Based on inflation theory, the universe would have grown so fast during this exponential doubling that in only an eyeblink the entire realm visible to telescopes today could have burst forth from a piece of the big bang that was no larger than a proton. Guth was so content with this "basement universe" idea. If you could compress 25 pounds of matter into a 10^-24 cm, making a mass around 10^75 times the density of water and certain conditions were met, a bubble of a false vacuum or "child universe" would be formed *. From the outside it would look like a black hole. From the inside, it would look like an inflating universe. The child universe would slip sort of sideways to our own and expand into its own space-time (Overbye, 1991)
The Shape of The Universe
Knowing there are galaxies other than where we live, understand the beginning through big bang, and searching black holes to get a deeper look in singularity are daily dose of cosmology works, but cosmologists nowadays taking this task to another level by trying to figure out the shape of the universe. It is called cosmic topology.
In the last two decades, when computer modelling gets more and more advanced, many researchers suggest many theories and models of the universe. One amongst the popular is tiling method. Not quite different with what we do in school when we want to measure the area of irregular shapes. It depends in how big the universe itself. If universe was finite, we would see a ghost image of ourselves, because some light would hit us again after winding around and create a ghost images in several places. It would trick our mind when applied in a bigger scale because light might take longer route. Says the ghost image of Milky Way could be mistakenly recognized as other distant galaxy.
Remember classic astronomy says that when we look up at the sky, we see the past? because light from faraway object needs time to reach us, what we see now might be things that happened in million years ago.
So when we see that ghost image, it might be us seeing ourselves or our home (Milky Way) but the older version. Because light that sent from older "us" needs time to reach us again after winding around the finite space of universe (if the universe is indeed finite).
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The tiling reveals that a finite space looks like a hall of mirrors and the kaleidoscope of images can reveal how the tiles fit together. The farther away the tile, the longer it takes light to get to observers and so the older the image they'd see. "
The smallest spaces are the most important to cosmology. If the volume of space is huge, then we won't be able to see far enough into the universe to perceive the topology. If instead the volume of space is small, then we just may be able to see far enough into the universe to discover the shape of space."
(Levin, 2002)
The tiling would be like this:
