Absolute Time Clock Experiments: Einstein's Special Relativity

In summary, this experiment suggests that the time it takes for a light beam to travel from top to bottom mirror or from bottom to top mirror in a train, when looked at from inside the train is the same – doesn't matter if train is moving or not. However, if one adds one more condition that changing the color of light beam and bouncing it back is a faster process than sending a signal over the wires of the apparatus towards the counter, then the results should be different when the train is moving relative to the dock.
  • #141
Here is a common 'Crackpot', or even let it be - A Crackpot Term - that I want to try and understand:

'Non-direct' (proof of time dilation): A proof that presumably can not be gathered from within the relative moving frame.

Right? Wrong? Why should there be any difference between direct and non-direct experimental proof?
 
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  • #142
roineust said:
Here is a common 'crackpot', or even let it be - A crackpot term -, I want to try and understand:

Non-direct (proof of time dilation): A proof that presumably can not be gathered from within the relative moving frame.

Right? Wrong? why should there be any difference between direct and non-direct experimental proof?
Keep in mind that virtually all scientists prior to Einstein believed that the Earth was constantly moving through the ether in different directions and at different speeds at different times of the day and year, although they didn't know how fast or in which direction--that is what they were trying to measure. In essence, they believed that MMX was moving in the fixed frame of the ether. They weren't thinking in terms of relativity where you can consider yourself at rest within your own frame.

So I don't understand your distinction between direct and non-direct experimental proof in terms of what I'm trying to help you understand. You need to focus on the animations and tell me if you understand how they are illustrating what the scientists of the time believed.

With that in mind, I need you to respond to my questions:
ghwellsjr said:
...Does that help?

You first stated, "I can not understand well enough how it shows length contraction." Do you not see that the shape of the brown mirror is not a circle but is an ellipse and it is contracted in the direciton of Rover's motion?

...
You have a concern that there is no experiment to test length contraction like there is to test time dilation and yet you almost answer your own concern when you say they "nullify each other". Now if that is true, then how could time dilation be present unless length contraction is also present? I say "you almost answer your own concern" because have you considered that fact that time dilation means time is stretching out while the length is getting smaller? Don't you want both the time dilation and the length contraction to be getting larger by the same amount in order for them to "nullify each other"?
...
Crackpots are people who don't listen to other people who are trying to help them but tenaciously keep harping on an idea that they think is valid in spite of their being the only one to hold that idea. Of course, crackpots think their own pot is intact while everyone else's pot is cracked. This forum is dedicated to helping people who don't understand relativity. Other viewpoints are not tolerated. There are other forums for that.
 
  • #143
Hey ghwellsjr,

As I wrote - I got to this animation step by step, and I did notice, that you had in a previous post an index for the types of lines (colors and forms) - but still if I recall correctly, there is no explanation for the yellow line, and what more is, if the visually new contracted form, a result of different types of lines merging together, then it is not clear enough which ones...If there is an explanation for the yellow line, and I missed it, then pardon me and I will go over all the stages again.

Oh yes, tolerance...well, I might be just 'another one' or I might be 'the one!', but only when SR will not seem to me like a sort of unexplained magic, only then will I stop investigating this issue. What is the risk? Being out here? Well, I can take it...
 
  • #144
roineust said:
Hey ghwellsjr,

As I wrote - I got to this animation step by step, and I did notice, that you had in a previous post an index for the types of lines (colors and forms) - but still if I recall correctly, there is no explanation for the yellow line, and what more is, if the visually new contracted form, a result of different types of lines merging together, then it is not clear enough which ones...If there is an explanation for the yellow line, and I missed it, then pardon me and I will go over all the stages again.

Oh yes, tolerance...well, I might be just 'another one' or I might be 'the one!', but only when SR will not seem to me like a sort of unexplained magic, only then will I stop investigating this issue. What is the risk? Being out here? Well, I can take it...

I don't think you understand; you should read the rules you agreed to when you signed on the dotted line as it were. OH, and by, "The One"... you mean?...?
 
