# How to have light move faster than C

Ok, I have an argument for how light must exceed C from a time dilated frame.

And the time dilation in this is all general relativity, and the way time slows in a gravity field, and that this also applies to G-force (inertia) due to the equivalence between acceleration and gravity.

But first a few dry runs…

First let us make a light speed measuring device with 2 light sensors (A and B) that are 1 meter apart (or whatever distance is required by the state of technology to measure light speed accurately, 20km or 20,000km would also be acceptable), but we will have 2 high resolution clocks, the signals from light sensor A goes to both clocks, as do the signals from light sensor B.

The 2 clocks if they are both working correctly will measure the same period of time between a photon hitting sensor A, and then sensor B.

Note: If you want you may skip ahead now to the lines of hyphens that reads “The Actual Experiment” and read from there, but if you have any objections it might be best to read the rest of the dry run section below:

BUT we are going to suppose that one of the clocks is faulty so that it measures less time between these 2 events.

If we did not know of this fault, we would have the curious answer that the speed of the same photon travelling between the same 2 sensors moved at C according to one clock and exceeded C according to the other clock.

But this is in no way interesting you say, the clock is just wrong, and of course you are right, the clock is simply wrong.

Next we replace the faulty clock with one that has been fully checked out to be good, and we repeat the experiment, but we place this second clock (only) in a time dilation field somehow (artificial or highly localized gravity field, or centrifugal force, or magic).

This time we should get the same result, the time dilated clock has not measured as much time pass between the signals, it tells us that light is exceeding C between the sensors, the same light moving between the same sensors that communicated the same signals to the other clock that said the speed of light IS C.

But this time the clock is not incorrect in the time it keeps, but it is experiencing time (due to GR time dilation, or magic) to be slower than the space between the sensors.

This would be similar to falling into a black hole and seeing a distant bright pulse of light illuminate dust particles, from your time dilated perspective that is faster than the light should be moving, but not in any way interesting, because of the time rate difference between you and the light.

Ok, so far I still have not said anything even vaguely interesting, sorry about that.

The Actual Experiment:

We will now look closer at those 2 light sensors, they are shaped like CD’s (have a hole in the center for mounting) and are transparent for light to pass through, so making sure the holes are aligned at the same distance as before, we rotate them in the same fashion as 2 CD’s would if you stacked 2 CD drives on top of each other and then separated them to the 1 meter (or 1km if you rather) distance, keeping the axis of rotation of both sensors aligned.

If we let them rotate fast enough that time slows for these sensors due to GR’s time dilation from acceleration, enough to be measurable. And we have one of the clocks rotating with the sensors, and one of the clocks not on the rotating frame.

Now we have the sensors detect the passage of the same photon, no not the same photon as in the previous experiments, we will splash out on a new one! (sorry couldn’t resist)

The signal is split as before with the signal from sensor A being both communicated (possibly by a commutator, or perhaps it is fibre optic) from the rotating rig to the non rotating clock, and to the clock experiencing time dilation as the sensors are.

Sensor B is connected in the same manner to the 2 clocks.

So what should we have as the result?

The light hits sensor A, the time dilation slightly slows rate at which the signal moves to the clocks, one half of the signal gets sent to the normal time clock, and the other half gets communicated to the time dilated clock, it will take the signal slightly longer to get to the time dilated clock since the signal is slowed the whole way. But this does not matter as it slows down the signal from sensor B to the time dilated clock just as much.

So while the time dilated clock will obviously measure less time between the 2 sensors being tripped, the delay in propitiation will not interfere with the separation between the 2 signals, just add an equal delay (assuming equal length paths to the clock) to the reception of each signal.

Ok, so we can agree (I assume) that the rotating clock has measured less time passing between sensor A and B being tripped than the non time dilated clock will have measured.

This means that either the time dilated clock measured light to be at C, and the non time dilated clock measured light to travel less than the speed of light, slower than it can justify.
-Provided of course we are doing this in a vacuum and expected C in the first place.

Or because the space between the 2 sensors isn’t rotating with he sensors, and neither is the photon source, we may assume that the results for the non time affected clock will match the obvious results of the earlier thought experiments.

Additionally if the rotating sensors make such a big difference to the measured rate, then we could have a non rotating pair of sensors (A2 and B2) almost touching the rotating sensors like this: A|A2------------------------------------B|B2

If the rotating sensors really change the measured speed of light for the non time dilated clock, then we would expect to find that sensors B and B2 trigger at notably different times, not as you expect which would be indistinguishable from simultaneous unless you have really mastered measuring vanishingly small periods of time.

