Physicist: The best way to think about it is; there is a speed (C) that is the fastest speed and, by the way, light goes that fast. There’s nothing special about light, it’s just a useful way of describing C (“the speed of light”). Photons are just another podunk massless particle, whipping around the universe as fast as fast can be.
Historically, the derivation of the strange properties of C (relativity) relies on a pretty straight forward piece of Einsteinian logic, based in part on an understanding of light.
1) All the laws of physics work the same, whether you’re moving or not. There is no experiment that can tell you whether or not you’re moving.
2) Light is an electromagnetic wave, and the velocity of these waves can be derived from Maxwell’s laws.
3) Maxwell’s laws, like all physical laws, are independent of how fast you’re moving. So the speed of light must also be independent of how fast you’re moving.
4) So, there exists a speed (the speed that light travels at) that is the same to everyone, no matter how fast they themselves are moving. Holy crap! There’s your special relativity!
So when you see equations like 
So why is C the fastest speed? A good way to think of it is to first ask; how do you know when you’re moving faster than something else? If you’re driving down the highway and you’re moving faster than the car in front of you, then eventually you’ll pass that car. However, C is the same to everyone, no matter what. So, say a photon goes past you, and you try to catch up. But no matter how much you speed up, the photon will always be moving away at the speed of light. You can never catch up (or even come close to starting to catch up). So, regardless of perspective, the photon is always moving faster than you.
Some of this may seem seem contradictory, but surprisingly, it’s all self consistent. Very surprisingly.
A related question: Why is C a finite value, i.e. why is it not infinite?
Or maybe another form of the question: is C just a fundamental constant the value of which cannot be explained, or can it be derived from other more fundamental constants/principles?
OK you can say according to Maxwell c = sqrt(1/e0µ0), but this then just extends the question to e0 and µ0
Pretty much. There are many physical constants, and not as many equations relating them, so you’ll always end up with at least a few (19) variables that just are what they are. Your example above is about the best example. Of the magnetic permittivity of space, electric permittivity of space, and the speed of light, which is fundamental? There’s no way to tell for sure, but I cast my vote for C, and the electric permittivity.
Magnetism can be derived from electric forces and relativity, but we could have it backwards, or it may not matter to the universe at all. In practice we have these constants measured, so we just use what we have, and don’t stress terribly on what came first (after all, you can eat eggs and chicken without too much trouble).
Thanks! Also for the subsequent post 🙂
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Hi. This isn’t exactly related to the post, but regardless, I’m perplexed. What happened in this experiment that the scientists claim they’ve sent light faster than c? Is there no “universal speed limit”?
http://www.cbsnews.com/stories/2000/07/19/tech/main216905.shtml
This is pretty tricky, but it comes down to a distinction between “phase velocity” and “group velocity”. Without going into detail (a long post) the experiment essentially requires a “standing wave” with waves at many wavelengths. These waves interact in such a way that they create peaks, like when you pluck two slightly-out-of-tune guitar strings and you hear a pulsing sound.
These peaks move around in the standing wave region, and you can more or less keep track of where they are. In the middle of the region is a specially constructed cloud with extremely weird optical properties, that changes how fast light of various frequencies move through it (slowing only, but to various degrees).
By changing the different frequencies you change how the peaks move around (making them faster than light in this case), however nothing is actually moving faster than light, just a non-information-carrying effect.
Another example of this sort of thing is the “scissor paradox”. When you close a pair of scissors the point where the blades intersect is moving much faster than either blade, and if you were to construct a pair of scissors large enough then the point of intersection would move faster than light, but it wouldn’t be able to carry any kind of information (in part) because you’d already see the slower-than-light blades moving long before the intersection point got to you.
This pulse thing is a similar “paradox”.
Hmm… kinda crazy. And cool. Thank you!
