More tests for relativity

[DanMP]

I imagined few more tests for relativity. Please tell me if they were already performed and with what outcome.

 

The first one is about 2 atomic clocks, one at the South pole (to be at rest in Earth's center frame) and the other in Space, around the Sun, on Earth's orbit (same distance, same speed) but far from Earth. So, both clocks are travelling with huge, same speed around the Sun, but the one on Earth "tick" slower due to gravitational time dilation caused by the Earth. This is the only difference, or the clock on Earth benefits from linear frame dragging and is not afected by the Earth movement around the Sun? Did anyone perform this, or at least apply relativity to see the outcome?

[imatfaal]

I imagined few more tests for relativity. Please tell me if they were already performed and with what outcome.

 

The first one is about 2 atomic clocks, one at the South pole (to be at rest in Earth's center frame) and the other in Space, around the Sun, on Earth's orbit (same distance, same speed) but far from Earth. So, both clocks are travelling with huge, same speed around the Sun, but the one on Earth "tick" slower due to gravitational time dilation caused by the Earth. This is the only difference, or the clock on Earth benefits from linear frame dragging and is not afected by the Earth movement around the Sun? Did anyone perform this, or at least apply relativity to see the outcome?

 

 

Rotational frame dragging is hard to detect - one part in tens/hundreds of billions; linear frame dragging will be much much harder. We do have satellites on the other side of the sun - I think for heliological surveys - but not sure if any would be equipped (or could be equipped) with the sort of accuracy of clock that would be required.

[ajb]

The first place to look is here...

 

Clifford M. Will, The Confrontation between General Relativity and Experiment, Living Rev. Relativity 17 (2014), 4.

[DanMP]

 

 

Rotational frame dragging is hard to detect - one part in tens/hundreds of billions; linear frame dragging will be much much harder. We do have satellites on the other side of the sun - I think for heliological surveys - but not sure if any would be equipped (or could be equipped) with the sort of accuracy of clock that would be required.

 

The time difference, if linear f.d. is present, should be quite big, because the clock on Earth would suffer no kinematic time dilation ...

[swansont]

I imagined few more tests for relativity. Please tell me if they were already performed and with what outcome.

 

The first one is about 2 atomic clocks, one at the South pole (to be at rest in Earth's center frame) and the other in Space, around the Sun, on Earth's orbit (same distance, same speed) but far from Earth. So, both clocks are travelling with huge, same speed around the Sun, but the one on Earth "tick" slower due to gravitational time dilation caused by the Earth. This is the only difference, or the clock on Earth benefits from linear frame dragging and is not afected by the Earth movement around the Sun? Did anyone perform this, or at least apply relativity to see the outcome?

 

I think your approach here is flawed. Instead of asking if a specific experiment has been done (with the answer probably being no), you might be better served looking at the experiments we know that have been done, to see if the concept has been tested. Can you calculate how big of a clock difference you'd expect from frame dragging? If the prediction is smaller than our capability, you can eliminate those experiments from being attempted. No sense in looking to see if a part in 10^15 experiment has been done if the state of the art only allows for a part in 10^10

[DanMP]

...If the prediction is smaller than our capability, you can eliminate those experiments from being attempted. No sense in looking to see if a part in 10^15 experiment has been done if the state of the art only allows for a part in 10^10

What reasons do you have to believe that "the prediction is smaller than our capability"?!?

Did you apply relativity to see the outcome? Please do, before considering that is "no sense in looking".

 

 

The first place to look is here...

 

Clifford M. Will, The Confrontation between General Relativity and Experiment, Living Rev. Relativity 17 (2014), 4.

Did you find it there?

[swansont]

What reasons do you have to believe that "the prediction is smaller than our capability"?!?

Did you apply relativity to see the outcome? Please do, before considering that is "no sense in looking".

You apparently missed the "If" at the beginning of that sentence. So, let's have your calculation: how big is the expected effect?

[DanMP]

You apparently missed the "If" at the beginning of that sentence. So, let's have your calculation: how big is the expected effect?

 

If linear frame-dragging is total, the difference between the 2 clocks is quite big, the kinematic time dilation beeing experienced only by the clock far in space ...

 

You seem to be much better (and fond) than me in (of) relativity, so maybe you can apply GR to this and calculate the outcome.

[Phi for All]

 

You seem to be much better (and fond) than me in (of) relativity,

 

You're discussing atomic clocks with someone who builds atomic clocks for a living. For the US Naval Observatory. "Seem to be" is pretty understated.

[DanMP]

 

You're discussing atomic clocks with someone who builds atomic clocks for a living. For the US Naval Observatory. "Seem to be" is pretty understated.