  • #145
roineust said:
Hey ghwellsjr,

As I wrote - I got to this animation step by step, and I did notice, that you had in a previous post an index for the types of lines (colors and forms) - but still if I recall correctly, there is no explanation for the yellow line, and what more is, if the visually new contracted form, a result of different types of lines merging together, then it is not clear enough which ones...If there is an explanation for the yellow line, and I missed it, then pardon me and I will go over all the stages again.

Oh yes, tolerance...well, I might be just 'another one' or I might be 'the one!', but only when SR will not seem to me like a sort of unexplained magic, only then will I stop investigating this issue. What is the risk? Being out here? Well, I can take it...
I'm partially color-blind and I intended to make mirrors in my animations brown and they look brown to me but I guess they look yellow to normally-sighted people. So the mirrors are yellow, not brown.

With that added bit of information, can you now answer my questions?

My goal is to bring you to the point where SR not only doesn't seem "like a sort of unexplained magic", but it will make perfect sense to you and you will be able to teach it to others.
 
  • #146
roineust said:
the fact that most of the experiments that prove time dilation are non-direct experiments
I have been away for a while, and I didn't really follow your manifesto, but this statement caught my eye. I don't know what you mean by "non-direct" experiments. All there is are experiments whose results agree with or disagree with the prediction of a theory (to within experimental error). So far all of them agree with SR and some of them disagree with Newtonian mechanics.
 
  • #147
hey ghwellsjr,

As much as I understand, one perspective of the dotted line (the mirrors around the moving guy) in SR-10 becomes a yellow/brown line in SR-11, if there is a reason for that change, then I don't understand that reason.

Besides that, as I said before, I still don't understand how to look at SR-11 in way that I will see the contracted form. Is it a combination of different kind of lines that I should look for?
 
  • #148
roineust said:
hey ghwellsjr,

As much as I understand, one perspective of the dotted line (the mirrors around the moving guy) in SR-10 becomes a yellow/brown line in SR-11, if there is a reason for that change, then I don't understand that reason.

Besides that, as I said before, I still don't understand how to look at SR-11 in way that I will see the contracted form. Is it a combination of different kind of lines that I should look for?
Do you understand that the goal here is to figure out where an observer must put his mirrors such that when he sets off a flash of light it will expand in a circle, relative to the ether, but then reflect off the mirrors in such a way that they create a contracting circle of light that eventually collapses on the observer in his final location?

To this end, do you understand that the dashed line in #9 shows the point of intersection of those two circles (one expanding and one contracting) and where we could put some mirrors if we wanted them to be relative to the ether?

And then #10 shows, in addition, where we could put the mirrors if we wanted them to be relative to the observer, in other words, moving with the observer so that he would see them as stationary with respect to himself. So we haven't actually put mirrors in #10, we merely trying to learn where to put the mirrors.

And finally in #11, we actually put a solid mirror moving with the observer in the place where the moving dashed line from #10 showed us to put it. Now, because the mirror is solid, the expanding blue circle gets reflected by the mirror (and so quits being a complete circle) and in the process, it creates the contracting red circle, but not all at once, it does it in pieces as you see the points of reflection sweeping across the mirror from left to right. Does this answer your question about the reason for the change from #10 to #11?

You last question is where to look in #11 for the contracted form. It's the overall shape of the mirror. Instead of being a perfectly round circle like the mirror is for Homer in #3, it is oval shaped. It isn't as wide as it is high. Can you see that? Compare #3 and #11 if you have trouble telling the difference.

If any of this doesn't make complete sense to you, then please ask more questions.
 
  • #149
ghwellsjr,

Ok,
It seems you added quite detailed clarifications here,
So, it will take me some time now, to get familiar with the new post.
 
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  • #150
Hey Dalespam,

Please explain to me which experiment confirmed length contraction.

Regarding time dilation being proved, what minority people like me call - 'non-directly',
please try to give me another example from physics, be it any kind of Pre-SR physics, in which, in certain conditions, it is not possible to measure something, no matter what you do, and that there is a theory that backs it up, as completely legitimate.

Thanks,
Roi.
 
