ocalhoun

So, in our universe, everything appears to be moving away from us, and the farther away from us something is, the faster it appears to move away from us.

Let's say that we are at point A, and we are looking at three different distant galaxies: galaxy B, C, and D.

C is twice as far away as B, and D is twice as far away as C (which means that D is for times as far from A as B is).

Now, B is so far away that it appears to be moving away at .5 times the speed of light (c).

Going by the normal formula, C should be twice that speed and D should be four times that speed.

But, that would make the apparent speeds of C and D 1c and 2c, respectively!

I don't understand what is wrong here...

My guesses:

1: Not a real violation of special relativity, because space is expanding, nothing is really moving

2a: The equation for finding how fast something should be receding becomes non-linear for long distances

2b: The equation for finding how fast something should be receding needs to account for relativity theory when using such large values in order to get a correct result.

But, if the solution is one of the 2's, wouldn't that mean that (from our point of view, at least) many of the distant objects in the universe would seem to clump together more than they should? (Because the furthest ones are slowed down by the limitations of the speed of light.)

Is it one of my guesses, or something else entirely?

Let's say that we are at point A, and we are looking at three different distant galaxies: galaxy B, C, and D.

C is twice as far away as B, and D is twice as far away as C (which means that D is for times as far from A as B is).

Now, B is so far away that it appears to be moving away at .5 times the speed of light (c).

Going by the normal formula, C should be twice that speed and D should be four times that speed.

But, that would make the apparent speeds of C and D 1c and 2c, respectively!

I don't understand what is wrong here...

My guesses:

1: Not a real violation of special relativity, because space is expanding, nothing is really moving

2a: The equation for finding how fast something should be receding becomes non-linear for long distances

2b: The equation for finding how fast something should be receding needs to account for relativity theory when using such large values in order to get a correct result.

But, if the solution is one of the 2's, wouldn't that mean that (from our point of view, at least) many of the distant objects in the universe would seem to clump together more than they should? (Because the furthest ones are slowed down by the limitations of the speed of light.)

Is it one of my guesses, or something else entirely?