# Gravity slows down time.

So if the traveling clock is correct, it should expect to see the earth in a different position from the stay at home twin.

Yet it does not.

So, you and other SR addicts need to explain how the traveling clock is correct and yet the earth is in exactly the same position for both clocks when they are re-united.

That implies the traveling twin experienced less time and did not experience less time, which is a logical contradiction.

Both clocks are correct in there own FoRs....It is only in relation to an outside FoR that time dilation is obvious.

Whatever FoR that clock is in, in relation to the other clock is irrelevent.

What is relevent is the Equivelance principal and the part it plays with the twin paradox, which isn't a paradox at all.

Assume two observers are at the same place on the earth.

One climbs a very high pole and remains there for a very long time.

Eventually, the observer climbs down.

That high observer is older since time went faster for him/her.

The land based observer is younger.

So, the high observer says the time on his clock is 12:00 am and the land based observer claims time on his clock is 12:00pm.

That means the high observer claims the earth is in a different rotational position from the land based observer, which is a contradiction.

Can anyone resolve this?
Forgive me, Chinglu, but your scenario 'contradiction' is a 'contrived' one, not an absolute one. Consider:

The original second standard of time was the lower altitude clock reference, yes? So all variations are immediately relative to that 'standard', derived from some third-party reference beforehand. So naturally the time on the upper clock when brought back down will be the CHANGED-FROM-STANDARD as set beforehand ccording to the LOWER position. Period. That's all that you can deduce from your scenario as stated.

You can see this more clearly if you modify your scenario so that BOTH CLOCKS are moved to upper position and then later both brought down again. They will AGREE with each other, and the only reason you know that BOTH are WRONG is that you take reference from the Earth-Sun and/or Earth-rotation 'standard as a THIRD PARTY REFERENCE which both clocks are compared to and found incorrect even though both agree with each other (in modified scenario).

So it's trivial results/conclusions because a third party reference must also be used if you realize that both clocks can change if moved up and back etc. So, moving just one clock merely DEFAULTS to the standard second-rate reference of the lower clock when starting out with THAT 'pre-determined standard' as derived from the third party reference sun-Earth system initially used to get that 'pre-determined' standard at lower position.

Anyhow, good luck and keep thinking, Chinglu! Bye.

So if the traveling clock is correct, it should expect to see the earth in a different position from the stay at home twin.

Yet it does not.

Yes, it does see Earth in a different position, it has to because it has experienced time dilation. There is nothing else to explain.

Please link to the specific paper/article/page which computes the relevant geodesics and worldline lengths. Until such time as you do that I do not believe you.

I asked you to provide the calculations for precisely that. My request is "on task". It is your inability to respond which is not on task.

Provide the calculations, which you now claim are freely available.

I have provided links.

So, you have failed to address the issue of the high observer and low observer comparing clocks.
You can also do this with the twins paradox.

Now, I will ask you again, which you continue from answering.

When a clock is reunited with a time dilated clock, do they agree or disagree on the earth's position.

If both of their clocks are correct as claimed by SR/GR, then they must disagree on the one earth's position which is a contradiction.

When a clock is reunited with a time dilated clock, do they agree or disagree on the earth's position.

Clocks don't get "dilated".
Clocks do not measure position.

Both clocks are correct in there own FoRs....It is only in relation to an outside FoR that time dilation is obvious.

Whatever FoR that clock is in, in relation to the other clock is irrelevent.

What is relevent is the Equivelance principal and the part it plays with the twin paradox, which isn't a paradox at all.

Let's try to get your reasoning figured out.

If both clocks are correct, how can they also agree on the earth's position since the clocks must also reflect the earth's position.

Yet the clocks are different meaning they must disagree on the earth's position.

See the contradiction yet?

Yes, it does see Earth in a different position, it has to because it has experienced time dilation. There is nothing else to explain.

That would mean two observers standing at the same spot would see the sun in a different position in the sky.

So, are there two suns?