Yes, they would essentially have to be measuring different photons not to see both trigger at the same time.

So it seems certain that it is the time dilated clock that sees the light as moving faster than the speed of light.

But it gets worse, if we for a moment pretend it is linear motion not rotation, then if you were moving with the sensor, or not would change your view on the path light takes.

If you move with the sensor, because you are moving at right angles to the path of the light your velocity bends the path of the light so that instead of going straight between the sensors, from your perspective the light is on an angle and hence has further to move to traverse between sensors A & B.

Back to the rotating frame, the light would seem to be spiralling from your rotating perspective making for a longer path, and since a lot of rotation consists on instantaneously linear motion this longer path view is perfectly valid.
If it weren’t valid then motion wouldn’t be relative, if motion is relative angles must change.

So you view the path the light takes as longer, and you are measuring less delay (due to your slowed experience of time) between sensor A and b being triggered!

You are now seriously measuring light be be moving a lot faster than the speed of light, it is completing a longer course in a shorter time!

That would actually still be true even if you believe that sensor B and B2 do not trigger almost simultaneously (detect the same photon in essentially the same position at 2 very different times).
Actually the rear sensor B2 would in that case detect the photon long (comparative speaking) before B does!

Because remember the light has a longer path.

So now you would need the light to slow down in it’s journey between the 2 sensors from the non-rotating frames point of view even more if you want it not to exceeds the speed of light in the rotating frames point of view.
It must slow down so that it makes up for both he time dilation and longer path that from the lab frame isn’t the loner path.

This means that sensor B2 has to trip even more before sensor B. Despite sensor B being slightly closer.

So did I just discover time travelling light?
Make light that exceeds C (at least according to one perfectly valid POV)?
Discover that motion isn’t relative?
Discover that GR acceleration time dilation isn’t logically consistent with the speed of light always being C?
Break Special Relativity with General Relativity?
Discover that a photon may be detectable in one state of motion in a certain at a certain location, but be not detectable in that same moment in that same location with a different state of motion (not just motion actually, but acceleration).

Also while I selected this form of the thought experiment since it is maybe easier to grasp the anomaly, rotation is not required firstly vibration could produce the same anomaly if violent enough to create strong G forces, and this would give the light a zigzag path relative to the sensor POV.

Additionally it could also be performed in a linear manner across a quickly accelerating train with sensors put on opposite windows, the G-forces would create time dilation, the motion would give the light shot directly across the tracks (from the ground) a slant (actually a bend! like light being bent by gravity) from the trains accelerating perspective.

One clock on the train, one on the track under the train with signals from the window relayed by brush contacts, or fibre optics.

Yes SR would also expect that further time dilation be heaped on the rotating frame (or train frame) since it has instantaneous linear motion relative to the lab frame, making matters worse still! (and producing various other paradoxes)

A few words to reduce useless replies which help no one:

I want replies, but a lot of bother can be avoided by not selectively reading things.

And this is a thought experiment that is perfectly plausible to at least work out what Relativity should expect to happen. I tried to cover all possible conclusions, but if you think I missed a set of conclusions that have this make sense, do not object, correct!

Instead please tell me (for all parts of the experiment) what should occur and why that result doesn’t break various parts of Relativity.

Additionally please avoid making any objections that cover only the rotating example, or only the train example, an objection should probably cover all 3 examples to be valid, or if not, then different objections should be presented for each of the 3 forms of this experiment.

Finally, it is not wrong to disprove a theory even if you don’t have an alternative, if a theory is wrong then it needs to be acknowledged that it is broken, and like anything broken it either needs some very real repair (alterations) or it needs to be thrown out and a replacement looked for (or a replacement looked for so you can throw it out for good).
Furthermore there is a perfectly fine alternative that as far as I am aware fits all the evidence for Relativity even better than Relativity does and is easy to understand, logically consistent and has no paradoxes and is falsifiable. But let’s stick to one thing at a time.

Oh, and I am aware that light speed the a constant is an Axiom of Relativity and not explained, but if it is a provably impossible one, then the whole theory must be thrown or altered out if it’s axiom is obviously false, at least if you think science should be connected to reality or truth at least vaguely.

I got about halfway through and then got my dick stuck in the ceiling fan.

Oh, and if you think that it is just fine that the speed of light is measured to be faster than C by the time dilated sensor just as it was in the dry run, no different…

Then it must be realized that due the the longer path light is seen to be taking from the rotating or train frame, that even if we discount GR time dilation the longer path still makes is take longer in the case of the train moving at a constant velocity relative to the track side equipment for emitting and timing everything.