Update! The long reply above has been expanded into a post:
https://www.askamathematician.com/?p=4037
Ok, this might sound a bit quirky, but how did Einstein really did get to know or derive or arrive at the conclusion that the fastest achievable speed is the light speed ? (1)
(2)Well, he had a little doubt that what would happen if he were to travel next to a photon at its own speed. Let us consider that I can travel at the speed of light, even if relativity doesn’t permit me to. Then travelling next to a photon at its own speed, will I be able to see the oscillating electric and magnetic vibrations?
There were a series of experiments, most notably Michelson-Morley, that demonstrated that the speed of light seems to be the same regardless of how the experimental apparatus is moving. In the case of Michelson-Morley, they waited until the Earth was in different parts of its orbit (and thus moving fast in different directions), and even did the experiment on a boat so they could move around at will.
The result was ultimately inescapable: the speed of light is the same regardless of how you’re moving. As a result, as you speed up, you’ll find that light is still passing by at the speed of light. You can never even get close!
example there is an infinite abyss then I throw a thing (like a piece of chalk) then it falls faster and faster. Is it possible to surpass the speed of light? then if it is possible, if I fell myself in the infinite abyss until I surpass the speed of light then i can travel through time? (by the way I’m just a kid and i just want to know those things XD )
Am I right vision speed is faster then light
Speed of light is not relative to speed at the observer is moving .
In your words, ” the speed of light is the same regardless of how you’re moving. As a result, as you speed up, you’ll find that light is still passing by at the speed of light. You can never even get close!
”
I have a problem here :
If I am moving at speed , say, 1.0 * 10^8 m/s , and observing a speed of a photon.
Myself and the photon started our journey at the same point.
So, normally , I must observe the speed of the photon as 2.0 *10^8 m/s .
But, according to special relativity, I see the speed as 3.0 *10^8,
Then, I must say that “Real” speed of light or abstract speed of light is 4.0 *10^8 ?
If I go ahead, I will find speed of light as infinite in nature?
Were the greeks right in saying Speed of light is infinite?
Is the value ,3.0*10^8, is a relative one ?
The speed of light is always that same 3*10^8 m/s. If if you happen to be moving for someone else’ perspective, you’ll find that you always feel stationary. Photons always pass at exactly the same speed, both for you and for who ever thinks that you’re moving. It turns out that velocities don’t add the way we intuitively feel that they should. There’s an old post here about that here.
We can demonstrate it, but we still can’t explain why c = 299792,458 km/s. If we could experiment the universe travelling like a photon, it would be truly weird. Being massless and travelling at c, the whole eternity of time has passed in no time for your single experience. So you’d be standing away from the concept of time. Also, space would have shrunk enough so the whole universe would be infinetely small from your point of view. That is, you’d be everywhere in space, reaching any point at every time. That is, if you are massless. If you happen to have even a tiny amount of mass, then you’d also be infinitely dense and massive at c, perhaps shrinking all the mass of the universe in a singularity, like reversing the big bang.
Of course, you would require more than the energy in the whole known universe in order to attain c being massive. Perhaps the big bang is what happened when energy “decided” to slow down and become massive
After reading all the comments above the question of why the speed of light is the fastest thing in the universe has not been answered. The only thing for certain is that the speed of light appears to be constant.
In Einstein’s postulates for the theory of Special Relativity he make a conclusion/assumption that the speed of light is the fastest thing in the universe, but failed to prove it experimentally or otherwise.
In fact no one yet has been able to actually prove it. Einstein would have been better of saying he thinks the speed of light is the fastest thing in the universe.
However that wouldn’t work for his theory. The problem with physicists and scientists is that they sometime accept these assumptions/statements as being 100% true and don’t challenge them. Maybe because it you can’t disprove it, it must be true.
This gets into the question, why is there this general conception that the speed of light is a limit on how fast ANYTHING can travel. I haven’t thought of a good way (so far) to express this, to show a reason not to believe this, but I think the idea that nothing can go faster than c, the speed of light, is ridiculous. First of all, you have to understand, there is no such thing as an absolute speed. All motion is relative to something. Speed is a measure of how fast something is moving relative to something else.