Forgive me, Chinglu, but your scenario 'contradiction' is a 'contrived' one, not an absolute one. Consider:

The original second standard of time was the lower altitude clock reference, yes? So all variations are immediately relative to that 'standard', derived from some third-party reference beforehand. So naturally the time on the upper clock when brought back down will be the CHANGED-FROM-STANDARD as set beforehand ccording to the LOWER position. Period. That's all that you can deduce from your scenario as stated.

You can see this more clearly if you modify your scenario so that BOTH CLOCKS are moved to upper position and then later both brought down again. They will AGREE with each other, and the only reason you know that BOTH are WRONG is that you take reference from the Earth-Sun and/or Earth-rotation 'standard as a THIRD PARTY REFERENCE which both clocks are compared to and found incorrect even though both agree with each other (in modified scenario).

So it's trivial results/conclusions because a third party reference must also be used if you realize that both clocks can change if moved up and back etc. So, moving just one clock merely DEFAULTS to the standard second-rate reference of the lower clock when starting out with THAT 'pre-determined standard' as derived from the third party reference sun-Earth system initially used to get that 'pre-determined' standard at lower position.

Anyhow, good luck and keep thinking, Chinglu! Bye.

I am afraid you failed to address the time dilation component of the experiment that is so much a part of GR/SR.

Until you do that, you are not talking about this experiment.

Clocks don't get "dilated".
Clocks do not measure position.

Are you now claiming SR/GR time dilation is false?

Second, are you claiming the time on an earth based clock does not accurately reflect the correct earth rotation and orbital positions?

RPenner is smart.

He does not post here because he knows he will be forced into a contradiction if he assumes SR/GR is true.

Are you now claiming SR/GR time dilation is false?

Nope, simply that you don't understand an iota of relativity and that you post nonsense.

Second, are you claiming the time on an earth based clock does not accurately reflect the correct earth rotation and orbital positions?

Nope, just that clocks don't measure position , contrary to your crank claims. <shrug>

I am afraid you failed to address the time dilation component of the experiment that is so much a part of GR/SR.

Until you do that, you are not talking about this experiment.

Hi Chinglu.

Mate, if you re-read my post again, you will see that I indeed did address the time dilation aspect. I even addressed the logics (and even modified the scenario to highlight it) which demonstrated that your 'contradiction' was a 'contrived' one based on trivial observation/conclusions, as explained in my post.

Look, I will go even further and prove to you that it is a trivial observation. Consider further where sun-dials are used instead:

The two 'clocks systems' are identical SUN-DIALS. One is moved up and then back as per your original scenario, and then we use those same sun-dials to 'read off' the position of the sun when it is directly overhead. What do we find? The two sun-dials AGREE that the sun is overhead because the 'shadow pointer' is the same for both sun-dials irrespective of what they have experienced beforehand whatever the altitude.

So you see, 'time dilation' is only relevant in the 'mechanical clock' system dependent on pre-determined 'tick rate' according to sun-Earth system 'seconds rate' for the lower position before any motion of any clock up and back.

In both cases, for mechanical clocks and sun-dial types, any 'time dilation' becomes moot when both are again at the same lower position and using that SAME SUN-EARTH system for its reference point FROM THAT MOMENT 'anew', irrespective of any different 'counts' of mechanical mechanical clock or any prior motion of sun-dial clock.

See?

At start, in the mechanical clocks case, the 'standard' is that of the lower position for BOTH clocks. Any 'incorrect' difference is logically and automatically again 'overwritten and understood' when the moved clock is again returned to that 'correct' STANDARD from which both started.

And at start and throughout, in the sun-dial clocks case, there is NEVER any 'difference' in the shadows (except from TRANSIENT trivial angular slanting of light rays from same sun position going to different altitudes), and so both sun-dial clocks will agree at every stage of the experiment, including that the sun is overhead for both of the reunited sun-dials at 12 midday.

Your 'conclusions' are rooted in 'contrived trivialities', and not in the logical/physical essentials which I have actually highlighted in my previous and present post.

Good luck, Chinglu, and better luck in your other discussions.

Hi Chinglu.

