What is a "flat" universe?
Hi
I read about the different shapes that are postulated for the shape of the universe. But what is meant by a "flat" universe? Is it the shape of a sheet, or blanket? If it is, why would the universe expand in suck a manner? It doesn't seem to make sense that it...
If the universe began from the Big Bang, then why is the universe not a spherical shape? I mean, if it expanded from a singularity, then why is it not spherical?
Why are all stars not the same size? Given that the nuclear fusion within a star begins when the pressure/temperature in the core of a collapsing cloud reaches certain parameters, why are all stars not the same size?
Hi. I am confused about plate boundaries. In school we always drew diagrams where the continental crust sat on top of the oceanic crust. With that in mind, what is a collision boundary? Is this where continental crust sits on top of the mantle? How did India collide with Asia? Is the Indian...