RelativityCobblers

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Nope, it’s supposed principles that can’t deal with even simple thought experiments which are useless!

I think the problems are entirely of your own creation. If you want to apply the principles of special relativity to your thought experiments, then you need to identify the space-time coordinates of the events you are trying to consider. Then, you apply the Lorentz transformations to convert between these space-time coordinates in one inertial frame and in another inertial frame. It is logically impossible for anything to go wrong in this process, since the Lorentz transformations are a mathematically well-defined set of transformations from one inertial coordinate system to another.

If you are not doing that, but instead using some equations that you "came up with," such as you talked about in your original posting, then you are not using the rules of special relativity. All you have have succeeded in doing is showing that your own dreamed-up rules don't work. That is not a surprise.

First of all, the speed of light is not a universal constant - it’s an invariant. The difference is crucial. Its numerical value is constant only within a given medium and in the absence of gravity, and it calculates directly from that medium’s permittivity and permeability.

Since all observers within that medium detect the same permittivity and permeability everywhere (otherwise they wouldn’t be in the same medium!), regardless of their states of relative motion, they all must share the exact same laws of electrodynamics. This is possible only if the geometry of the underlying spacetime is Minkowskian. It is not possible in a Euclidean space.

In other words, the situation is exactly the other way around as you put it in the sentence I quoted you on - you need Special relativity to avoid what would otherwise be some very uncomfortable paradoxes! That was the original reason why Einstein was looking for the theory of relativity in the first place: because empirically we can see that all observers experience the same laws of physics, and that couldn’t be reconciled with the laws of electrodynamics as they were formulated back then.



The model that describes photons - quantum electrodynamics - is a relativistic theory, like all quantum field theories. It wouldn’t work otherwise. The same is true for the entire Standard Model - neither you nor your computer nor any other bound matter in the universe could even exist without relativity, at least not in the form we empirically observe it right now.



Here is the heart of your problem - you assume that relativistic effects are something that “happens” to objects/observers, that they are somehow intrinsic to them. If that were so, the entire model would indeed be problematic. But that is not the case. What changes is neither the photon nor the emitter, but rather their mutual relationship in spacetime.

As an analogy(!), consider two people standing side by side. Now one of them (let’s call him A) walks off into the distance; as a result, he appears smaller to stationary person B. Does that mean that A has physically shrunk, and that B has somehow made him shrink across some vast distance? Of course not. A is still the same size in his own frame. What has changed, in terms of geometric optics, is merely the relationship between A and B. The effect is physically real, but is one of geometry, not physical shrinkage.

The same is true in relativity - the world lines of observers do not change (how could they? we remain in the same spacetime), they are just being looked at from a different angle. Quite literally actually, because at least for inertial motion, relative velocity can be expressed as a hyperbolic angle...

Your opinion means nothing. The speed of light is not being ‘held’ to anything — it is a universal invariant, discovered by humans and not created by them.

Guys, The problem is that you still have not addressed the question I put to you. If we take emitter A, the one which isn’t accelerated, as our static reference, then it is generally accepted that photon A will continue at a velocity of C. When emitter B is accelerated in the other direction, will this in any way affect the activity of photon B? I can think of no mechanism for this, so photons A & B should continue on side by side, and so the velocity of photon B relative to emitter A is also C. In the meantime, distance is increasing between emitters A & B, and though it should be slow enough so as not to invoke any Relativity effect, and will be tiny compared to the distance traveled by the photons, and quite unmeasurable in practical terms (in contrast to some fantastic claims made in an earlier post) it is nonetheless, within the terms of this thought experiment, very real! If Relativity is not invoked, then the time frame of both emitters remains the same, so in the same time, the distance between emitter B and photon B has increased, so by what magic can the relative velocity between them remain at C? This math is about as basic as it gets, so anyone who doesn’t get it can hardly lay claim to understanding anything as convoluted as Lorentz (how Fitzgerald must be crying in his grave) transformations!

It sounds as if you are using some non-relativistic formulae to do your calculations (for example, "If Relativity is not invoked..."), and then complaining that they give results that are incompatible with the constancy of the speed of light. Well, of course that will happen! You have to use the relativistic formulae in the calculation.

And the Lorentz transformations are not "convoluted." They are, by construction, the correct formulae for transforming between inertial frames of reference in such a way that the the speed of light is the same in all such frames. And they are constructed that way because it is experimentally observed in nature that the speed of light is the same in all inertial frames.

It is logically impossible to arrive at any of the contradictions of the kind you are claiming, if you just do the correct calculations using the correct formulae.

No. But what it does do is change the relationship between the photon and the emitter in spacetime. This is where the relativistic effects come from. In this specific scenario, due to the acceleration present in frame B, there will be a frequency shift measured in that frame.
The photon itself traces out a null geodesic in spacetime; since the geodesic structure of spacetime is diffeomorphism invariant, this is true for all observers, regardless of their state of motion, and regardless even of the exact geometry and topography of the spacetime in question. Thus, all observers must detect the photon to be moving at c. This is actually just common sense, because there is no such thing as a photon moving at anything other than c - if it were, then it wouldn’t be a photon anymore, so you could change the nature of a particle just by going into a difference reference frame, which is of course nonsense. Luckily, relativity prevents such paradoxes from occurring, by ensuring that the spacetime interval is invariant.

As a side note, if the observer’s frame is accelerated, then from his point of view the same region of spacetime will contain more than one photon, as compared to a non-accelerated reference observer. That’s called the Unruh effect.