“The motion of a body can only be described relative to something else – other bodies, observers, or a set of space-time coordinates.” – http://en.wikipedia.org/wiki/Inertial_frame
An object in outer space does NOT have a speed. It has a speed in relation to other things. Every object in the universe could be said to have almost an infinite number of speeds, because there are an almost infinite number of other things to move in relation to. So to say that an object cannot move beyond the speed of light, that necessarily means you are saying that there is no thing in the entire universe which is moving at a speed faster than c in relation of this object you are talking about. When you talk about going faster and faster towards the speed of light, people think you are in this spaceship and the speedometer needle is rotating to the right more and more, but is slowing down as it approaches this RED line which indicates light speed. They think your space ship is going to start shuddering as you approach c, because you are going SO DAMN FAST! And the space ship is ready to explode or something. Your mass is increasing to infinity! Your time is slowing and slowing. The length of the ship and everyone in it is contracting and contracting, as per Einstein’s equations. But in reality, as I’ve said, motion is relative. If something on the other side of the galaxy is moving away from us here on earth, at a speed approaching c, then we are also, moving away from that object at a speed approaching c. So right now as you sit here reading this, you may very well be moving at a speed (in relation to another object in the universe, which is all speed is) that is close to the speed of light. Do you feel you are highly massive because of this? Do you feel your time is highly retarded? Do you feel you are thinner in one dimension than normal? No, you feel just fine. Oh, but the believers in special relativity will tell you, you aren’t going to feel these effects. Its only the people on that other object on the other side of the galaxy as they look at you on your planet earth, they will see these effects, such as your time being slowed down in comparison.
Lets say you are going on a journey to another star, that is 4 light-years away from here. And let’s say you know the alien beings living on a planet orbiting around this other star, and you have sent them messages and talked with them. The aliens on the other planet (we’ll call it planet B) have decided they are coming to visit earth. We have shared technology and we both have a spaceship that can approach the speed of light (in fact, let’s say they sent us their plans so we have both built identical space ships). We both launch our rockets and start speeding towards each other’s planet. Both our ship and this other ship are now moving at .9 times the speed of light. By the way, let’s say that planet B’s sun and our sun are both still with respect to each other. So lets imagine a huge inertial frame in space that includes these 2 stars. That will be like an objective inertial frame over which these space ships will travel. When the 2 rockets, one from earth and one from planet B meet in the middle, they are both going .9 c with respect to this huge inertial frame that includes the 2 stars. Looking down on this inertial frame from above, the 2 spaceships are approaching one another at a speed of 1.8 times the speed of light. Now, in my view, that shows that things CAN travel at a speed greater than the speed of light. Because ship A (the one from earth) is moving with respect to ship B at a speed greater than light. But the special relativists will say, no, that’s not how you do it. We are talking about the speed that ship B will be perceived to be moving in relation to the inertial frame defined by space ship A. They give you these Lorentz equations and say, see that’s how you calculate the actual speed that passengers on ship A will see ship B as moving. Because of the relativity equations, you will see the ship is NOT moving (in relation to inertial frame based on ship A) at a speed greater than the speed of light. From ship A, if they look at ship B, it will be shortened in the direction of travel. The mass of ship B will be way up. The ticks of a clock on ship B will be way slowed down from those on the observers on ship A. But are all these effects really happening to ship B? Or are they just distortions based on the great speeds that are being attained between the 2 ships. I think if these effects actually happen as anticipated by the special theory of relativity, then I would say if anything they are distortions of perceptions from one ship to the other. If you really want to see whats happening between these 2 ships, you move up off the inertial plane which contains the 2 stars and the 2 star ships, and from that vantage point, you can see that the ships are approaching one another at a speed of 1.8 times the speed of light. So, I think what you want to do is, remember, that when you hear scientists and journalists talking about this idea that nothing can exceed the speed of light, what they really mean is that, no observer will ever directly measure some object or wave or whatever, moving at a speed greater than the speed of light. However, as I’ve shown, things can move with respect to other things at a speed greater than the speed of light, looked at from an objective point of view (or at least a more objective point of view than directly measuring objects’ speeds relative to the observer on another object he is observing from). The people on ship A will see time slowed down on ship B, but they will know that this is a perceptual distortion based on their moving past ship B at a very high rate of speed. They know that ship B’s ship has not really shrunk. They know ship B’s time is still ticking along as it always has been, from before the space ship took off. They know its mass hasn’t really increased (I wonder if special relativity predicts that since the mass of this object moving near the speed of light has increased substantially, would this cause their space ships’ path to actually be deflected more as they passed each other because of their masses bending space?). They know these are all distortions caused by fact they are moving with respect to each other at high rate of speed. But they know in reality both ships are the same. And if you look at things from objective point of view, they are approaching each other faster than the speed of light. Aha! So there! And remember, there is no such thing as absolute speed, right? There is only speed in relation to something else. And if you are flying in a space ship to another star system, it is perfectly reasonable for you to have a speed in relation to another space ship also flying to your star system. And thus your speed in this case is a speed that exceeds the speed of light.
