven to exist.
LeconsdAnalyse 4 months ago
@LeconsdAnalyse thnx for the repley, i really tought it was proven but i must misunderstood that when i heard of it.
jeepvsix 4 months ago
Comment removed
LeconsdAnalyse 4 months ago
Doesn't c stand for "celerity" ?
synsei1 4 months ago
I heard there's a distant Galaxy moving around 3 times the speed of light, how the?!?
mickenoss 5 months ago
This has been flagged as spam show
No matter how tempted you get, NEVER type the words 'thirteen horror' into Bing or Google...
... and if you do, DO NOT attempt the dare it will try and persuade you to try.
ThirteenVolumeOne 5 months ago
If light can't escape black holes then how can light be a constant speed ?
twistedbass15 5 months ago
@twistedbass15 Excellent question!
1/2
At the scale involved in GR light is a continuous beam of photons with both energy (E) and linear 3-momentum (p). When there is a gravitational potential present the light loses energy, and momemtum (since, E=||p||c)!
Suppose that initially the light is (before passing through the horizon) monochromatic (no gravitational potential; and fixed λ,v where λv=c). So then initially the light possesses a well defined energy given by (Planck): E=hv=||p||c.
LeconsdAnalyse 4 months ago
@twistedbass15
2/2
After entering the horizon and approaching the singularity E=hv→0+ through the spectrum of light (a multichromatic change). But the speed of the light (in vacuum) stays fixed at `c`! Viz., v decreases and λ increases s.t., λv=c.
LeconsdAnalyse 4 months ago
@LeconsdAnalyse Thanks ! The speed of light is constant only in a vacuum. Light travels faster through warm air than it does cold ? Black holes kill lights energy ? So maybe the big bang was a super detonation/inflation with the shock wave travelling at the speed of light and that's why the universe is the same temperature everywhere we look ? Crazy theory number 4583 :-/
twistedbass15 4 months ago
I'm really surprised none of them knew the word, "celerity."
mdiem 5 months ago
why the fuck did i go on this!?
Xcardy13 5 months ago
I am interested that Maxwell in his key work on this used V for the speed of light and so did Einstein in the original German papers of 1905 - I wonder when c came to be the recognised designation which it certainly is now.
johncrwarner 5 months ago
Here's what I'm curious about. Isn't the speed of light what it is by definition?
kfk4life 5 months ago
@kfk4life
Maxwell when he developed his equations for electromagnetism found that in his equations he could derive a velocity for the waves which was made up of two other known constants mu and epsilon - and that this velocity was invariant - it was this that Einstein used to say the speed of light was a constant or one of the reasons and this velocity coming from non-velocity components i.e. 1/SQRT(mu*epsilon) was remarkable.
johncrwarner 5 months ago
@johncrwarner I was not aware of this, so thank you :)
But what I was thinking of, is when people say that the speed of light is C, isn't it just C by definition? Because distance is just the length of part of the speed of light, wouldn't that make it C simply because we say so?
kfk4life 5 months ago
@kfk4life
When people talk about the speed of light being a constant they mean that the speed of light in a vacuum is a constant - relative to anyone in the universe - if I am moving relative to you at half the speed of light - I still measure light to be travelling at the same speed. That is the weird thing - that is why we need to refine our ideas of mass, time and distance at the beginning of the 20th century because of that remarkable fact.
johncrwarner 5 months ago
@sixtysymbols what would happen, if you turn on the frontlights of a vehicle travelling at the speed of light?
thealien19 5 months ago 10
@thealien19
It would appear normal to you, as the traveller. To a stationary observer, the light would move forward slowly in relation to the vehicle....this is reconciled by time slowing down for the traveller.
kshackleton 5 months ago
@thealien19 The light will still move at C
kfk4life 5 months ago
@thealien19 You could never get a car to reach the speed of light, the force would change its state.
Mattc23q 5 months ago
@thealien19 I asked my physics teacher that, and he said "I dunno, cos some crazy and wierd shit happens when you're travelling at the speed of light"
supermanondrugs1 5 months ago
@thealien19 NOTHING :)
zeus018 4 months ago
@thealien19 the lights from the car would keep travelling at the speed of light, light is a constant. did u go to school? u actuley got thumbs up for that aswell. what is this world coming to?
british123able 3 months ago
@thealien19 as of Einstein's relativitation theory, nothing with mass can travel with the speed of light...
simben4 2 months ago
@thealien19 Nothing, your own speed has no impact upon the speed of light as projected from you. IE, you would see no light projected before you. Like they said in the video.
