Could the big bang have been caused by a black hole?

[Hypercube]

When I was doing some research, I found a theory that the universe which we know is actually only the surface of the entire universe as a hypersphere. Something then occured to me; if the universe really is a hypersphere, what keeps it from collapsing? I think it is pretty safe to assume that the universe does not have a solid shell surrounding it that allows it to keep is't form. I came up with two possible explanations, maybe both of them are correct.

 

1) The interior of the universe contains massive volumes of negative energy. This could theoretically explain why the universe isn't collapsing because since negative energy is repelled by gravity as opposed to attracted by it, it theoretically could hold the universe it it's hypersphere form.

 

2) The second possibility which I came up with is that the hypersphere is kind of like a balloon; meaning that the interior of the universe contains astronomical amounts of gases such as hydrogen, nitrogen, etc. I suppose that if there were enough pressure being exerted by all of the gases, the hypersphere could theoretically be kept from collapsing.

 

Now for the more confusing part. Scientists think that at one point, all the mass of the visible universe was at one point (forgive the pun) a single point, or a singularity, or a black hole. Naturally the gravity of such a dense black hole would be huge and would cause tremendous strain of the hypersphere's surface (Einstein sais that massive objects make dents in the fabric of space-time). Now, what would happen if at one point, the singularity actually made a puncture on the surface of the hypersphere and linked the surface with the interior? The same thing that would happen if you stick a pin into a balloon; the interior contents leave through the hole.

 

Since it is believed that at time zero, the universe expanded faster than the speed of light, the matter inside the hypersphere would be able to escape the black hole, and possibly make up our visible universe. And of course, if there was negative energy inside the hypersphere, it would have no problem leaving the black hole because gravity repells it, which could theoretically explain inflation.

[Klaynos]

1) What is "negative energy", and why is it repelled by gravity?

 

2) But we know that large areas of space are pretty much empty...

 

I'm pretty sure that talking of the universe as having a surface is pretty much un-physical, so there couldn't be a puncture...

[jbahr]

As I remember, the surface of a 4-dimensional hypersphere is a 3-dimensional sphere (a 3-ball). However, if I'm reading all those noted cosmologists correctly, the universe isn't anything like a sphere. It has neither a center nor an edge, and (as Wright likes to point out repeatedly) it doesn't expand into anything.

 

Regards,

J

[Xyph]

I think you're taking the analogy a bit too far.

 

The surface of a 4D hypersphere is a 3D surface, not a sphere. That is, if you go far enough in any direction in our 3-dimensional universe, in this scenario, you will circumnavigate the hypersphere and end up back where you started.

 

Because of this, the (hyper)volume contained by the hypersphere will also be 4-dimensional, not 3-dimensional, as in a normal sphere. So it doesn't make much sense to try to think of what stops the hypersphere collapsing, because whatever forces are involved can only ever be explained by physical laws that go beyond our universe.

 

It can't just be assumed that gases (or dark energy, even, as we perceive it) could exist and behave in a way that we are used to within a hypersphere, because they will have to exist in a 4D space - meaning the physical laws governing them could be very different.

 

 

Remember, this idea is just a way to visualize a possible shape of the universe. It says nothing about WHAT makes it that shape, anymore than we can infer any characteristics about the Earth's interior from only the fact that it is a globe.

[Martin]

As I remember, the surface of a 4-dimensional hypersphere is a 3-dimensional sphere (a 3-ball). However, if I'm reading all those noted cosmologists correctly, the universe isn't anything like a sphere. It has neither a center nor an edge, and (as Wright likes to point out repeatedly) it doesn't expand into anything.

 

Regards,

J

 

the surface of a 4D ball is called S³. it is not a 3-ball.

it has no centerpoint in it, or edge. all points in it are equally "central" or equally non-central.

 

for instance the surface of the solid ball {w^2 + x^2 + y^2 + z^2 <= 1}

is {w^2 + x^2 + y^2 + z^2 = 1}

and that is a 3D thing, an example of S³, with no central point in it and no edge

 

people get confused with the words "sphere" and "ball"----the solid ball and its sphere surface---we even get confused talking in lower dimensions already and it is a bit worse in higher

 

You say " the universe isn't anything like a sphere." but I think you mean " the universe isn't anything like a BALL."

 

AFAIK space could topologically (just considering space itself not embedded in some Euclidean space of higher dimension) be equivalent to S³

this is a possibility that mainstream cosmologists take seriously---consider as a case when analyzing data. The other main contender is simple flat infinite.

 

You have heard of the simple DE SITTER model universe. The spatial slices of dS universe are S³ ---- often called 3-sphere. In the research I follow,

De Sitter universe is getting increasing attention these days because it is the simplest solution to einst. eqn. which has a positive cosmo constant. It is not bumpy like the real universe but it is a good largescale model.