 

Well than, I should expect from him the accurate outcome calculated using GR?

 

On the other hand, I have 2 more tests with atomic clocks, on Earth, at least one at one pole. It is feasible?

[swansont]

If linear frame-dragging is total, the difference between the 2 clocks is quite big, the kinematic time dilation beeing experienced only by the clock far in space ...

You seem to be much better (and fond) than me in (of) relativity, so maybe you can apply GR to this and calculate the outcome.

It's your thread. How can you claim the effect is big and yet have no calculation? How do you know it's big?

 

I am not familiar with this particular calculation. It's not something I've run across.

 

On the other hand, I have 2 more tests with atomic clocks, on Earth, at least one at one pole. It is feasible?

What are the tests?

[DanMP]

It's your thread. How can you claim the effect is big and yet have no calculation? How do you know it's big?

 

I am not familiar with this particular calculation. It's not something I've run across.

 

 

What are the tests?

I have reasons to believe that we do have total linear frame dragging, meaning that the clock on Earth would not experience any kinematic time dilation. And this is a big difference, because kinematic time dilation for speeds around 30km/s (Earth's speed around the Sun) is something very detectable. We will notice if it's missing

 

Unfortunately I am also not familiar with GR calculation. I hoped that someone here is ...

 

The other clock tests are with 2 atomic clocks, placed one on each pole or one at one pole and the other close to the equator, in order to detect very small seasonal/daily changes in clock rate. You know about such tests?

[imatfaal]

I have reasons to believe that we do have total linear frame dragging, meaning that the clock on Earth would not experience any kinematic time dilation. And this is a big difference, because kinematic time dilation for speeds around 30km/s (Earth's speed around the Sun) is something very detectable. We will notice if it's missing

 

Your reasons - until spelled out and preferably quantified are a chocolate teapot; ie not a lot of use. Perhaps think if there are any already pre-existing data which could double check your ideas - what about the signals from space probes that are out of earth's orbit

 

 

Unfortunately I am also not familiar with GR calculation. I hoped that someone here is ...

 

The standard time dilation is a result of the schwartzchild solution to the Einstein Field Equations; this is the vacuum solution around a non-spinning black hole - but is close enough to use. Frame dragging is a result of the Kerr Solution to the Einstein Field Equations; this is the vacuum solution around a spinning black hole.

 

To include the angular momentum AND the linear momentum seems an entirely more complex request as you have to insert in your idea the idea of an observer/test particle not only removed from the black hole (or whatever) but also in relative linear motion to the black hole; how do you do that - if I have read correctly parties agree on the ang mom and mass of objects but there are frames you can chose which negate linear momentum (the local frame) etc. And even saying that - which I am fully prepared to be quite wrong about - solutions to the EFE are very difficult to come by anyway.

 

Even saying all that - you solutions will include G - Newton's Constant which is only known to 4 decimal places (a relative uncertainty of 4.7 *10^-5)

 

 

This is technically the nicest way to work out the difference for a schwartzchild solution by the way - the r_s terms all have limited accuracy due to G as a component

 

[latex]\frac{f_1}{f_2}= \sqrt{\frac{1-r_s/r_2-\frac{(v_2/c)^2}{1-r_s/r_2}-(\frac{r_2 \omega_2}{c})^2}{1-r_s/r_1-\frac{(v_1/c)^2}{1-r_s/r_1}-(\frac{r_1 \omega_1}{c})^2}}[/latex]

The other clock tests are with 2 atomic clocks, placed one on each pole or one at one pole and the other close to the equator, in order to detect very small seasonal/daily changes in clock rate. You know about such tests?

 

What seasonal variations do you expect - are you thinking the difference in orbital velocity at perigee and apogee; cos that just aint gonna be discernable. And the pole v equator thing doesn't show up the variation we might like because the change in velocity is confounded by the change in gravitational potential. You could easily stick the figures from the net in the equation above to see what happens - I think the time dilation is equal to about one part in a thousand billion. However I think a certain persons clocks are down to about one part in a million billion so maybe a pair of super accurate clocks will see a significant difference.

 

Theoretically - for a fluid surface of a homogeneous rotating planet then there will be zero difference as the sea level will be a surface of equipotential (otherwise it would change to a lower energy state). But earth is not homogeneous so maybe you could work out a difference - not sure why you would want to though

[swansont]

I have reasons to believe that we do have total linear frame dragging, meaning that the clock on Earth would not experience any kinematic time dilation. And this is a big difference, because kinematic time dilation for speeds around 30km/s (Earth's speed around the Sun) is something very detectable. We will notice if it's missing

Unfortunately I am also not familiar with GR calculation. I hoped that someone here is ...