DeathbyDusk 2 months ago
Comment removed
LeconsdAnalyse 2 months ago
@thealien19 I'm fairly sure time stops
FaShizzleMaNizzle1 1 month ago
Why should time only be one-dimensional and un-orthodox (got that little wordplay here?) /unconventional?
vertexgo 6 months ago
if light is 299792458 meters long - is matter then just wound up light going in circles (or maybe spirals like galaxies)? per second? do i measure a length per time? well - it for sure is sure that for example a rod or any other "line" will "decay" - but di i measure the length of a rod per time? why not? why are some things put in such a relation and some aren't. And what about the details of the rod where it all starts to "wiggle"?
vertexgo 6 months ago
What would happen you could add mass to light?
12co3dy21 6 months ago
So if you have laserpointer that goes speed of light and shoots light, that shooted light goes c or c * 2?
WMfin 6 months ago
@WMfin What do you mean?
Tridecalogism 6 months ago
@Tridecalogism If laserpointer travels speed of light and shoots laser, how fast that laser go. Lightspeed or lightspeed x 2?
WMfin 6 months ago
@WMfin lightspeed, although an object which has a mass greater than zero would need an infinite amount of energy to reach c. If you flew at the same speed as the laser pointer, you'd see the beam fly off at c; if you were sitting here on Earth and watching the pointer fly past you'd see it and the laser beam it generates flying at the same speed.
wtrmute 6 months ago
@WMfin No, as I understand it, you can't accelerate light based on your speed. So, in that case, if you were travelling at 100% the speed of light as you turned on the laser pointer, you would see no light.
As they said in the video, the speed of light (c) is a constant regardless of your speed.
Assuming all of this is taking place in a vacuum with no hindrance to light. That's how I understand it.
Tridecalogism 6 months ago
@Tridecalogism Correct me if I'm wrong... I'm not a physicist etc.
Tridecalogism 6 months ago
I think he said that you can't get light to travel faster, but you can get it to slow down.
Tridecalogism 6 months ago
@Tridecalogism So, If I go 99% the speed of light and turn on the laser pointer, light from it would go 1% the speed of light? Thanks from your comments guys!
WMfin 6 months ago
@WMfin Relative to you, yes. I guess so.
However, let's say that in this argument, light travels at 100 meters per second.
If you travel at 99% the speed of light, you travel at 99 meters per second.
So, if you turn a torch, or laser on, in the direction you are travelling (exactly), the light emitted from the torch or laser would accelerate away from YOU (relative) at 1 meter per second.
Tridecalogism 6 months ago
@Tridecalogism Note that I say it travels away from YOU at one meter per second, because it's relative to you.
Tridecalogism 6 months ago
@Tridecalogism Fascinating! Thank you! :)
WMfin 6 months ago
@WMfin ...oh, i "thought" you typed "fasci-st". But what's confusing/interweaving you?
vertexgo 6 months ago
@vertexgo It was that one question I asked and I had interesting answers :)
WMfin 6 months ago
@Tridecalogism light doesn't travel. it's as if you say that the letters on an led sign travel - while the led's are just "flashing" (are they doing this of free will - i know how you'll answer because you don't have free will - neither do i - but i am ok with it since i give a fuck about discussions about free will and determinism) on and off.
vertexgo 6 months ago
@vertexgo I'm sorry, but I happen to believe that, while the actual diode doesn't 'travel' the light it emits does.
Tridecalogism 6 months ago
Just curious, are you trolling?
Tridecalogism 6 months ago
@WMfin
I think what Tridecalogism want to say is:
If you travel ALMOST at the speed of light, YOU will see the laser go away at lightspeed infront of you (300,000,000 meters per second). But this ONE SECOND for YOU could be like a THOUSAND YEARS on EARTH, depending on how fast you are moving. We will see the light in front of your spaceship going at 300,000,000 meters per "OUR" second, and you will see it moving 300,000,000 meters per "YOUR" second. It is the time that is different for us.
xxxx85 6 months ago
@xxxx85 "time is relative to the observer"? :)
WMfin 6 months ago
i have a question, people say black holes gravity is so stong that it can hold time or like shocks comment above above but how could this happen if time is a measerment made by humans, please answer
akbeast49 6 months ago
The "c" comes from the latin word "celeritas", which means quickness.
wtrmute 6 months ago
@ispravljat You shouldn't look at humans as individuals in this case as the discourse is about why not all molecules can be sensed. The other senses are also not related to this discussion.
