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Quote from: hamdani yusuf on 14/03/2021 12:39:28https://www.researchgate.net/project/Tests-of-the-One-way-Speed-of-Light-Relative-to-a-Moving-ObserverQuote... the speed of light between fixed points on the surface of the Earth is not the same in all directions; light travels faster west than east! GPS engineers try to mask this fact by assuming light speed c and making the so-called "Sagnac Correction".Has anyone worked with GPS to confirm or refute the claim?West does not define a unique direction, since west for me is the exact opposite direction as west in Beijing. This is because their 'fixed points' are fixed only in a rotating frame of reference, and yes, in such a frame, light travels faster west than east, exactly as mandated by SR. SR could be falsified immediately if the Sagnac effect didn't work. In a light tube going around the Earth, light has less distance to move in the west direction than in the east direction, so of course the westbound light gets to the moving source/detect faster than the eastbound. The Sagnac effect relies on that fact to detect absolute rotation.
https://www.researchgate.net/project/Tests-of-the-One-way-Speed-of-Light-Relative-to-a-Moving-ObserverQuote... the speed of light between fixed points on the surface of the Earth is not the same in all directions; light travels faster west than east! GPS engineers try to mask this fact by assuming light speed c and making the so-called "Sagnac Correction".Has anyone worked with GPS to confirm or refute the claim?
... the speed of light between fixed points on the surface of the Earth is not the same in all directions; light travels faster west than east! GPS engineers try to mask this fact by assuming light speed c and making the so-called "Sagnac Correction".
Quote from: Hal on 17/03/2021 11:32:22If I detect difference in propagation times of light in opposite directions between two points in a closed lab on Earth, this is nothing other than detection of absolute motion (remember Galileo’s ship thought experiment). But you don't.
If I detect difference in propagation times of light in opposite directions between two points in a closed lab on Earth, this is nothing other than detection of absolute motion (remember Galileo’s ship thought experiment).
Quote from: Hal on 16/03/2021 05:14:57 If special relativity predicts that the time delay of light is different in the two directions in the first experiment, what is the prediction of special relativity ( SRT) in the second experiment?Special relativity predicts that the time delay of light is the same in the two directions in the first experiment.Quote from: Halc on 16/03/2021 03:42:03That's easy. Relative to that inertial frame, light takes the same time to go in either direction since the two mailboxes are both stationary. That's one case. There was another one?
If special relativity predicts that the time delay of light is different in the two directions in the first experiment, what is the prediction of special relativity ( SRT) in the second experiment?
That's easy. Relative to that inertial frame, light takes the same time to go in either direction since the two mailboxes are both stationary. That's one case. There was another one?
If you know the red shift then you also know how hot it isYou also know how bright it "looks" and from that you can work out the relationship between its size and its distance.Then you can look at spctral braodening and deduce how fast some bits are moving compared to other. That gives information on teh rotation rate.You can combine that data with the understanding we have of how stars work and get a good idea about the other characteristics- notably size.But what's interesting is that you didn't realise they could do that, yet you are prepared to make up stuff like thisQuote from: puppypower on 16/03/2021 18:53:23The solution is we will try to use space and time; photons, to simulate and estimate the mass. This is two variables; 2-D, used to model 3-D. This is nobody's fault, but it is what we have to deal with.Why not study science?
The solution is we will try to use space and time; photons, to simulate and estimate the mass. This is two variables; 2-D, used to model 3-D. This is nobody's fault, but it is what we have to deal with.
am I supposed to take your word for it?
I proposed a GR red shift effect, that should stem from the black hole in the center of our galaxy.
It is so much easier being a critic.
Why not study science?
I think special relativity predicts it.
It only assumes constant speed of light relative to an inertial frame in flat Minkowskian spacetime, and a rotating frame (nor a straight shot between say Earth and Mars, spinning or not) meets this qualification.
QuoteBut then a self contradiction of special relativity follows....but this leads to a self contradiction of special relativity.Another repeat. You've not been able to demonstrate this supposed self contradiction mostly due to lack of any precise description of any hypothetical experiment.
But then a self contradiction of special relativity follows....but this leads to a self contradiction of special relativity.
Imagine an observer and two light sources in a closed lab at the equator. One point is to the East of the observer and the other point is to the West, with the observer at mid point between the two sources.In the Earth centered rotating frame, the propagation times of light in the two directions (from the two sources) is different, according to special relativity. This is supported by experiments, such as the GPS Sagnac effect.But this leads to a contradiction. If an observer in a closed room (lab) detects anisotropy of the speed of light, this can only be due to acceleration, or due to absolute motion
Therefore, special relativity predicts the Sagnac effect in the Earth centered rotating frame but this in turn leads to violation of the principle of relativity.