As far as I can see (prove me wrong if you can), all that could be done is to:

To accept Relativity is flawed as it is.
Ignore this and make jokes and knock over incomplete or strawman versions of my argument, or make poor/false arguments.
Challenge everything in an inconsistent manner
Insist that Relativity is just fine being paradoxical and that you make a habit of believing 6 impossible things before breakfast.

And finally maybe you could argue that as illustrated by the dry runs, the light being seen to exceed C by a slow clock is ok, and ok for it to be seen to exceed C in the train due to the slow perception of time that light is not caught up in. (sorry, I am repeating myself)

Of course this would not entirely help because the path is longer making only the time dilation
(indeed only the portion of time dilation caused by GR) to be possibly forgiven, it would still exceed C once that was taken into account.

But if there is equivalence between gravity and acceleration forces…
It would mean that a gravity/g-force time dilation influenced observer would see light travelling faster than the speed of light should be in a gravity field too, the light from a dropped torch should seem to the observer standing in the same space as though that light is moving superluminally. (I am not sure if the dropping would even be required).

So if light travels at full speed though GR time dilation from an non-affected view point (or at minimum can if it isn’t resisting the pull of gravity) then while light might be bent by gravity, it would not be slowed by gravity and would appear to be normal from an observer that is outside for for some reason unaffected.

The next point is this…
If the clock on the track is not effected by the time dilation of the mass accelerating near it…
Then that clock is similar to an object falling into gravity and not resisting it, no?

With gravity it is like we are constantly moving and accelerating as we stand on the ground.
So if you do not resist gravity, but fall, it is the same as standing by the tracks…
Which means someone falling into a black hole would not experience time dilation at all!!! (if we take equivalence seriously)

Not until they stopped falling and felt the gravity of the black hole (as we do earth’s gravity!

I guess you could also say that Relativity is not meant to be understood by the puny intellects of anyone but the high priests of science and so we shouldn’t worry our pretty little heads about such things.
Just listen to what they tell us and not question the almighty and sacred word of Einstein’s 1905 text.
It’s science, it doesn’t have to actually make sense or explain things.

Just postulate impossible contradictory things for no reason, in favour of ideas that would make perfect sense.

And if a mistake has pulled wool over everyones eyes for so long, how can we let anyone know we are on the wrong track now?

Or maybe I am wrong and someone can explain how it works and makes sense.
But if not, then should this discovery that SR is wrong just get lost in this thread?

Call me crazy, but submitting to a peer-reviewed scientific journal is a pretty neat means of doing stuff like that.

I knew a guy just like you in college.
He was in love with his own mind, too, and thought he knew everything.
He flunked out of Physics.

Post Of The Year

(I know, it’s only Feb., but this one has staying power!)

There’s been quite a lot written about relativity in the case of rotating discs - are you sure you’re not ignoring any of that? (I think it’s better if you check, because I couldn’t wring the meaning out of that long description - sorry)

lets see - ‘C’ is the ‘speed of light’ and your proposing that light can go faster than light, I see.

I think they call this ludicrous speed.

Now just imagine the tip of your chopped off weener stuck to the outside edge of one of the blades.

Then imagine that this ceiling fan is the diameter of the Milky Way and is spinning such that your mangled junk experiences 1g of centripetal acceleration, or less.

Well what if there was someone else’s severed peen on the blade directly opposite yours? Would this cause gravity to flow backward in time or would the inertial reference frame drag general relativity like a train?

Does it matter which way the fan is spinning that makes no sense but what if, just what if, it does but it doesn’t? If you’re reading everything I written and not some or just parts not all!!

Keep in mind the aether is also going both faster and slower than Bob’s but also not Alice’s paradoxically before it happened in the future and that’s why I have proven the whole thing is a fraud?

You must tell me the answer, I am only asking the question.

Actually, no. c is a physical constant; light just happens to move at c in a vacuum. Light in other mediums like air and water moves slower than c. If light didn’t exist, c would still be c.

But I doubt it would get published, sure, everyone loves sacred Cow Hamburger, until it’s your Bull, er I mean Cow

I think you’re obsessed with trying to find a way around C so you’ve created overly elaborate experiments. But the fact is, if you think you have a workable experiment then do it and let the results speak for themselves. History proves that science LOVES to be proven wrong - it’s where the major discoveries lie and advances our knowledge. But you have to prove your hypothesis with math and experimentation, none of which you’ve demonstrated thus far.