Aviatorsmith 6 months ago
Do the other electromagnetic waves slow down when moving through a dense medium?
qwerty657ful 6 months ago
@qwerty657ful All electromagnetic waves are considered light. What we can see is visible light. As long as the medium is optically denser (there is a difference between dense and optically dense), the waves will slow down.
Aviatorsmith 6 months ago
@Aviatorsmith Thank you for answering my question.
qwerty657ful 6 months ago
@Aviatorsmith Do they slow down by the same ammount for example i pass light through a glass block and it slows down to a differnt speed, if i where to then pass X-rays through the same block of glass would it slow down by the same aamount?
qwerty657ful 6 months ago
@qwerty657ful No, they don't; you can see it when a prism breaks up white light into its component colours and forms a rainbow; that happens because each colour (frequency) is slowed down by a different amount, so they are bent by different angles at the interface between air and prism and thus separate.
wtrmute 6 months ago
@ispravljat Yes, your senses do not differ from each other in the way they transmit information to the brain. But they do differ in the types of information they gather. The way your brain processes those signals are not the same.
You can't smell all of the molecules because the human olfactory organ is crude. As I have said, only molecules which can fit into the receptors can be "sensed". We have evolved such that what we can smell are the smells that are most relevant to us.
Aviatorsmith 6 months ago
@ispravljat The sense of smell doesn't differ from other senses. They all take information supplied to the sensory organ and turns it into electrical signals that get transmitted to the brain.
Smell molecules are molecules just like any other. The nose works by taking these molecules emitted by a source and turning it into electrical signals. Those molecules "fit" into certain receptors in the nose. Different smell molecules will fit into different receptors to produce different signals.
Aviatorsmith 6 months ago
@ispravljat The speed of smell is dependent on the amount of kinetic energy the smell molecules or atoms possess, most likely in the form of heat energy. The speed of heat is dependent on how conductive a material is. In the case of He4 at 1.8k, it is around 20m/s. For other materials it is considerably slower, several hundred times in fact.
Aviatorsmith 6 months ago
its "c" for celeritas. Latin word for swiftness. We derive acCELERATION from this.
BassaliskVFX 6 months ago
Its C for cool.
ghostalin 6 months ago
Whoa hold on! What was that last bit? A calculator with the constants on it? I just emailed Sigma Aldrich to try and get them to make one with the periodic table on it, along with things like nomograph functions for calculating new vapour pressures etc. The guy didn't get my point though. I meant a physical pocket calculator, not the online one.
lexichronicle2 7 months ago
@lexichronicle2 I'm sure that could be done (and I'm surprised it hasn't...) with a graphing calculator. You can even load custom programs into it.
JuryDutySummons 7 months ago
Comment removed
LeconsdAnalyse 7 months ago
The C is derived from "celeritas", -atis: (Latin) meaning speed; quickness; and in his 1905 equation regarding the theory of special relativity "c" represents the velocity of light, about 186,000 miles per second. And this speed is the same for any observer in any inertial frame, no matter how one is moving relative to the source of the light, and it is impossible to accelerate an object from below the speed of light up to the speed of light.
xenophonon123 7 months ago 12
@xenophonon123 what about non- and anti-inertial frames? how can it be called relativity when the speed of light is being sold as an absolute value (which is questionable since speed is a ratio and therefore relative by heart). can you tell me one way where i can measure the speed of light on my own and with household materials? you ...
vertexgo 6 months ago
@xenophonon123 ...don't tell the context of the speed of light. it's an open question if the speed of light can be slower than the speed of "matter" (you're typing about moving an object - but what about the object itself if you go to "deeper" and "deeper" scales) and the speed of matter (not an object being moved but the "details of an object moving to make up that object) being faster than light.
vertexgo 6 months ago
@xenophonon123 i expected one of them, when they said "i'm not sure", to say it proabably means someting in Latin which is what i was thinking. Thanks for clarifying
1KevinsFamousChili1 5 months ago
question: what would light "at a snails pace" or for that matter, slowed down to any level, look like? would it leave more of a "trail" or what? :/
FeebleMuffin 7 months ago
they used the letter "c" for the speed of light because its what you SEE!!! C get it? ??? IDIOTS
ianlutz 8 months ago
@ianlutz BOOO!!!lol joking...haha
MrRxProductions 7 months ago
Haa 4:42. That's what i sound like when i don't know what im talking about, but desperately want to
Mizzouslug 8 months ago
why does time slow down when you approach the speed of light?