There is yet another self -contradiction of special relativity. Consider the observer and the light sources again. This time we analyze the problem relative to the lab frame, not relative to Earth centered frames.
Consider two reference frames, S and S'. The observer is at the origin of both frames. S is the (almost) inertial lab frame and S' is the rotating lab frame.
We should be able to use our lab frame because it is almost inertial. If you insist that only the ECI frame should be used, this would violate the principle of relativity.
Rotation of the lab frame (S' ) will not affect the speed of light
since we have assumed that the observer is at the origin of the lab frame.
My argument is that a rotating frame will not affect the speed of light between two points if one of the points is at the origin of the rotating frame.
To avoid clock synchronization problems, if any, we can use light interference experiments. But we can also synchronize clocks from knowledge of our absolute velocity. ( the Silver tooth experiment)
Moreover, we can make S and S' as inertial as possible by assuming enormously increased radius of the Earth, and the angular velocity decreased by the same factor, to keep the tangential velocity the same.
QuoteRotation of the lab frame (S' ) will not affect the speed of lightNonsense. Light speed is completely variable relative to a rotating frame. It can even be negative or any arbitrarily high speed.QuoteMy argument is that a rotating frame will not affect the speed of light between two points if one of the points is at the origin of the rotating frame.Even if the observer is at the origin, this is false. Simple geometry will say otherwise. Not even Newton would agree with your assertion.
You still haven't made any mention of how exactly these guys in the windowless lab have gone about performing their experiment. It's not like a baseball where you can point a radar gun at something to get its speed. I don't think they have GPS satellites in there with them. The only clue you've given is that they're taking their measurements relative to a rotating frame of reference.
But it is absolute motion. Rotation is absolute, and they're taking their measurements relative to that rotating frame and measuring exactly what the theory predicts,
I was actually saying that a rotating frame will not affect the speed propagation time of light between two points if one of the points is at the origin.
They take measurements relative to the rotating lab frame with the observer/detector at the origin.
Even clock synchronization is not a problem here, because the center of the rotating frame is (almost) inertial.
The experiment cannot physically measure / sense rotation (ω), it can only measure ωR which is linear velocity.
Suppose that at first the observer in the closed lab knows that he/she is moving in a circular path around a center, and knows his R and ω.
Then the radius of the circle was increased and ω decreased by the same factor, without the observer's knowledge
There is no way the observer can tell their new angular velocity by using this experiment.
If this experiment cannot measure ω,
the observed anisotropy in the speed of light
I have to disagree. The time between two events (points in spacetime) is completely frame dependent, and thus the choice of frame, rotating or otherwise affects the propagation time of light between them, by definition. Quote from: Hal on 20/03/2021 20:14:32They take measurements relative to the rotating lab frame with the observer/detector at the origin.There is only one observer detector? What’s at the other end of the lab then? Again, we have a lab at the center of the Earth? The south pole perhaps at least? There’s no sending a signal east or west from there you know. Quote from: Hal on 20/03/2021 21:34:08The experiment cannot physically measure / sense rotation (ω), it can only measure ωR which is linear velocity.If the observer is held stationary in the rotating frame, it is trivial to physically measure proper rotation (ω) which is absolute. QuoteThen the radius of the circle was increased and ω decreased by the same factor, without the observer's knowledgeThey can measure that, so they’d know.QuoteThere is no way the observer can tell their new angular velocity by using this experiment.You haven’t described an experiment. They could tell if they chose to measure their angular velocity and radius.QuoteIf this experiment cannot measure ω,I can run a tape measure over the length of my computer screen here and measure its size. That experiment cannot measure ω. The failure of that experiment to measure ω does not imply that ω cannot be measured.
Classically, the time of propagation between two points in a lab on the surface of the Earth is constant independent of lab rotation if one of the points is at the origin of the lab inertial frame.
There is no lab at the center of the Earth. The lab is on the surface of the Earth. We are only analyzing the experiment in the ECI frame and then in the inertial lab frame.
I was saying that the observer cannot know the ω of his lab by this experiment which only measures the time difference between the light pulses.
If rotation was the fundamental cause of the effect observed, the observer would know his ω from this experiment alone.
Trivially, a physicist would not conclude that rotation is the fundamental cause of the effect observed just because he can measure rotation by other means.
He may as well hypothesize that temperature is the cause because he can measure the temperature.
Quote from: Hal on 21/03/2021 17:56:35Classically, the time of propagation between two points in a lab on the surface of the Earth is constant independent of lab rotation if one of the points is at the origin of the lab inertial frame.That wasn't even true in 19th century classic physics. Endlessly repeating this statement doesn't make it less wrong.