So I was watching the “The Hubble Ultra Deep Field in 3D” video on youtube, and based on the commentary (around 2:20) some of the galaxies are moving away from us at faster than the speed of light. I’m not sure that was supposed to be possible, but let’s say it is.
Now, if the galaxy is moving away at the speed of light(c)+x, x being some tiny amount. If the galaxy emits a photon which travels at the speed of light in the opposite direction, it would still be traveling away from us at x. How are we able to detect something that is moving away from us?
So let’s pretend that we can’t detect something moving away from us at faster than the speed of light. Now, the universe is supposedly filled with dark matter, but it can’t be detected. What if all of these galaxies moving away at faster than the speed of light are the dark matter? They exist, we know they should exist, but we just can’t see them.
It seems to me, that there are a lot more galaxies out there than we could even see…