Notice that throughout this whole thought experiment, I am living within the constraints laid out by the special relativity theory. And still I came away with one object moving faster than the speed of light in relation to another object. And remember, that is all that SPEED is, it is motion per time in relation to something else. People talk about not being able to exceed the speed of light, like outer space is the big 3-D grid and everything is just sitting there in this grid and moving in relation to this grid. Well, that is old Newtonian thinking. Now, its true that I am sort of trying to critique the new Einsteinian view of things, but I do believe that there is not some absolute grid underlying space or something like that.
(I have nothing but intuition and metaphor to go on here, but…) Could speeds beyond C be like an unattainable ‘escape velocity’ for information, mass or energy, at least metaphorically speaking? Could C be one aspect of a ‘nonlocalized’ boundary of spacetime, such that if it were possible to exceed this limit at any point or time, spacetime would be exceeded (or perhaps more accurately, the object/event in question would cease being able to exist)? As one other commenter mentioned, this would require more energy than exists in the universe, but is it at all useful to think of C not merely as a cosmic speed limit, but associated with the ultimate bounds of existence/relationships within spacetime?
why only electric and magnetic fields can form light ? are we sure that there are only these forces in universe that are known?in universe nothing is known to be finite how number of forces can be finite ….i mean why only gravity,electrical,magnetic……..etc(finite)
Phaedrus is good. All speed is relative to something. A photon in a vacuum has no speed, just frequency/wave-length. Time and distance are inter-related thoughts. Light going through water or passing close by a planet is ‘slowed’ or ‘going further’ . Perhaps time IS distance. Someone said to me “You mean yesterday is another place, same as Australia”. The Aussies will go mad. It should have been “tomorrow is..”
Phaedrus:
You blew me away! I do believe in ghosts!
An extension of this would be on the force front. The speed of light is finite and light interacts with matter. If there exist other elementary particles. (Neutrinos be offsprings of it and matter) that do not interact with matter, it could possibly explain a lot more about both gravity and much more about the universe. Your view on this domain could be revolutionary!
“Sanity is not truth. Sanity is conformity to what is socially expected. Truth is sometimes in conformity, sometimes not.”: Pirsig, Zen and the Art.
Phaedrus:
You defined speed very accurately. I couldn’t agree more to that. Now, the only thing which is wrong with your assumption, is that light/photons behave the same way. It is ridiculous to think about, I myself find it ridiculous, but it has been demonstrated by physicists that LIGHT doesn’t behave in the same way as matter. The speed of light is NOT relative to other moving objects. The speed of light is the same whether you travel at speeds close to the speed of light. Let’s say for example, you are travelling at 0.5C or 1.5 x10^8 m/s. If we treat light as the same phenomenon as those entities possessing mass, the speed of light relative to yourself would be roughly 1.5×10^8m/s. But ridiculously, even if you travel at such speed, the speed of light relative to yourself would still be 3×10^8m/s.