A Lorentz transformation is a simple rotation about an angle in spacetime. That is about as elementary as it gets, and certainly not convoluted. Note that in your specific scenario neither frame B nor the photon are inertial frames, so they are not related by Lorentz transformations.



By the simple fact that, if a photon traces out a null geodesic in one frame (which it must, since it is massless), then it will necessarily trace out a null geodesic in all frames. So the magic is the symmetries of spacetime. Physically this simply means that a photon remains a photon, regardless of who looks at it. Without relativity, that would not be so, and you’d get some really awkward paradoxes.

This is just a variation on the quip made by stand up comic Stephen Wright: his question "if you were driving your car at the speed of light, and then....turned on your headlights - would your headlights DO anything?". Its a funny question because its based upon Newtonian physics, and leaves out relativity.

you're variation on the theme is to ask: "If you were driving your car at the speed of light - how would that effect your perception of the street lamps in front of you, your perception of the street lamps behind your car, and your perception of the dome light inside your own car, and that of the streetlamps out side your car rushing by abreast of your car?".

To honest I am not sure of the answer, but I think that the answer involves doppler. The light photons from all of the above sources would stll move at the same speed of light. But the street lamps in front of you would be blue shifted, those behind red shifted, those abreast, and inside your car would look their normal color.

However to the pedestrians on the street: Your headlight would be blue shifted as your car came at them, and your rear lights would be red shifted as you went pass them down the road.

The OP is using Newtonian thinking to support his anti-Relativistic arguments. He is not practicing science.

I'm not practicing science? Really? When first I read of the Michelson Morley experiment, many decades ago, about the first thing I did was set it out on a large piece of graph paper. Going with the idea that C was a universal constant (which might have had some credibility back then [*]) and doing the geometry, I found, as M and M expected, that the two pulses of light should not arrive on target in the same instant. Repeating this with the pulses leaving their emitters at C, and then factoring in the vectors of the emitters’ velocity relative to the “static” observer, and hey ho, the two pulses arrive at the same time, which, as you should know, is the result that M and M reported. Back then, light was still considered a wave, so this result might have seemed mysterious, but once Einstein had done his photovoltaic stuff, he should have realized the expectation was no longer valid. At this point he should have recalled the principle of Ockham’s razor (an honorary axiom, as far as I’m concerned) repeated my calculation, and realized that, with a very logical and simple explanation that addressed the results, there was no need to complicate things further; The M and M result proves that light speed is not a universal constant (and your habit of repeating this fatuous claim won’t alter the facts)!

Do feel free to do some science, yourselves, and check out the geometry yourself, and then try to recall that real science is based on evidence, not belief!

[*] Even when considering light to be a wave supported in a medium, it is still a bit dubious to assume it is a universal constant; sound waves in air, for instance, are constant for a given set of conditions, but are changed with any difference in temperature, so why was anyone so sure that the speed of light in the aether didn’t vary similarly?

Get over yourself. You're not impressing anyone.

Indeed, after almost 15 years, he should just let it go!

Unfortunately, it is a bit like trying to argue with a flat-earther, or a moon-landing denier; it is essentially hopeless to convince them of just how ludicrous their beliefs are.

In this case, the OP seems to have picked up a few smatterings of information, but has insufficient understanding to be able to grasp the whole picture.

As Alexander Pope said more than 300 years ago,

A little learning is a dangerous thing;
drink deep, or taste not the Pierian spring:
there shallow draughts intoxicate the brain,
and drinking largely sobers us again.

It's easier for them to believe in a random collection of contradictory myths than in a solitary self-evident truth.

I remember going through a similar exercise many years ago, and kept ending up with the same result. Then I gave up!

I’d like to propose an experiment (I may be repeating myself, but I can’t find the previous post, and I’ve got a new twist to add) which should sort out this dispute once and for all :

It’s to do with relativistic mass, so the first question is if relativistic mass is disproven, does that also disprove General Relativity Theory?

I believe it does, and have already pointed out that any charged particle in a field should, according to the principle of equivalence, behave like any other object subject to an accelerative force of some kind. That is to say that acceleration should be brisk, initially, because of the relative velocities of object and driving stream, and then ease off as the object approaches the velocity of the driving stream. It is the expectation that charged particles should have constant acceleration that is aberrational!

The experiment:

It should be very easy to drive some particles up to near light speed, and then divert them down a long tube in which the driving field has been reversed. The distance travelled by those particles will vary distinctly between a rest mass model, and one with relativistic mass, so why has nobody done this already? At the very least, no such experiment appears to have been published (which would be very strange, given how this is a possible Nobel prizewinner!).

The calculation for the rest mass model is straightforward, that for the RM model a bit more tedious, as it involves something like a compound interest calculation in reverse, but it shouldn’t be beyond any young physicist. In fact, that second calculation is superfluous, as it would be enough to make the tube something like twice the length of the first calculation, with a detector on rails at the far end.

The outcome could hardly be clearer: If particles are detected, then GRT is proven valid. If not, all that is then needed is to drive the detector up the tube until particles are detected. The likely outcome it that particles would be detected at the calculated distance for the rest mass model (anything else would be truly weird) disproving relativistic mass, and GRT would then, at the very least have to be considered flawed, meaning that most of physics over the last 60 years or so, would have to be re evaluated.

Any takers? Anybody find any flaw in my proposal (unlikely; I’m a serial inventor and my designs have always worked in the past)?

If any cyclotron directors are unwilling to fit this simple experiment into their schedules, then they really should be made to answer why!

Interesting question, cannot answer

Have worked with many scientists, each is as different as people are different.
Tough to lump into one universal bag.

But, trying to sort it out is a courageous endeavor