Quote:
Originally Posted by troutman
Just like the galaxies painted on to the surface of this balloon aren't moving but are getting farther apart, because the balloon is expanding, the real galaxies in the Universe are getting farther and farther away from one another (and, therefore, from us), but due to the expansion of spacetime
But the stuff that's 46.6 billion light years away now was much closer in the past, and the total distance that light has traveled to reach us is 13.7 billion light years; it's just that the Universe has kept on expanding throughout that light's journey.
That's why the light gets redshifted; that's why the galaxies look like they're moving away from us. But what we're seeing is actually the expansion of the Universe, and the expansion continues before the light was emitted, during its travels to us, and after we've received it; and that's how the observable Universe can be 93 billion light years across, even though it's only 13.7 billion years old!
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funny thing is this doesn't answer T@T's question at all. I read a lot about physics and still can't quite grasp how lightspeed effects the actual shape of the universe. below is a picture of the universe from hubble showing the thermodynamic state of matter, except that it's coming from different sources from different distances so this isn't really what things look like, and that's what T@T was asking or hinting at.