Shockszzbyyous 8 months ago 20
@Shockszzbyyous Great question. Theory suggests, that time is basically a direction. distance=rate*time right? So basically (you need to open your mind for this one) time spreads at the speed of light. When getting closer to this speed, you *catch up* with time so to speak. That's why reaching the speed of light is impossible. If you reach it, your observing time is zero and thus you can not be moving at all. So time being a dimension also makes it a barrier for other dimensions to cross.
Semikindless 7 months ago
@Shockszzbyyous cuz chuck Norris feels like it
generalpivot1 7 months ago
@Shockszzbyyous Because a material object moving close to the speed of light (in vacuum) DISTORTS spacetime.
LeconsdAnalyse 7 months ago
@LeconsdAnalyse does it have to do with the fact that the faster matter moves, the more massive it get's?
Shockszzbyyous 7 months ago
This has been flagged as spam show
@Shockszzbyyous
Hello. It is because of the metric, ds²=-c²dt² + dx² + dy² + dz² and the definition of `proper time` (τ), dτ²:= -c⁻²ds². The metric may be rewritten as dτ²= (1-v²/c²)dt², with v²≡(dx² + dy² + dz²)/dt². So that, γ(τ₂-τ₁)=t₂-t₁ which is the equation for `time dilation` (γ := 1/√(1- v²/c²)). For example, if v=c√3/2 then γ=2 and, 2(τ₂-τ₁)=t₂-t₁. That is, time ticks one-half times more slowly for the inertial frame in relative motion.
LeconsdAnalyse 7 months ago
@Shockszzbyyous Because light speed is a barrier for traveling trough time dimension.
D3w10n 7 months ago
@Shockszzbyyous why is a hard question to answer but it happens because you HAVE to be able to shine a flashlight forward while moving 99.9% the speed of light and have it appear to you that the light is leaving the flashlight at the speed of light. if time did not slow, relativity would fail.
danthemanzizzle 6 months ago
@Shockszzbyyous Because, since light is the same in every perspective (frame of reference) something has to be changing and that is time. e.g. You're in a train going at half of light and you turn on headlights, you see that beam go at light speed. But if you are outside you will also see the beam of light going at light speed, not speed of light + half of speed of light.
Aweois 6 months ago
@Shockszzbyyous because if you were on a train traveling at 99.999...% of the speed of light, if somebody got up on that train the combined speed would be greater than the speed of light. therefore, time slows down, relative to the speed that an object is traveling. 0mph is the absolute slowest that time can go (although it is impossible to tell if you are at 0) and at the speed of light, time stops to stop anything exceeding it. lol its so confusing :)
Ashcombeguy 6 months ago
@Shockszzbyyous its all relative
bnjmv 6 months ago
@Shockszzbyyous If you are the one travelling near the speed of light, and you are going in a straight line (ie not changing speed or direction) time appears perfectly normal to you. You won't notice any slowing down. Allow me to recommend the following YouTube vid: Search for "Einstein's Relativity and the Quantum Revolution Modern Physics part 1". He explains it beautifully for non-physicists.
wesmatron 6 months ago
@Shockszzbyyous Sorry, forgot to mention, his name is Richard Wolfson. I think he's great.
wesmatron 6 months ago
@Shockszzbyyous
"Space-Time"
EFDragon 5 months ago
@Shockszzbyyous The simplest explanation is that c is your cosmic speed through spacetime. You are travelling through spacetime at c, and always at c, it's yours to spread across the four dimensions. If you use alot of speed to move through the 3 spacial dimensions, then you have less speed left over to move through the time dimension.
russellrummage 5 months ago
@Shockszzbyyous Space Time Fabric.
olivebates 5 months ago
@Shockszzbyyous Time is layed out on a fabrik we call Space Time Fabrik. This fabrik gets bent by gravity.
E=MC^2. So Energy = Mass^2. So when you create the energy from movment, it also adds to the mass. and at the same time, the actual area the mass is filling shrinks. Therefore, because more mass is in the same place, the gravity around that object will be stronger. As you aproch the speed of light, this mass to space ratio goes up to nearly infinite (Hitting the speed of light would mean
olivebates 5 months ago
@olivebates Theres an infinite amount of mass in one place. Witch would be physically impossible as it would collaps the whole univers (probably)). As your mass goes up to near infinite, the gravity will be so strong, it bends the Space Time Fabrik nearly infinitly, meaning time it self will slow down.
