Delta4Embassy
Gold Member
What shape is the universe
"There are three main flavors that scientists consider: positively curved, negatively curved, and flat. We know it exists in at least four dimensions, so any of the shapes we are about to describe are bordering on Lovecraftian madness geometry, so fire up your madness abacus. Ya! Ya! Cthulhu ftagen.
A positively curved universe would look somewhat like a four-dimensional sphere. This type of universe would be finite in space, but with no discernible edge. In fact, two distant particles travelling in two straight lines would actually intersect before ending up back where they started.
You can try this at home. Grab a balloon and draw a straight line with a sharpie. Your line eventually meets its starting point. A second line starting on the opposite side of the balloon will do the same thing, and it will cross your first line before meeting itself again.
This type of universe, conveniently easy to imagine in three dimensions, would only arise if the cosmos contained a certain, large amount of energy.
To be positively curved, or closed, the universe would first have to stop expanding – something that would only happen if the cosmos housed enough energy to give gravity the leading edge. Present cosmological observations suggest that the universe should expand forever. So, for now, we're tossing out the easy to imagine scenario. "
rest at link
"There are three main flavors that scientists consider: positively curved, negatively curved, and flat. We know it exists in at least four dimensions, so any of the shapes we are about to describe are bordering on Lovecraftian madness geometry, so fire up your madness abacus. Ya! Ya! Cthulhu ftagen.
A positively curved universe would look somewhat like a four-dimensional sphere. This type of universe would be finite in space, but with no discernible edge. In fact, two distant particles travelling in two straight lines would actually intersect before ending up back where they started.
You can try this at home. Grab a balloon and draw a straight line with a sharpie. Your line eventually meets its starting point. A second line starting on the opposite side of the balloon will do the same thing, and it will cross your first line before meeting itself again.
This type of universe, conveniently easy to imagine in three dimensions, would only arise if the cosmos contained a certain, large amount of energy.
To be positively curved, or closed, the universe would first have to stop expanding – something that would only happen if the cosmos housed enough energy to give gravity the leading edge. Present cosmological observations suggest that the universe should expand forever. So, for now, we're tossing out the easy to imagine scenario. "
rest at link
