According to wikipedia,

"Technically, neither space nor objects in space move. Instead it is the metric governing the size and geometry of spacetime itself that changes in scale. Although light and objects within spacetime cannot travel faster than the speed of light, this limitation does not restrict the metric itself. To an observer it appears that space is expanding and all but the nearest galaxies are receding into the distance. "

I kind of like the idea that length scales changes over time so that the universe appears to expand even if there is no movement, if this is how it is supposed to be interpreted.

Now in general relativity we have that time, energy and velocity of light basically co-variates within a gravitational field in a special way that makes the laws of physics appear the same even if different observers at different spatial locations and sometimes at different velocities will sometimes disagree.

Is the expansion of space thought of as a similar scenario where observes in different temporal locations agrees on the laws of physics but may disagree on the length scales used in the physical expression?


1.Can we say that what we perceive as one meter today was perceived as less then one meter at earlier epochs and this is why we a little bit sloppy says that "space is expanding"?

2.If the answer to question 1 is "yes",are there any variables co-variating with the change of length scales? I mean in a gravitational field due to general relativity we have the rate of time, velocity of light and energy (gravitational redshift, blueshift) covariating in a special way, do we have something similiar when we look at "expansion of space"?


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