New answers tagged

3

The simplest answer is that Milne's explanation requires a non-uniform cosmos, with a formerly crowded "starting area" that expands into empty space. Observations indicate that the cosmos is nearly uniform at very large scales. With Milne's model of a non-expanding space and uniform cosmos, galaxies that started near to us with high velocities that ended ...


2

There are no such theories because there is an immediate problem with both scenarios as stated. It is a fact that a spherical shell of material has no net gravitational influence on material anywhere inside it. https://en.wikipedia.org/wiki/Shell_theorem


-1

(My answer here isn't correct, as pointed out by the first comment on this post, please refer to it.) Yes, it certainly is possible - and it already has happened. The age of the universe is 13.8 billion years, yet it is something like 90 to 100 billion light-years in diameter. This means that we definitely can't see all of it, not because of our own ...


7

Expansion depends on the amount of mass Yes, space expands more in regions with less matter — in fact this has been proposed as an alternative explanation to dark energy as the cause of the observed accelerated expansion: If by chance we happen to be located near the center of a "cosmic void", then nearby space expands faster than distant space, and since ...


Top 50 recent answers are included