Could it be somehow proven, at least theoretically, that space is infinite?

Question

tropicvibe : "...Don't know if the universe is but space is infinite. Universe expands. "
Can I have 1 more question?
Could it be somehow proven, at least theoretically, that space is infinite?

Answer 1

Actually, before Hubble discovered that the Universe is expanding, physicists including Einstein thought the Universe was infinite and static (this point however was still based on assumptions, not proven by observation or theory). But now that we know the universe was created via the Big Bang, and has been expanding ever since implies that the Universe is "finite", albeit very very large (estimated to be at least 15 billion light-years in diameter).

Answer 2

The Universe we live in is most likely finite in size, but unbounded....i.e: It has no boundaries. Think of it being like a sphere. A sphere has a finite shape and size, but to everything on the surface of that sphere, there are no boundaries in any direction (except of course in the up direction, since the surface of a sphere is a 2D object). Now project that sphere into 4D (3 dimensions of space and 1 of time). That gives you what we observe as the Universe. No boundaries in any direction, including up.

However, there is a boundary of sorts which is defined by the speed of light barrier and is called the horizon distance. This horizon distance encompasses what we know of the Universe, otherwise known as the Observable Universe. It is about 30 billion light years wide (physics_dude, you only gave its radius, remember it's 15 billion light years to the horizon in every direction). The horizon distance is the distance at which an object will recede from us at the speed of light.

However the total Universe......or megaverse if you like, is much, much, much larger. Given that during Inflation, the Universe expanded from an object 10^33 times smaller than a proton to something like 100 million light years across in 10^-37 seconds, and that edge of expansion kept on going at nearly that rate afterwards, the megaverse is trillions of trillions times larger than the Observable Universe that we see.

That would account for the geometry of the present Universe..... being close to flat right across its entire width.

Answer 3

I appreciate yur understanding Mr..


I say that there is an end to the universe not only but also to space

Answer 4

We couldnt find any brickwall as far as we look in the space. We have looked up to 15 billion light years. Is this enough as proof

Answer 5

Well it isnt proved that space and universe is finite so it is naturally infinite.

Answer 6

I always wonder that myself. Since space is nothing at all im guessing it's infinent.