I don't care about what any pet theory of yours has to say; this is for discussing mainstream physics.

 

If you can't do the calculation, how do you know this is a big effect?

 

For the situation you describe, both clocks would have the orbital speed. We know it doesn't disappear for clocks on the ground because we compare them with satellite-based clocks all the time.

 

The other clock tests are with 2 atomic clocks, placed one on each pole or one at one pole and the other close to the equator, in order to detect very small seasonal/daily changes in clock rate. You know about such tests?

Why would they vary?

 

I am not aware of any atomic clocks at the south pole. I am fairly confident there are none at the north pole. On the surface, at least.

 

And the pole v equator thing doesn't show up the variation we might like because the change in velocity is confounded by the change in gravitational potential.

These effects cancel on the geoid. You only have to worry about elevation.

[ajb]

Did you find it there?

I do not look. I doubt the exact experiment you suggest is there, but their maybe things similar enough for you.

 

The paper is openly available, so you can check for yourself.

[DanMP]

...

The standard time dilation is a result of the schwartzchild solution ...

Sorry, I studied GR 25 years ago, didn’t use it at all, so I really cannot apply it.

 

...

What seasonal variations do you expect - are you thinking the difference in orbital velocity at perigee and apogee; cos that just aint gonna be discernable. And the pole v equator thing doesn't show up the variation we might like because the change in velocity is confounded by the change in gravitational potential. ...

I wrote:

I have reasons to believe that we do have total linear frame dragging, meaning that the clock on Earth would not experience any kinematic time dilation....

so, I'm not "thinking the difference in orbital velocity at perigee and apogee".

The speed of the "equator clock" and its altitude are constant, no?

 

Anyway, I'm asking if these 2 tests were performed.

[imatfaal]

Sorry, I studied GR 25 years ago, didn’t use it at all, so I really cannot apply it....

 

But you are constantly challenging GR and asking whether experiments have been undertaken to check remote and unlikely areas. And the "reasons" - is linked to a thread which gives no reasons just a misunderstanding of the concept of inertial frames.

 

Again - what seasonal / daily variations do you expect?

[DanMP]

 

If you can't do the calculation, how do you know this is a big effect?

If we have total linear frame dragging, the effect is big, as I explained. Why we should have it? My theory makes relativity very intuitive. Everything (time dilation, curved spacetime, frame-dragging, twin paradox, Shapiro time delay, static mass increase, all the peculiar things predicted by Einstein's relativity and confirmed by experiments) becomes easy to understand intuitively.

 

In the same way I don't need mathematics to explain why the speed of a passenger airplane doesn't have any influence inside the plane (no wind inside), I don’t need mathematics to make my predictions. (This was just an example of logic vs. mathematics. It has nothing to do with my theory.)

 

Anyway, my theory and my predictions are not important here. Only the experimental results are, and maybe, Einstein’s relativity predictions, because my theory is consistent with it, the only "mathematical difference" being that the invariance of c is explained, not postulated, so I expect that a correct application would give similar results.

 

 

For the situation you describe, both clocks would have the orbital speed. We know it doesn't disappear for clocks on the ground because we compare them with satellite-based clocks all the time.

I wrote "far" with bold:

...the other in Space, around the Sun, on Earth's orbit (same distance, same speed) but far from Earth.

Why would they vary?

 

I am not aware of any atomic clocks at the south pole. I am fairly confident there are none at the north pole. On the surface, at least.

The reason is impossible to understand without my theory.

It should be easy to do them, at least the one with the poles. I expect small variations in spring/autumn.

[Strange]

If we have total linear frame dragging, the effect is big, as I explained.

 

You have not "explained" this. You have asserted it. You appear to be incorrect. Show the maths that shows the effect is large, or withdraw the claim.

 

 

I don’t need mathematics to make my predictions.

 

You do if you are going to quantify them, even if only as "big".

 

 

Anyway, my theory and my predictions are not important here. Only the experimental results are, and maybe, Einstein’s relativity predictions, because my theory is consistent with it

 

So how do we test your theory if it is indistinguishable from GR?

 

 

I expect small variations in spring/autumn.

 

You will need to quantify these "small variations" so that the idea can be tested.

Edited February 11, 2016 by Strange

[DanMP]

But you are constantly challenging GR and asking whether experiments have been undertaken to check remote and unlikely areas. And the "reasons" - is linked to a thread which gives no reasons just a misunderstanding of the concept of inertial frames.