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  • #151
roineust said:
please try to give me another example from physics, be it any kind of Pre-SR physics, in which, in certain conditions, it is not possible to measure something, no matter what you do, and that there is a theory that backs it up, as completely legitimate.
You are correct in principle. Such a theory would be unfalsifiable and therefore non-scientific. SR is definitely falsifiable as there are many ways to measure its experimental predictions, so this comment certainly doesn't apply to SR.
 
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  • #152
Roineust, I think it is important to understand that every law, every postulate in science has a certain scope of application, SR is no exception. You are asking of it something it was not meant to solve, Einstein himself repeatedly said that all SR had to say about the ether is that it was an unnecesary (superfluous) assumption in the range where SR applies, which is an idealized space (minkowskian) where masses can be neglected and all frames are inertial in the Newtonian sense (uniform velocity). This is obviouly a mathematical idealization that is not our real universe but that happens to work very well for problems where one doesn't have to take into account gravitation , which are quite a lot (all EM applications,weak force, etc ...) because the gravitational interaction is very small to be detected by our experiments , like in the particle accelerator experiments you cite (it is within experimental error bars).
If you want to take those gravitational effects into account you have to turn to GR, there you will find that in practical terms an ether is used (even though you can't use the taboo word ether, it is frowned upon due to historical connotations). An absolute rest frame is considered for a certain set of "fundamental observers". This absolute rest frame is realized for instance in the form of the CMB that fills the vacuum. Of course you'll be told that it is not a "real" absolute rest frame but in practical terms is used as if it were because otherwise we can't concoct a coherent cosmic time line, or in other words the absolute clock you seek is been around for decades, is the one that counts the time from the BB to now.
 
  • #153
If what you say is correct,
For me at least, it is a big surprise!

So now, if indeed so, I might have a whole new set of questions.

But first I want to be sure that the device I am asking about (Please look at the 'Michelson–Morley experiment?' thread), will indeed function, as an absolute clock or let it be an 'absolute clock' (This is still not clear as well).

But, I don't think that this is the situation - that is, I am trying to understand, the reason to what seems to be the common consent - that neither an 'absolute clock' nor an absolute clock is possible.Roi.
 
  • #154
TrickyDicky said:
If you want to take those gravitational effects into account you have to turn to GR, there you will find that in practical terms an ether is used (even though you can't use the taboo word ether, it is frowned upon due to historical connotations).
It is not just a matter of historical connotation. The metric of GR has nothing to do conceptually with the luminiferous aether of the early 20th century. They are simply unrelated concepts and to use the same label is deceptive. The defining property of the aether was velocity, a property which the metric does not have, and the defining property of the metric is curvature, a property which the aether did not have. It is not simply a matter of social custom and taboo, the concepts themselves are too different to be identified with one another.

Think of all of the problems that have arisen in QM due to their continued use of the word "particle" to describe a quantum concept which is very different from the classical notion of a particle. Calling the metric "aether" would lead to similar confusion.
 
  • #155
DaleSpam said:
It is not just a matter of historical connotation. The metric of GR has nothing to do conceptually with the luminiferous aether of the early 20th century. They are simply unrelated concepts and to use the same label is deceptive. The defining property of the aether was velocity, a property which the metric does not have, and the defining property of the metric is curvature, a property which the aether did not have. It is not simply a matter of social custom and taboo, the concepts themselves are too different to be identified with one another.

Well, let's not call it ether if it can be confusing, I certainly wasn't talking about the "luminiferous ether" pre-Einstein, but to the ether referred by Einstein in many occasions in relation with GR like his "Ether and the Theory of Relativity" from may 1920.
Let's call it an absolute rest frame that is implicit in the GR equations when solved with any metric and coordinates. You just have to realize that GR is not Lorentz invariant when applied to any realistic cosmological object (with mass).


DaleSpam said:
Think of all of the problems that have arisen in QM due to their continued use of the word "particle" to describe a quantum concept which is very different from the classical notion of a particle.
Totally agree. I actually think the word "particle" has been more of a problem in QM, than the word "ether" in GR.
 
