Can we make a standard Universe clock?

[physalpha]

Is it possible to make an absolut standard Universe clock?
I think it's not easy to make that knid of clock.
The effects of gravity and velocity should be removed.
If there were a point not moved and no gravity in the Universe, we could measure the time exactly.
In the Earth, are we able to do that work?
Moreover recently some researcher say physical constants have been varied.

 

[marcus]

Is it possible to make an absolut standard Universe clock?
I think it's not easy to make that knid of clock.
The effects of gravity and velocity should be removed.
If there were a point not moved and no gravity in the Universe, we could measure the time exactly.
In the Earth, are we able to do that work?
Moreover recently some researcher say physical constants have been varied.

only approximately, not perfectly.

Get way far out away from any galaxy or cluster of galaxies so that you don't have the effect of being down in a gravity well.

Then adjust your motion so that when you measure the microwave background (the most ancient light, from about year 380,000) there is no Doppler hotspot in the sky. That is, you are not moving with respect to ancient light. This adjustment is only possible to within about 1/1000 of one percent, I guess. You can only say that you are approximately at rest.

 

[Chronos]

Some reserchers are still promoting MOND. Time is relative. There is no way to assign a unique coordinate system to any 'clock' under general relativity.

 

[Imax]

I don’t think it’s possible to make an absolute standard Universe clock.

If there was no gravity in the Universe, then there would be no matter. Mass defines space-time. If you were a point in empty space and you had no mass and no volume, then there would be no reference points to establish x, y, z coordinates, and no way to establish how those coordinates change with time.

Imax

 

[Chronos]

A good read here to consider: http://plato.stanford.edu/entries/spacetime-theories/

 

[physalpha]

Then which one is correct?
The standard is the same velocity state as the Universe expansion.
The standard is not moving state.

 

[marcus]

only approximately, not perfectly.

Get way far out away from any galaxy or cluster of galaxies so that you don't have the effect of being down in a gravity well.

Then adjust your motion so that when you measure the microwave background (the most ancient light, from about year 380,000) there is no Doppler hotspot in the sky. That is, you are not moving with respect to ancient light. This adjustment is only possible to within about 1/1000 of one percent, I guess. You can only say that you are approximately at rest.

Then which one is correct?
The standard is the same velocity state as the Universe expansion.
The standard is not moving state.

there is no difference. In Cosmology, the ancient light of the CMB is the standard of rest.
If you have no doppler hotspot in the CMB sky, then you are at rest with respect to the ancient matter that emitted the ancient light.
It has been called "comoving with the expansion" or "comoving with the Hubble flow" but those are just words that mean the same thing as being at rest relative to the Cosmic Microwave Background.

In cosmology one does a change of coordinates so that the data is recorded as if from an observer at rest. We deduct for the Earth motion around sun and we deduct for the the sun motion relative to CMB. We know that the sun is going 380 km/second in a certain direction relative to CMB (because can see doppler hotspot around constellation Leo the Lion.)
So before recording the other CMB data or the redshift data we can correct for the sun's 380 km/second motion. Then the data is AS IF SEEN BY OBSERVER AT REST.

To make a standard clock you should also correct. In effect you should locate the clock on a body which is at rest relative to the universe's ancient light.

Do not think of expansion as motion outwards from a center. Expansion is the increase of distance between objects which are at rest with respect to CMB. It has no center. There is no "outwards" motion, only increase of distance between objects at rest.

Think of points on a balloon surface---each one stays at the same latitude longitude, each one is at rest, but distances between them grow. They do not know of another dimension. Each one can only observe his neighbors on balloon surface. He can not observe another direction inside or outside the balloon. Nor can we observe any other direction besides our 3. And so for us the distances between stationary points can increase and that is just how it is. General Relativity allows geometry to change so it is not too strange that this happens.