 

Again - what seasonal / daily variations do you expect?

Sorry for the confusing link. If I’ll decide to post my theory I will post a link to it here. Until then please focus your knowledge of GR on the first test or just leave it for now.

 

The daily variations I mentioned may be too small to detect, but the seasonal ones should be detectable. More when/if I will post my theory.

You have not "explained" this. You have asserted it. You appear to be incorrect. Show the maths that shows the effect is large, or withdraw the claim.

I have reasons to believe that we do have total linear frame dragging, meaning that the clock on Earth would not experience any kinematic time dilation. And this is a big difference, because kinematic time dilation for speeds around 30km/s (Earth's speed around the Sun) is something very detectable. We will notice if it's missing

Edited February 11, 2016 by DanMP

[Strange]

So you have no justification for the claim at all, other than your beliefs. That is not science.

[DanMP]

I do not look. I doubt the exact experiment you suggest is there, but their maybe things similar enough for you.

 

The paper is openly available, so you can check for yourself.

 

Thank you. I searched in it but didn't find the experiments I suggested.

So you have no justification for the claim at all, other than your beliefs. That is not science.

 

I have justifications, don't wory. Have patience ... And a little respect. You called my theory a waste of time, now you say that's based on beliefs, and all without even reading it. This is not nice. As I said, have patience.

 

Meantime, if you have any prediction about the first experiment, based on GR, please post it. If you don't have a mathematical prediction, why you dismiss my prediction? Base on what? On beliefs that relativity can't be intuitive maybe? Those are beliefs. Mine are logical justifications based on facts, not beliefs.

Edited February 11, 2016 by DanMP

[swansont]

If we have total linear frame dragging, the effect is big, as I explained.

OK. I misunderstood. I thought we were discussing relativity, not a pet theory of yours. I'll move this to speculations.

 

I wrote "far" with bold:

That would only matter if the effect "turned on" at some distance from the earth, and whether the remote clock were near or far would not affect the clock on the earth at all. We know that clocks near the earth are affected by gravitational and kinematic time dilation just as predicted by relativity. If this was a gradual effect, then there would be some effect seen for GPS satellites.

 

If a clock on the earth were to be unaffected that means that all frequencies would be unaffected — any spectroscopic measurements of signals from outside the earth would see this shift. I would expect there to be a discrepancy with doppler shift measurements for sources where we had an independent way of determining speed. This is true of probes we've sent out. AFAIK, none of them suddenly see a discrete shift as this frame dragging turned on.

[DanMP]

OK. I misunderstood. I thought we were discussing relativity, not a pet theory of yours. I'll move this to speculations.

Don't discuss my theory than. Just use GR to calculate the outcome of the first test proposed, if you can, or let it there for someone who can, or for someone able to do the test.

 

That would only matter if the effect "turned on" at some distance from the earth, and whether the remote clock were near or far would not affect the clock on the earth at all. We know that clocks near the earth are affected by gravitational and kinematic time dilation just as predicted by relativity. If this was a gradual effect, then there would be some effect seen for GPS satellites.

No gradual effect. Total, until somewhere far from Earth, or nothing. And is not a "turn of" of all kinematic time dilation. Just the one caused by the orbital speed around the Sun.

 

If a clock on the earth were to be unaffected that means that all frequencies would be unaffected — any spectroscopic measurements of signals from outside the earth would see this shift. I would expect there to be a discrepancy with doppler shift measurements for sources where we had an independent way of determining speed. This is true of probes we've sent out. AFAIK, none of them suddenly see a discrete shift as this frame dragging turned on.

Please elaborate. I don't understand why it should be a shift.

 

 

How you explain rotational frame dragging if the frame that rotates doesn't travel with the Earth. (This is not an argument in my theory!)

Edited February 12, 2016 by DanMP

[swansont]

Don't discuss my theory than. Just use GR to calculate the outcome of the first test proposed, if you can, or let it there for someone who can, or for someone able to do the test.

The kinematic term is just 1/2 v^2/c^2, so if dilation from the motion about the sun were "turned off" that would change the clock by 5 x 10^-9. The clock far from earth would be faster by 7 x 10^-10 for being out of the gravitational well.

 

No gradual effect. Total, until somewhere far from Earth, or nothing. And is not a "turn of" of all kinematic time dilation. Just the one caused by the orbital speed around the Sun.

What other speed is there to consider?

 

Please elaborate. I don't understand why it should be a shift.

You just said there's no gradual effect. All or nothing. So there should be a change in frequency when it changes from one to the other. At what distance does this transition occur?