Mate, if you re-read my post again, you will see that I indeed did address the time dilation aspect. I even addressed the logics (and even modified the scenario to highlight it) which demonstrated that your 'contradiction' was a 'contrived' one based on trivial observation/conclusions, as explained in my post.

Look, I will go even further and prove to you that it is a trivial observation. Consider further where sun-dials are used instead:

The two 'clocks systems' are identical SUN-DIALS. One is moved up and then back as per your original scenario, and then we use those same sun-dials to 'read off' the position of the sun when it is directly overhead. What do we find? The two sun-dials AGREE that the sun is overhead because the 'shadow pointer' is the same for both sun-dials irrespective of what they have experienced beforehand whatever the altitude.

So you see, 'time dilation' is only relevant in the 'mechanical clock' system dependent on pre-determined 'tick rate' according to sun-Earth system 'seconds rate' for the lower position before any motion of any clock up and back.

In both cases, for mechanical clocks and sun-dial types, any 'time dilation' becomes moot when both are again at the same lower position and using that SAME SUN-EARTH system for its reference point FROM THAT MOMENT 'anew', irrespective of any different 'counts' of mechanical mechanical clock or any prior motion of sun-dial clock.

See?

At start, in the mechanical clocks case, the 'standard' is that of the lower position for BOTH clocks. Any 'incorrect' difference is logically and automatically again 'overwritten and understood' when the moved clock is again returned to that 'correct' STANDARD from which both started.

And at start and throughout, in the sun-dial clocks case, there is NEVER any 'difference' in the shadows (except from TRANSIENT trivial angular slanting of light rays from same sun position going to different altitudes), and so both sun-dial clocks will agree at every stage of the experiment, including that the sun is overhead for both of the reunited sun-dials at 12 midday.

Your 'conclusions' are rooted in 'contrived trivialities', and not in the logical/physical essentials which I have actually highlighted in my previous and present post.

Good luck, Chinglu, and better luck in your other discussions.

Hi Undefined .. Mate .. Aussie perhaps ?

I've been reading this thread. I like your explanation concerning the sundails. One of them could have travelled 'round the universe for all we know - but at the point where it is at the bottom next to the other it presents an identical 'machine' as the other (unless it was deformed - trivial) right ? No part of it's 'mechanics' have changed. So irrespective of what it's done in the past, it agrees with the other. Am I on the right track ?

Now bear with me here, because I'm still working through it .. I think Chinglus reference to sundails was therefore somewhat wrong, irrelevant perhaps, but as far as mechanical clocks are concerned, his point is that as the go up / down their mechanics should be affected by time dilation.

A different thing, no ?

Hi Undefined .. Mate .. Aussie perhaps ?

I've been reading this thread. I like your explanation concerning the sundails. One of them could have travelled 'round the universe for all we know - but at the point where it is at the bottom next to the other it presents an identical 'machine' as the other (unless it was deformed - trivial) right ? No part of it's 'mechanics' have changed. So irrespective of what it's done in the past, it agrees with the other. Am I on the right track ?

Now bear with me here, because I'm still working through it .. I think Chinglus reference to sundails was therefore somewhat wrong, irrelevant perhaps, but as far as mechanical clocks are concerned, his point is that as the go up / down their mechanics should be affected by time dilation.

A different thing, no ?
Yes, Aussie, mate.

And yes, that was the point of using the sun-dials to illustrate/highlight the point that in the mechanical clocks case time dilation does occur BUT that the return to the lower position makes that moved clock wrong, because it no longer keeps to the pre-agreed 'standard timing' of the lower position whence the scenario started. And the point that that pre-agreed 'standard' already had regard to the actual positions of Sun-Earth system from that common starting point, so any later 'disagreement' is only about 'counting total' and not actual Sun_Earth position, because the Sun-Earth position was essentially always the third party 'standard' which any clock in that lower position MUST agree with if it is to be used in the first place. The sundial example merely reduced the triviality/logics to the 'reductio ad absurdum' case where the Sun-Earth 'standard' was always the one to compare any clock TO, irrespective of whether mechanical or sun-dial, and only those that agree with the lower position 'starting point' standard can be trusted FOR that position AT that time of day etc etc.

