Base time.

[RICHARDBATTY]

Have any calculations been done to estimate the amount of time dilation caused by earths movements. The general idea of this thread is to find out how much difference there could be between the base natural passing of time, and the passing of time as we experience it. I think a good place to start would be to find out our exact amount of movement in relation to a fixed point. Has anyone heard of any work done on this subject.

[swansont]

Name the fixed point. Then explain why that's not arbitrarily defined, and why it matters.

 

Timekeeping is generally done in the ECI, or earth-centered inertial frame, since that is most convenient for us. The rotation of the earth does not cause deviations, since the time dilation contribution from the motion is cancelled by the change in gravitational redshift that depends on the oblateness.

[RICHARDBATTY]

Fixed point any. It may be defined. Cause I want to know.

 

I was not talking just on the rotation of the earth. You would have to inclued motion in a universal sense eg: solar orbit, galactic orbit and super galactic orbit.

[timo]

Has anyone heard of any work done on this subject.

Yes, a very famous theory (General Relativity) is based on the assumption that there is no "natural" system of reference and thus no "natural" passing of time.

[RICHARDBATTY]

Thanks for the help.

[J.C.MacSwell]

Name the fixed point. Then explain why that's not arbitrarily defined' date=' and why it matters.

 

Timekeeping is generally done in the ECI, or earth-centered inertial frame, since that is most convenient for us. The rotation of the earth does not cause deviations, since the time dilation contribution from the motion is cancelled by the change in gravitational redshift that depends on the oblateness.[/quote']

 

Doesn't this mean that you "age" the same at the Poles as the equator?

 

Wouldn't you "age" faster at the center of the earth?

 

EDIT: Or assuming constant density of the Earth everything inside or on the surface would "age equally and someone at the top of (say) Everest, above this surface, would "age" faster?

[mezarashi]

I don't have any links for you, but I say confidently to you that indeed there have been tests on this time dilation effect. Some accidently actually. For example clocks on aircraft have been known to become desynced with those on the ground, and need to be adjusted every so often, but more importantly, I believe that NASA has put some atomic clocks on space shuttles or stations before and they have proved to run slower than the references on Earth, so if that's enough experimental proof for ya. I don't have the numbers though I'm sure you can search the literature from there, goodluck

 

Oh, I reread your question again, and erm... I think that your "reference" should generally be Earth, thus any experiment to time dilation should be with reference to the Earth's surface . What else are we going to do?

[swansont]

Doesn't this mean that you "age" the same at the Poles as the equator?

 

Wouldn't you "age" faster at the center of the earth?

 

EDIT: Or assuming constant density of the Earth everything inside or on the surface would "age equally and someone at the top of (say) Everest' date=' above this surface, would "age" faster?[/quote']

 

Yes. Basically you have to adjust your clocks for altitude, but not latitude.

[swansont]

I don't have any links for you' date=' but I say confidently to you that indeed there have been tests on this time dilation effect. Some accidently actually. For example clocks on aircraft have been known to become desynced with those on the ground, and need to be adjusted every so often, but more importantly, I believe that NASA has put some atomic clocks on space shuttles or stations before and they have proved to run slower than the references on Earth, so if that's enough experimental proof for ya. I don't have the numbers though I'm sure you can search the literature from there, goodluck

[/quote']

 

Any "desyncing" would be in the course of an experiment, or due to a problem with the clock. The Hafele-Keating experiment saw a net effect of a few hundred nanoseconds (at most). A run-of-the-mill clock on a plane isn't going to notice that. A good (i.e. atomic) clock is going to have to be compensated, but this wouldn't surprise anyone. These days you can resync quite easily - GPS. (and GPS clocks are a good example of relativity in action)