Or at least thats how I've understood it.
olivebates 5 months ago
@olivebates Read from the bottom - up.
olivebates 5 months ago
@olivebates This is the same argument that scientists used to say why we would never exceed the speed of sound. In the sound case, the fabric we were compressing was the air in front of the airplane. As it turned out the problem was solved by engineers. The speed of light limit will turn out to be the same case of science versus engineering. It's up to the engineers to solve the problem.
Nomoreidsleft 5 months ago
c comes from Latin celeritas (meaning "swiftness"). Look up speed of light in wikipedia for the history, including what symbols were used for the speed of light before c was used.
pdfdan 8 months ago
c stands for "candela", which is the unit of lightspeed
MrSneppe 8 months ago
Man these people reek of intellect.
kamikrazi123 8 months ago
Comment removed
LeconsdAnalyse 8 months ago
what if you shot light through higgs-mass, who knows might go faster than vacuum
TheDukePuke 8 months ago
Where can I get one of those calculators that he has, that has all the variables? Like c, g, G, cosmological constant...
69MrUsername69 8 months ago
Comment removed
LeconsdAnalyse 9 months ago
Comment removed
elmotouchesme97 9 months ago
so... if it were possible to actully travel faster than light, would you be in total darkness as the light can't keep up?
elmotouchesme97 9 months ago
b/c if it is instant, you could create a gravitational oscillator, say create a mass then destroy it and create it again, if you could make a machine to do this and make a receiver, you would have instantaneous communication.
Gmc42082 9 months ago
heres a legitimate question no one has ever been able to give me a good answer. What is the speed of gravity? not the acceleration, like suppose an object with mass just appeared, would the gravity be instantly perceivable or would it take time like light for the effect to be measured?
Gmc42082 9 months ago
Comment removed
LeconsdAnalyse 9 months ago
Just curious if you could travel that fast, would you be able to look out the window and see if the "light" was keeping up? or would you be unable to see it because even though it was traveling along side of you the delay was too great?
ameiko76 9 months ago
Comment removed
LeconsdAnalyse 9 months ago
Furthermore, the speed of light will never be proved incorrect, zzzIdivededbyzerozzz. The metre is defined as how long it takes light to travel a certain distance. So if anything, the metre will change.
venium 9 months ago
This video is ambiguous in some ways. First light never slows down. It "appears" to slow down through some materials. It is not an absorption/reemission from atoms either, as many people think. It is the vibrations of the electrons of the atoms that create more EM waves that interact with the incoming EM. This interference causes an extremely complex phenomenon. Richard Feyman and the study in QED has the answers.
venium 9 months ago
"c" a big blue wobbly thing that mermaids live in.
DeadButFeelingBetter 9 months ago
Comment removed
LeconsdAnalyse 9 months ago
so when they slow it down. how? do they refract it through something over and over or what? if anyone can answer that...
alip2310 9 months ago
Comment removed
LeconsdAnalyse 9 months ago
Light does not slow down, ever. Light does need to interact with atoms that it comes within a certain proximity of, and retransmission takes 10^-15 seconds to complete. So, roughly speaking, the denser a space is with atoms the slower a beam of light passes through it, but if that beam had a speedometer it would always say c m/s.
Vellwander 9 months ago
3000 km per second. Trip to the moon and back, about four minutes. I hope they find a way to slow down light in such a way it doesn't speed up again when it leaves the material slowing it down.
FHomeBrew 9 months ago
c represents the speed of light because it is the initial letter of celeritas, the Latin word meaning speed.
WhiteCrazyPeople 9 months ago
IM FASTER
jayworthenwhoa 9 months ago
Okay, the speed of light is a universal speed limit. So, how does this speed limit exist at the same time as entanglement? Entanglement is a bizarre phenomenon where two objects communicate their state with each other, instantaneously, no matter how far apart they may be, seemingly breaking the limit of "c." How is this possible? How does it work?
prwexler 9 months ago
c for celerous or smthn like that
playitverysmart 9 months ago
And if his calculator breaks?
MysterMysteryHunter 10 months ago
I am always stunned how fast michael can talk....when i started watching the videos i couldn't follow him...but now i think i like him (well..the way he explains things...not him himself because i don't know him....)
Defonthana 10 months ago
@beerandgirls93 Not really, why?
oskiflesh 10 months ago