  • #156
DaleSpam said:
It is not just a matter of historical connotation. The metric of GR has nothing to do conceptually with the luminiferous aether of the early 20th century. They are simply unrelated concepts and to use the same label is deceptive. The defining property of the aether was velocity, a property which the metric does not have, and the defining property of the metric is curvature, a property which the aether did not have. It is not simply a matter of social custom and taboo, the concepts themselves are too different to be identified with one another.

Think of all of the problems that have arisen in QM due to their continued use of the word "particle" to describe a quantum concept which is very different from the classical notion of a particle. Calling the metric "aether" would lead to similar confusion.

Probably you meant the luminiferous aether of the 19th century. The defining property of the Lorentz ether is that its velocity cannot be used as reference for a metric. Therefore, Einstein stated that the ether of GRT is based on the Lorentz ether. Its main difference is that its properties are affected by matter, which is a feature that Lorentz's pre-GRT ether lacked.
But I agree with your comment about the confusing use of the word "particle" in QM, and certainly the metric ("the map") should not be confused with the physical model ("the territory") that one may invent to make sense of the metric.

Harald
 
  • #157
harrylin said:
The defining property of the Lorentz ether is that its velocity cannot be used as reference for a metric.
The Lorentz aether was still attributed a velocity, it is just that it also had other ad-hoc properties (caused length contraction in moving rods) that conspired to make the velocity unmeasurable.
 
  • #158
OK,
This is not the first time I am asking this question.
But in my opinion , I did not get a clear enough answer to that question.

If there are people, who think that, they already gave me the full answer, and that I am just repeating myself - Please! I am really sorry! excuse me, and just ignore this message. In that case, please spare me the berate.Here is a diagram.
It takes into consideration time dilation (clock C), the constancy of the one way of the speed of light in inertial frames, and a slow transport synchronization of the clocks A and B, synchronized once in the inertial stationary frame, and once in the inertial moving frame (second sync, only after the moving frame becomes inertial).

The diagram depicts, what is considered **not a true** scenario: clock A and clock B , in the moving frame, do not turn on together (the blue and white circles).

My question is, why is this scenario wrong? What is it that causes the true scenario to be, that both detectors in the moving frame turn on together? e.g. both circles in the moving frame should be blue as well.

Thanks,
Roi.
 

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  • #159
DaleSpam said:
The Lorentz aether was still attributed a velocity, it is just that it also had other ad-hoc properties (caused length contraction in moving rods) that conspired to make the velocity unmeasurable.

No matter what model of nature one likes to use with SR, it has to obey the PoR.
 
  • #160
roineust said:
OK,
This is not the first time I am asking this question.
But in my opinion , I did not get a clear enough answer to that question.
[..]
The diagram depicts, what is considered **not a true** scenario: clock A and clock B , in the moving frame, do not turn on together (the blue and white circles).

My question is, why is this scenario wrong? What is it that causes the true scenario to be, that both detectors in the moving frame turn on together? e.g. both circles in the moving frame should be blue as well.

Thanks,
Roi.

What you perhaps did not understand:

Assume that a system (a real platform) has two similar clocks are side by side, in rest on that platform. Its two clocks are synchronized with each other.
Now the clocks are separated with identical motors that push them an equal distance in opposite directions. According to an observer on the platform who considers himself in rest, the clocks must still be in tune with each other.

However, according to you, that platform is moving fast to the left.

According to your measurements, the clocks on that platform are ticking slower due to the fact that they move along with that platform. Now, when a clock is transported to the left, it will move faster than the platform. And when a clock is transported to the right, it will move slower than the platform.
Therefore, according to your measurements, the clock that is transported to the left will be ticking slower, during that transport, than the clock that is transported to the right.
That exactly compensates for the difference in time delays of the light rays that you expect.
 
  • #161
But what I understood was, that the whole point in the slow transport technique, is that by moving the synchronized clocks apart slow enough, this movement does not need to be included, in any calculation of the scenario...
 
  • #162
roineust said:
But what I understood was, that the whole point in the slow transport technique, is that by moving the synchronized clocks apart slow enough, this movement does not need to be included, in any calculation of the scenario...