This property of light is the foundation of time dilation and length contraction. Say for example you are travelling at 1.5×10^8m/s in the direction of a photon travelling next to you. You will see this photon still travelling at 3×10^8 m/s. How can this happen? Of course relative to you, the speed of that photon would be 1.5×10^8m/s. BUT, your time would slow down to accommodate this phenomenon. In order for you to still see the speed of light travelling at 3×10^8m/s, your clock should tick only once every two seconds so that when you see that light travels @ 1.5×10^8m/s relative to you, your clock has ticked only half the time it should have ticked when you were stationary. The result? Time dilation. Time dilates to accommodate this phenomenon. Time slows down so you would see light travel half a distance and also half the time when you were stationary. Thus, the speed of light is conserved even if you are moving.
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Do photons experiences time or do they experience zero time?
Nope, that one I won’t agree to. Light does not slow down, it’s a constant. Exchange ‘c’ for a clock represented by it, split into Planck scale. Then that’s your local clock. If you now want to argue that this clock have different ‘clock rates’ you soon will find yourself in a quagmire, invaliding most constants I know of, at least any that are in any way dependent on ‘c’ being ‘c’. Doesn’t matter if you define it ‘globally’ as in it being a ‘commonly agreed on universe’ represented by for example Lorentz transformations, or if you define it strictly locally. ‘c’ must be ‘c’ for us to have repeatable experiments, that is if you define those as being the same, although at different SpaceTime positions.
Defined my way 🙂 ‘c’ is what ‘ticks’, everywhere. It does not have to do with a ‘common universe’ at all. It’s a strictly local constant that gives us repeatable experiments. That’s why you also will pass that ‘event horizon’, locally defined. You have to go the ‘eye of a God’ to get to this ‘global representation’, and that one is still not found. You can though, turn it around. Doing so you will need something giving us a ‘common universe’, but you will win a universe locally free of time dilations and Lorentz contractions (ideally defined, then again, give me a example thats not ‘ideal’)
Actually the last one ask you what you think a consciousness is 🙂 Ever heard of point like particles? To get to this ideal definition of a local ‘wrist watch’ you have two choices, either consciousness also must be ‘point like’, or it is a result of communication (information flow). Or it could still be both actually. Yeah, life is weird.
Does electron,proton and neutron have a sub particle?
With all the theories and words written about the speed of light… the question…why is the recorded speed of light what it is…what effect causes it to be what it is … why is it held back at the maximum speed of 186,000 mps…is space filled with a substance we have not discovered yet…a substance that retards anything that goes faster than 186,000 mps…for instance…dark matter which is accompanied by dark energy… THE SPEED OF LIGHT NEEDS MUCH MORE INVESTIGATION IN MANY MORE WAYS !!
@Ashik Shalin: Protons and neutrons do have constituent particles (they’re called quarks), but electrons do not.
It is true that the term speed of light is a way to say light moves at 186,000 mpsec same as I might say my car will do a mile a min…however I can tell you why it will do the speed of a mile a min… light is just one of many things that move at 186,000 mpsec … all electrical functions move at that speed etc…THE FACTS ARE…THAT NO ONE HAS ANY IDEA WHY THIS SPEED LIMIT EXISTS !ONE THING FOR SURE…THERE IS A REASON ! IT HAS NOT BEEN DESCOVERED YET… but it will be !!in 10yrs…100yrs…1000yrs…10,000yrs but it will be discovered !!!
I have an intiution that the existance of magnetic monopoles may explain the spped barrier. Anyone can help me out????
“There were a series of experiments, most notably Michelson-Morley, that demonstrated that the speed of light seems to be the same regardless of how the experimental apparatus is moving. In the case of Michelson-Morley, they waited until the Earth was in different parts of its orbit (and thus moving fast in different directions), and even did the experiment on a boat so they could move around at will.”
Most notably Michelson-Morley?
So, our best proof that the speed of light is maximum is a couple of guys in 1887 with some mirrors on a boat comparing measurements/results?
Once we accept that the speed of light is constant, everything else follows: dilation of time, contraction of space etc., but that is just a mathematical consequence, it’s not proof.