Consider the galaxies at the far end of what we can see in the universe. Those galaxies are moving away from us at close to the speed of light due to expansion of the universe. The light that hits us from those galaxies is still measured at C. The difference is that the light is “red shifted” - the light from those galaxies is so far shifted that the light is no longer in the visible spectrum, it’s in the radio spectrum. If something was approaching us close to the speed of light the light would be blue shifted, but still coming at us at C.

I think this is where you get confused - I think what you would see would be light shifted from red to blue, not speed differences.

I am sure I would too, I’m way too ADD to do any good at learning in such a structured way, I would not be paying attention to what I am meant to and thinking my own thoughts or reading ahead, or behind instead.

The more degrees someone has the less likely they are to patent anything, and the fewer the more they will have, in a study at IMB if I recall the person with the most patents had no university education.

Oh and neither did Einstein which is probably why he had such a unique and creative idea, more-so being flawed but fooling most everyone.

I think that there is something about learning something yourself .vs being told something and having to repeat it back on a test even if you don’t agree that kills the ability to discover, to think independently and creatively compared to the autodidactic learner.

So it seems to me that is SR is to be found to be wrong, it will not be someone who has been educated to conform.

But hey, I’m sure you meant that if the you guy you knew that flunked out then I must be wrong about this? Because that is a far superior argument right?
Because we both like thinking and he flunked out, therefore I must be wrong. Rock Solid!
Everyone can now ignore all my points above with no further thought!

BTW that was sarcasm.

Sorry, no offence intended, unless you did in which case we are even

mythoughts, here is what you need to do. Abandon thought experiements; they are for weenies. Perform the experiment you describe, meticulously record the results after multiple trials, and report your methodology, experimental design, and results so that others can attempt to replicate your work.

100% certain.

If I am wrong, I do not think I will find the error myself.

It is also considered to be the speed of neutrinos.
Or the speed limit of the universe.

It could also be called the fastest we have yet measured light to travel in a vacuum under normal conditions, or at least the fastest result we choose to acknowledge.

Guess we found the new einstein

Simpler experiment.

A rocket ship travels between point A and point B at 50% of the speed of light.

Exactly halfway there, it turns on headlights and tail-lights. Does the light from the headlights, with the boost from the spaceship already traveling at a high % of c, hit the detector ahead sooner than the light from the tail-lights hits the detector behind?

Does light emitted from a traveling object travel faster in the direction of travel and slower in the opposite direction?

If light always travels at the same speed, regardless of how fast it was going when it was emitted, what does that mean?

We know that all experiments we can do show that light travels at the same speed coming or going. And for that result to occur–the invariance of the speed of light–other constants have to bend and stretch.

Einstein was a huge weeny then. He loved thought experiments.
As would hmm Hawking be.

I am sure there are more, Feynman I think, I think those 3 are very well known purely theoretical physicists.
Then there are those that do actual experiments and thought experiments too.
What about the Higgs Boson, that was a thought experiment (well, theory) that took ages to confirm.

Then you have Superstrings that are untestable, I have heard it said that quarks are unfalsifiable, though experiments have been done but the theory came first.

Additionally if the experiment was to be performed (it would require a budget and expertise I do not have, in fact I would need help establishing what SR would predict with respect to time dilation and the like to even know how fast, how long things would need to be with time pieces that are probably not available to me anyway.

Though the experiment seems very doable, though I doubt I am up to it.
And even if I was, with my resources and very limited engineering skill I suspect it would not even be considered done in a back yard inventor style.

I have seen DIY attempts to propagate signals faster than light, and they worked.
This was I think one of the submissions to the Tesla Symposium back in the 90’s.
He did fine work, but without the credentials and doing something considered impossible, guess where that went?

The only way back yard types have of getting the world to listen today is pretty much going to be like the Wright brothers at Kitty Hawk.
And you know the sceptics didn’t stop refuting them after the first flight either!

For something that can’t be shoved in peoples faces or accepted by academia or possibly replicated by lots of vaguely interested amateurs easily and cheaply, such an experiment tested by me would achieve probably precisely squat.

BTW, I do perform experiments. But this one is going to remain for me a thought experiment, at least this side of coming into a lot of money and a well equipped Lab and a bunch of scientists under my direction.

Sceptics are by default defenders of the trailing edge and will always oppose the leading edge of science and technology.
Be one if you want, but they always look very stupid and small minded with enough hind sight.