Gotta go. I hope that rushed clarification made more obvious my intention/purpose in adding the "both clocks moved up and back" and the "two sun-dials" modifications as illustrations of the essential logics/trivialities involved?

Cheers, Lakon!

Yes, Aussie, mate.

Me too - downtown Sydney, Hills area. You ?

And yes, that was the point of using the sun-dials to illustrate/highlight the point that in the mechanical clocks case time dilation does occur BUT that the return to the lower position makes that moved clock wrong, because it no longer keeps to the pre-agreed 'standard timing' of the lower position whence the scenario started. And the point that that pre-agreed 'standard' already had regard to the actual positions of Sun-Earth system from that common starting point, so any later 'disagreement' is only about 'counting total' and not actual Sun_Earth position, because the Sun-Earth position was essentially always the third party 'standard' which any clock in that lower position MUST agree with if it is to be used in the first place. The sundial example merely reduced the triviality/logics to the 'reductio ad absurdum' case where the Sun-Earth 'standard' was always the one to compare any clock TO, irrespective of whether mechanical or sun-dial, and only those that agree with the lower position 'starting point' standard can be trusted FOR that position AT that time of day etc etc.

Gotta go. I hope that rushed clarification made more obvious my intention/purpose in adding the "both clocks moved up and back" and the "two sun-dials" modifications as illustrations of the essential logics/trivialities involved?

Cheers, Lakon!

Nope - it didn't but it's probably more my fault than yours. Gonna read through your post and earlier ones a few more times .. see if I can make sense of this.

Cheers for now.

I am saying frequency clocks have defects in measuring time just as sundials do.

We have to make "GPS" corrections to sundial clocks given the season or latitude.

Likewise, frequency clocks also have defects based on conditions.

For example, frequency is known to change based on gravity. It is just a fact.

So, a frequency measuring device such as a frequency clock, would certainly contain this defect.

Why do frequency clocks have defects in measuring time? because the frequency changes based on grav potential and speed... does that really indicate the increment of time is changing?

The way I understand it, the whole TD system was brought about by atomic oscillating clocks changing frequency. Whether this is enough proof to say time is actually varying because the frequency changes is a whole different story, but, because we use those types of clocks in our technology compensation/synchronisation is required. If I was on the jury panel I would need more proof of this TD phenomena and would demand a mechanical clock experiment to be conducted to verify TD. Do mechanical clocks display this TD effect? If no, I would start considering a different physical reason as the culprit of TD. If yes, I would say TD is well verified. The mechanical clock experiment would have to be meticulously constructed, got any links to read on TD and mechanical clocks? IMO if TD is affecting one type of timing technology and it is a true physical effect then it has to affect all types of timing technologies to be strictly verified, or am I missing some understanding in my logic? Well at least all types of timing technologies that dont require certain environmental effects eg. pendulums require a constant strength of gravity.

http://science.howstuffworks.com/atomic-clock.htm

This locked frequency is then divided by 9,192,631,770 to give the familiar one pulse per second required by the real world.
Awesome website.

Is frequency changing enough to say time is actually varying because the physical parameters/environment of the clock are changing? Im no expert on atomic clocks or time, I can imagine they are a robust method for tracking the increment of a second if all the physical parameters/environment remain constant.

Me too - downtown Sydney, Hills area. You ?

Cheers for now.

Me three!
In the Eastern suburbs of Sydney in the beautiful beach side suburb of Maroubra.

Me three!
In the Eastern suburbs of Sydney in the beautiful beach side suburb of Maroubra.

Nice - so no longer a 'paddo' boy ?

That would mean two observers standing at the same spot would see the sun in a different position in the sky.

No, they wouldn't, the ship that left earth and returned would see the same sun, but their onboard guidance system would be off in the location of the sun due to time dilation. Why is this so hard for you to understand.

So, are there two suns?

Of course not, that is just silly.

Nice - so no longer a 'paddo' boy ?

Born and raised in Paddington!