Most of the comments above insist that the speed of light is constant, but they offer no proof.
Even if we didn’t observe something faster than light yet, it doesn’t mean it’s not possible.
@john l mccowen
Dark matter is not really matter per se. It is not the kind of substance that would have the friction force to slow down light. However, quantum mechanics have confirmed that that empty space is indeed not empty in reality and that there is a substance to it. That may not be enough to explain the speed barrier since the mechanics themselves are based on the barrier.
@Marius D
There are many more experimental observations that confirm that the speed of light is constant. Now, I see that you claim that observation is not enough to prove something. If that is your stance, then you are simply invalidating science altogether since science is based on observation. And in that situation there is no discussion to have because it makes absolutely no logic to have a debate without scientific principles if the debate topic is of course regarding science.
It was never stated that objects faster than light do not exist. Tachyons have been proposed. The speed barrier states that no object can accelerate up to the speed of light, and the consequence for this is not so much mathematical as it is physical (the mathematical consequence only exists because of the physical properties, not backwards).
I was just wondering but is there any way to essentially speed up light? Like is there a way to charge up a regular photon so that it goes faster than its original self?
Quote from above:
“The speed of light is always the same 3*10^8 m/s.”
So speed is a measure of distance over time. It is about “per second”
I think it is not about the speed of light, it is about the speed of time.
What the speed of light shows us, is how fast time can move.
Time can move quickly enough to “show us” a photon traveling 299,792 milometers in one single second. But no faster.
Things can change no faster than that.
So in the case of light, no matter where we are, or how fast we are moving, we can see the photon move no faster than the speed of light, because that is the fastest rate of change that can be represented. Or put another way that is as fast as time can go.
Gus Harrigan,
Inaccurate. Time has no speed. Time has no speed because it traverses no distance, no space. It is not a wave nor a particle. It is not an object. Not to forget that time is relative to the observer, according to special and general relativity, of which the former is a special case of the latter. Therefore, the idea that the speed of time can be measured objectively from any reference point and be equated to the speed of light is bogus and absurd. The speed of light simply arises due to causality: it is the rate at which causal relationships can be manifested and observed.
Caleb Salem,
No, light cannot be sped up. In order for acceleration of a particle to be possible, such particle must have a rest mass, which photons lack.
Ángel Méndez Rivera : Thank you for your reply. First I should say that no one should answer a test question with what I am saying about time. Maybe I should have been clearer about that because I am in no way claiming my idea is a fact here. I am only saying what I think may be true.
Second, I apologize but I am limited by language when I use the word “speed”. I do not intend it to be referring to velocity or rate of movement over distance. I will use speed to mean velocity henceforth in this discussion.
What I mean to say is that I think there is a maximum rate of change possible in our universe. I would like to call that Time for now if I may.
Using more imprecise language I will say that I think the “machinery” of our universe, the system, can only change up to a maximum rate. And I think that maximum rate is observable when we see that light can move at a maximum speed and no faster.
Again please allow me license with language in order to convey an idea (that may or may not be true) that the rate of change of anything has a maximum that is dictated by how “fast” the underlying system of the Universe can accommodate change.
Let me call the rate of change “Time” please. So I am saying I think Time can only move so fast.
As you point out the speed of light and time are relative to the observer. Which is very difficult to understand intuitively (at least to me).
If I may be excused to even use the term Thought Experiment for what follows, I would like to try and describe one (imperfectly) and see what you think.
Let’s say that the Universe is a machine that has a maximum rate at which it can operate.
Let me say that a photon in a vacuum will travel as fast as it possibly can.
So, the machinery of the universe can only run so quickly, and a photon in a vacuum will travel as fast as the machinery of the universe allows.
Now when I am observing a photon, no matter where I am, or what my relative velocity is in any direction, I always see it moving at the speed of light, perhaps because that is as fast as the machinery of the universe can possibly show it to me.
To me that scenario is not too different from what we are observing about the speed of light and relativity, unless I am missing some major understanding.