Slow transport is only slow relative to the platform on which the clocks are transported. Clocks that are slowly moved over a not too far distance will remain approximately synchronized with other clocks in that system - according to the platform's synchronization with light rays!

Didn't you understand Einstein's train example? Distant clocks along the direction of motion that are synchronous according to the moving platform, cannot be also synchronous for the rest platform.

As I formulated it, the transport may be fast: both clocks will always remain exactly synchronized with each other for the moving platform. For your example it doesn't matter if they are both behind, as long as they are equally behind.

Thus, and I repeat:
According to your measurements on a stationary platform of the moving platform, the clock that is transported to the left will be ticking slower, during that transport, than the clock that is transported to the right.
That exactly compensates for the difference in time delays of the light rays that you expect.
 
  • #163
What I don't understand is the relation between experiment and PoR:

For proving that there is time dilation in clock C, you have got to have another clock in the stationary frame, in order to measure this time dilation.

But, what need is there for measurement outside the moving frame, relating to what happens between clocks A and B. This synchronization process is done only between clocks A and B, so where and how arises experimentally the act of measuring from outside the moving frame, what happens between clock A and B?
 
  • #164
roineust said:
What I don't understand is the relation between experiment and PoR:

For proving that there is time dilation in clock C, you have got to have another clock in the stationary frame, in order to measure this time dilation.

But, what need is there for measurement outside the moving frame, relating to what happens between clocks A and B. This synchronization process is done only between clocks A and B, so where and how arises experimentally the act of measuring from outside the moving frame, what happens between clock A and B?

I don't understand your question. Did you understand my answers?

The relation between experiment and PoR is that both systems measure what you drew at the top; any inertial platform may be pretended to be "in rest".
 
  • #165
roineust said:
Here is a diagram.
It takes into consideration time dilation (clock C), the constancy of the one way of the speed of light in inertial frames, and a slow transport synchronization of the clocks A and B, synchronized once in the inertial stationary frame, and once in the inertial moving frame (second sync, only after the moving frame becomes inertial).

The diagram depicts, what is considered **not a true** scenario: clock A and clock B , in the moving frame, do not turn on together (the blue and white circles).

My question is, why is this scenario wrong? What is it that causes the true scenario to be, that both detectors in the moving frame turn on together? e.g. both circles in the moving frame should be blue as well.
Is there an experiment that was done in the past, that can be considered equivalent, as a whole, to this device, and that is possible to indicate within that experiment, the exact equivalent elements, not only of C clock, but also of both A and B clocks?

Thanks,
Roi.
 

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  • #167
How come experiments could not resolve, to total agreement, the question of the constancy of the one way speed of light? How could slow transport, influence that question anyway? Say someone thinks that slow transport actually does influence the clocks - So then he should take into consideration slow transport - how does that make the results of experiments show that the one way of the speed of light is not constant? Is the claim of these theories, that it depends on the specificities of the scenario? How? Weren't experiments made testing different scenarios?
 
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  • #168
roineust said:
How come experiments could not resolve, to total agreement, the question of the constancy of the one way speed of light? How could slow transport, influence that question anyway? Say someone thinks that slow transport actually does influence the clocks - So then he should take into consideration slow transport - how does that make the results of experiments show that the one way of the speed of light is not constant? Is the claim of these theories, that it depends on the specificities of the scenario? How? Weren't experiments made testing different scenarios?

Again, I don't understand your questions as you claim the opposite of what I explained and which you did not comment or ask about. Running away from the answers on your questions only accumulates confusion on error...

I'll answer once more the same as before, contrary to what you claim:

The effect of fast and slow transport is exactly as the theory predicts as experiments confirm. For your example, fast transport is perfectly fine too. One should take into consideration the effect of clock transport to show that although the one way speed of light is constant, the relativity principle still works. The scenario doesn't matter, that's the whole point.

Good luck,
Harald

PS Did you perhaps not understand that the constancy of the speed of light and the relativity principle are in apparent contradiction? That's how the development of relativity theory started.
 
