Cosmic Fun: Random Ramblings in Modern Cosmology: The Size of the Universe

The following ideas are primarily mine alone, the good, the bad and the ugly, albeit based on and influenced by reading multi volumes of tomes in modern cosmology. However, I’m also quite sure that numerous others have quite independently thought somewhat similar, if not exact, thoughts as well. Therefore, I’ll take no credit for being right, if I don’t get blamed for being wrong!

THE SIZE OF THE UNIVERSE

Our Universe is big. It’s really awesomely large in comparison to any normal standard measuring units we care to use. But is it as large as we’ve been led to believe?

We’ve read that if we live in a closed Universe then in theory, light reflecting off the back of our head would travel the circumference of our Universe and back to us and thus we could view the back of our heads! However, we probably wouldn’t because there’s all this mass in our Universe which has gravity, and as we know, gravity can bend light according to the Theory of General Relativity. Such deflection would probably throw that beam of light off of an otherwise true path and thus miss us on the go-round. In a similar fashion, very dense objects can act like a lens and split an image of something behind into two identical images – gravitational lensing I believe it’s called. The question arises, is much of what we observe in our observable universe merely multiple images of far fewer objects? That is, say we view galaxy A or cluster of galaxies A. Perhaps another galaxy B or cluster of galaxies B off in some other direction isn’t another group of objects, but the same galaxy A or cluster of galaxies A, albeit viewed from a different angle. I understand such images would be termed ‘ghost galaxies’. The upshot is that the Universe could contain far fewer actual objects than we actually count. Thus, we don’t need anywhere near the sort of space that we think must exist. If our Universe is akin to a hall-of-mirrors, then perhaps it’s a lot smaller than we think. That would have massive implications for cosmological theorizing. Of course even a Universe that’s vastly smaller than we think it is is still really awesomely large in comparison to any normal measuring units we care to use.