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This might be a silly question to ask but still I had to ask. we know that gravitational force between two galaxies are quite less as compared to the dark energy. so two galaxy are separated at speed faster than the speed of light. but if this holds true then the light from the nearby galaxy will never reach as they will be separating faster than the speed of light. So then how can we observe the nearby galaxy as the light would never reach us?

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  • $\begingroup$ Your conclusion is correct, your initial conditions, however, are not. Distances between galaxies are, in generatl, increasing, but not with velocities above the speed of light limit (which is really, a limit.). $\endgroup$ – Clever Jun 11 '16 at 7:37
  • $\begingroup$ Hi. There is a limit that allow us to see objects receding from us faster than light. That is because, although at the beginning the light travels in a region where the expansion is faster than it's speed, as it moves closer, it reaches a point where the expansion matches it's speed and then becomes smaller, so, it can reach us, even if it has a great redshift. After a speed limit, though, the light that will reach us will be red shifted to the background radiation, so it will not be distinguishable. $\endgroup$ – Constantine Black Jun 11 '16 at 7:41
  • $\begingroup$ (Unless I'm mistaken), the light from that distant galaxy, if it leaves the galaxy today that light will never reach us. The light from the distant galaxy that we see in the sky, the light we see left that galaxy billions of years ago when it was closer to us and not moving away as fast. $\endgroup$ – userLTK Jun 11 '16 at 7:51

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