I was calling that maximum speed of the machine of the universe “Time”. Maybe I need a different word but if there is a more proper word for it, I don’t know it.
To me it is a more easily grasped concept to say that I always see light moving at “C”. no matter what, because that is as fast as “Time” can go.
I wouldn’t expect you to agree with me but please let me know if I have been able to convey my thought in a way that makes better sense this time. Thank you. Gus
You conveyed your idea properly, but I still have to strongly disagree. You cannnot call a rate of change “time”. The units don’t match up. And it’s highly misleading. Time already is defined as something else. Seriously, there are hundreds of better terms out there you can choose to use to convey your idea without using misleading notation and abusing from terminology.
All the things you say are true… with what we now about TSL seems to be true…you have skillfully displayed all the knowledge there is about TSL…however, there are several areas that needs to be investigated…how are photons destroyed ? At this time there is no explanation of TSL that will completely satisfy the human mind…You must remember Aristotle said the earth was the center of the universe and this was the truth for many century’s…
John,
1. The difference between geocentric thought and the theory special relativity is that special relativity was shown scientifically, whereas geocentrism stemmed from religious thought.
2. Photons can’t be destroyed due to conservation of energy. Also, photons are quanta.
Time and TSL are two things…
Thank you John. I have some ideas I am working on having mostly to do with my own understanding of things. By which I mean, I am not trying to propose, suggest, or otherwise annoy the physics community 🙂 Especially since I need the physics community because I need to know some things.
My main pursuit now is to talk to people who can help me with this:
C =299,792,458 m/s
In that representation the denominator if it can be called that, is in seconds.
It is per second and I think to talk about speed, we have to also talk about time for that reason.
I am hoping to talk to people who can understand more about the /s, or second, in C. As far as I know we use a second that is referenced by the decay of cesium.
I will get better at stating my question as I go along, but for now the best I can do is to ask: Is there any way we could know if, in an absolute sense, the unit of measure the second, had changed at all over billions of years?
Put another way can we know if a second now, is the same interval, as it was 10 billion years ago?
There is a reason that there is a limit to how fast anything can move in space…there is a good reason… no one has discovered the reason to date…everything we know of and about is immersed in the median of what we call space…we do not know if space is a fluid, gas, solid, light, dark, heavy, thick, thin, hot, cold, yet we live in this thing called space…even though we have no feeling for or of the substance of space around us…it would seem to me that space may be constructed with a substance that retards anything that reaches 186 000+ miles per second… Question?… what happens to a photon when it reaches max speed ?
John l McCowen
Your description isn’t inaccurate for various reasons.
1. There IS a reason for why there is a cosmic limit of speed, and we DO know the reason. The answer lies within causality.
2. The universe is dark and cold. We know this. We also know it makes no sense to talk about the universe being solid or gaseous.
3. A photon does not reach max speed. Photons do not accelerate, photons are never at rest. Photons ALWAYS travel at the speed of light, and it is the only speed they can travel at.
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I too was thinking about the maximum speed of a photon or light ray, I pondered and wondered about the speed limit of light C, I was thinking that ” Why the light cannot travel faster than C or slower than C”, I was not wondering about any other thing which can travel faster or equal or less than the speed of light, I was only thinking about “Why the Light has a fixed speed at all” ?,
Then I too arrived at the same conclusions as Mr. Gus Harrigan has arrived in his above comment, I agree with him, because he has written my thoughts in his words,
I was thinking that the universe has a rate of change speed, that is equal to the C, in my opinion I was thinking that the Universe creates the Space with the speed of Light i.e. C, therefore the maximum speed available for a photon to travel is C, this was in my opinion, I was thinking that the universe constantly creates space with a fixed maximum speed of C at any given moment, and this is the maximum rate of change available in the universe, Therefore I reached the conclusion that the Light travels with that maximum allowable speed.
No, none of that actually makes any sense. The universe does not create a space at any particular speed because that type of rate of change is not a speed. The answer to why light is the fastest speed actually has to do with the very nature of what E/m is confined to.