I've been asking my dad like 20 years---what's outside the universe?

Question

does anybody know?.....even a vague answer

man, exactly what I was thinking

my dad is engineer, but you made a point, the universe is highly likely a sphere

Answer 1

First you have to ask what you mean by "Universe".

What most people mean by this is the sphere, 13.7 billion lightyears in radius, that extends out to our "event horizon". If you look out that far, in any direction, what you see is the Big Bang. (Slight complication---the Universe did not become transparent until 400,000 years after the Big Bang, so what you actually see is the "surface of last scattering", the bright surface of the Cosmic Microwave Background Radiation.) We cannot see further than that---that is the limit of what we can currently know.

So what would happen if you went there instantaneously? Went in a wormhole, and came out 13.7 billion lightyears away? Well, it would look, on average, just like the galaxies near the Sun. That's because during that 13.7 billion years, all that material has evolved from the Big Bang, to look like the way things look in the solar vicinity---Big Bang material, aged by 13.7 billion years. And if you stood there and looked back at the Earth, what you would see is the material now making up the Earth, as it emerged from the Big Bang. If you looked in the opposite direction, away from the Earth, you'd see a lot of material that is currently beyond our event horizon, looking like a bunch of normal stars and galaxies. Our event horizon expands one light-day each day, so that "new" material is streaming across our event horizon. When we first see it, we see it participating in the Big Bang. We see the Big Bang retreating away from us at the speed of light, releasing more and more material into our "Universe".

So the Universe is bigger than the sphere of material we can see within our event horizon. How much bigger? The answer seems to be "a whole heck of a lot bigger", based on the well-accepted (but not fully proven) theory of early inflation---about 10^50 times bigger in volume, give or take a few factors of a trillion. If you were able to move infinitely fast within that volume, you'd find it all looked a lot like the galaxies in the vicinity of the sun---similar density, similar material, similar physics.

What lies beyond that stupendous volume? It's thought that at distances of approximately 10^30 lightyears, the laws of physics may be different ("the Higgs boson fell into a different energy state" are the words that go with this). So there may be a lot more stuff out there, but it acts differently than our part of the Universe, because particle physics is different. What this means, exactly, no one knows yet, but if we ever achieve a unifed theory of physics the answer may be more clear.

Answer 2

When I was 7 I was talking to my dad about the universe, well actually about space and me never having encountered anything that was not finite, I was asking him where space ended. After trying to explain it to me unsuccessfully for some time he finally said, "Ok, imagine at the end of space and there is a brick wall" "Ok" I said, then he said, "Ok, now, what is on the other side of that wall?" And for the first time it hit me that space just goes on and on. Since then I have read much about the Universe and have come to a different understanding about it. And it is this: the Universe is 'everything that is', it is expanding outward from the point of the big bang at the speed of light - so the 'edge' of the universe is actually the light wave that has progressed the farthest outward - that is where the universe ends. What is beyond that is impossible to know because of the fact that light is the fastest thing there is and nothing can "outrun" it. Therefore, if there is something out there beyond the edge for us to detect, there is no way any signal or anything can go faster than the light that is the expanding edge of the universe to bounce off of it and back to us. So we simply CANNOT know if something is beyond the universe. We can speculate until the cows come home but we cannot know.

Answer 3

Well, the thing about a "universe" is that it is everything. For something to be outside the universe, we can have no way of experiencing it.

There are theories of other dimensions, and while we think this may be 'another universe', for us to detect them means they're part of *our* universe - even though we're unable to experience them.

I think there's probably other universes that exist. I can't prove it; wouldn't even want to try, but... that's my feeling. Universes where the speed of light is different than ours, where the gravitational constant is meaningless, and where the forces that formed matter into atoms in this universe weren't strong enough to do the same in another.

I can't prove that belief to be right, but likewise, no one can prove it to be wrong, either.

Answer 4

Your dad is not alone. Einstein once said that other universes were possible to exist and they could have different physical laws than ours does. It would be possible for a universe to exist where everything moved at faster than light speeds and they could go no slower. Such fast moving particles are called, tachyons, and science has attempted to detect them at the fringes of our universe, without success. In theory there could be billions of universes and all of them would have the same problem we do in trying to understand what lies outside their borders. To me, the void that contains these universes is never ending, of course it can't be called a void because of all the matter within it, but we are dealing with what is outside of all this matter and I know of no word to describe it. It seems that this information is forever beyond our knowing.

Answer 5

Some theorize that there is nothing 'outside' the universe. If ever there is an outside. Think of it like the Earth. Where is the end of the Earth? It's hard to say because it's a sphere, if you try to drive a car in a straight line across the surface, you'd be back to where you started after some time. No one can really say if it's correct. If you're dad is a physicist, he may be able to tell you some theories. :D

Answer 6

Take a good telescope. Look to your left and then look to your right...... a bunch of stars and galaxies in both directions.

Now think of an astronomer on a planet 13 billion light years away on your left side. He looks to his right and see's a bunch of stars and galaxies. Way way distant he see's our galaxy (as it looked like long ago, of course.)

Now he looks to his left. Does he see just BLACK? No. He sees a bunch of stars and galaxies up to 13 billion light years away.

The universe goes on forever. Matter and space started at the big bang. Matter isn't enclosed in a sphere and didn't expand like a balloon into the blackness of space. Matter appeared EVERYWHERE.

Answer 7

I am not surprised your Dad has failed to tell you the answer after 20 years, because nobody knows. I have read many therories on the subject from the crackpot to the elegant, and I am still no closer to finding any answer in my head. I can accept the broad argument that there are other universes, with which we probably interact, just as I can that there is nothing outside of this universe (both zero and infinity are hard to grasp for most). Lets find out what is inside first.

Answer 8

As far as we know, NOTHING

OUR universe starts with BCR or Background Comsmic Radiation or Gamma Rays

It infects NOTHING with this radiation

So you have this boundary

A little light and CBR on one side and NOTHING on the other side

Light and CBR push into the NOTHING infecting it with SOMETHING

On the OTHER SIDE, far away from CBR and LIGHT there is NOTHING, DARK

WE INFECT that with the PUSH of OUR UNIVERSE

BIG BANG continues

Until it stops (maybe)

CBR moves at the speed of light or near it

It stops ONLY when a gravity well pulls it back and halt it

NO ONE has found THAT event YET

So it still moves at or near Light Speed

So that is your THEORETICAL answer (no one is actually OUT THERE to verify it)

Answer 9

The universe is comprised of everything there is. So there is no such thing as "outside the universe"

Answer 10

Yes it is big. So big that it could take u 100,000 years to get there at the speed of light.