If outer space is always growing, where is it growing into?

Answer 1

Space in infinite. Its growing into nothing and filling it with space. The universe has no boundries, which is hard for the human mind to fathom, no Im not taking a hit at you. Astrophysics requries a certain mindset, to literally be able to think beyond boundries. The universe is accelerating outwards into nothing and filling that nothing with space. To comprehend "nothing" is not easy. It is if you are counting apples and you have none. But to actually say nothing exists in a location binds science to philosophy.

Answer 2

Easy answer: we don't know.

More detailed answer: it appears more and more likely that the universe is infinite in size. The recent data from the WMAP space observatory has ruled out much (but not all) of the possibilities that the universe has a finite size; it has certainly ruled out all theories that gave the universe a "small" size (whatever that means).

If the universe really is infinite, then it is simply growing "into" itself. Difficult to imagine, so I'll use a number analogy:

Take the set of all integers { ... -3, -2, -1, 0, 1, 2, 3... }; imagine that the numbers stand in for galaxies with intelligent beings. The ones in galaxy "2" see themselves at a distance of 1 from the beings in galaxy "3".

Let us expand that universe by multiplying all the numbers by 2. The new set is {... -6, -4, -2, 0, 2, 4, 6...}. Our observers are now at 4 and their neighbours are at 6, a distance of 2 (the relative size of the universe has doubled).

Has it grown into anything? No. Take whatever number you can imagine, then multiply it by 2; that number was already part of the original (pre-expansion) set.

1,783, 912,603 becomes 3,567,825,206 which was a number in the original set (before doubling). So galaxy 1,783,912,603 did not get pushed into a part of "space" that did not exist before the doubling.

Another theory is that the universe we know is a 3-dimensional subspace of a space with more than three dimensions. And the 3-D universe is wrapped around a fourth dimension. Of course, this raises the question: what is this 4-D universe like. Those who have tried to answer this question are now up to 10 or 12 dimensions, in order to explain everything we observe.

An easier analogy is the 2-D surface of a sphere which is wrapped around a third dimension. If you can imagine 2-D beings living on (or "in") the surface of a sphere that is expanding, they will see their universe expand, without appearing to expand into anything. That is because they cannot perceive the third dimension into which their sphere is expanding.

If our universe really is a 3-D space wrapped around a fourth (or twelve) dimensions, we would ask ourselves the same question, as we cannot perceive this fourth dimension.

Answer 3

Well it's not necessarily that outer space is growing, but it's that everything is getting further apart. Space, by definition, is infinite and therefore can't grow

Answer 4

It isn't growing into anywhere. It is simply expanding. Space and Time are expanding. There isn't anything "outside" outer space for it to be expanding into, since there is no outside of outer space.

Answer 5

It is growing from within relative to us and our measuring sticks. That is equivalent to saying we and our measuring sticks are shrinking relative to space. If you believe the BigBangers, the universe is getting bigger, but gravity makes it bend back on itself. If you believe the universe is infinite, then it's size can't get any bigger; but we still measure increasing distance to any very distant galaxy. Either way, space has no center and no boundaries.

Answer 6

nothing