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  • #169
roineust said:
How come experiments could not resolve, to total agreement, the question of the constancy of the one way speed of light?
Because that is a matter of definition, not experiment. Specifically, the one-way speed of light is completely determined by your (arbitrary) choice of synchronization convention. The Einstein synchronization convention defines simultaneity in an inertial reference frame, but other conventions are possible.
 
  • #170
I began my whole journey, regarding SR, from a statement that says, that it is not possible to determine a relative inertial change, from within the ship, without looking out of the ship's window (which stands for several possibilities of observation and communication with the outside world) or without feeling the acceleration that led to this inertial change (which stands for several possibilities for detecting acceleration).

Now: Is this statement also a matter of definition? Can you give me a simple example for how such a statement, which is a statement that can be understood to a very high intuitive degree, can be defined in several ways, and not just in one way? Is that statement a matter of convention as well?
 
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  • #171
roineust said:
Is this statement also a matter of definition?
No. See sections 3.5 and 3.6 of the above reference.
 
  • #172
OK,
So how come experiment results, such as in sections 3.5, 3.6, that are not a matter of convention, but agreed upon according to all conventions, results in multiple conventions? Aren't such experiments, considered some sort of fundamental physical basis, that only on it, is it possible to build a mathematical definition? Isn't there in physics, some fundamental group of experiments, that are considered singularly truth, without regards to convention - and only on this group of experiments, the mathematical definitions are built?
 
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  • #173
roineust said:
So how come experiment results, such as in sections 3.5, 3.6, that are not a matter of convention, but agreed upon according to all conventions, results in multiple conventions?
What?

roineust said:
Aren't such experiments, considered some sort of fundamental physical basis, that only on it, is it possible to build a mathematical definition? Isn't there in physics, some fundamental group of experiments, that are considered singularly truth, without regards to convention - and only on this group of experiments, the mathematical definitions are built?
Defined quantities are not restricted to things which are experimentally measurable. For example, a potential is not measurable due to the possibility of gauge transformations, but it can easily be defined.
 
  • #174
This still doesn't explain the relation between, the one way speed of light, slow transport and an experimental action.

Say we have the usual two frames, one called "moving" the other called "stationary".

The moving frame, is a jet flying a device. The Stationary is the on-ground station with the same device. This device has two clock-light-detectors. These two identical devices' two clocks each, are both separated by a slow transport mechanism, only after their frames are fully inertial relatively to one another.

One theory will claim that, because of the affect of slow transport mechanism of separating the clocks, no matter how slow, the on-ground clock will measure the speed of light as X and the jet device measures the speed of light differently, say as Y.

The other theory will claim that the slow transport mechanism, doesn't change the measurements results in comparison between the two frames, exactly because the separation of the two clocks, is done slowly, and that both on-ground and jet devices, will measure the speed of light to be the same, let it be X and X or Y and Y or Z and Z.

Now, here you probably, already know what I don't understand. Putting such a device on a jet is very feasible- and the experimental result can be true to only one of the theory types above ,and not to both.

So how come conventions or definitions, change measurements in this case, of having only one true answer, regarding the constancy of the one way speed of light?
 
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  • #175
Roi,

Any "theory" that predicts that an experiment performed on an inertially "moving" platform (like a jet) will get any different result than when performed on an inertially "stationary" platform (like the earth) will be an invalid theory and will be discarded because it does not comport with reality.

Every experiment performed on any inertial platform (one that is not accelerating) will appear exactly the same as if it were performed at rest with respect to an absolute ether rest frame. The one way speed of light will appear to be the same in all directions, no matter how you attempt to measure it. The round-trip speed of light will appear to be a constant in all directions, no matter how you attempt to measure it. There will be no detectable ether wind, no matter how you attempt to measure it. All identical distant clocks at rest in this frame can be synchronized by many different methods and all appear to run at the same speed. All identical rulers at rest in this frame will appear to be the same length no matter their orientation or location. There is no experiment that you can perform on any inertial platform that will behave any differently than it would on any other inertial platform. These characteristics have nothing to do with any theory, or any convention, or any definition; they are just the way nature works.

Do you question any of these facts? Do you have any doubt about the truthfullness of any of these statements?
 

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