If the Big expansion expanded from an infinitely small dot of mass, what did it expand into...?

Question

let me quote Jose Frink from one of my last Q&A`s, I LOVE THIS

"It's as if the universe were a giant raisin bread, rising in the oven. As the bread rises (as space expands), the raisins (galaxies) don't actually pass through the bread, making tunnels as they go. They are carried along by the expanding bread between them, remaining more or less stationary all the time, and yet expanding away from each other. The farther two raisins are apart, the more bread there is between them, and so the more rising there is expanding them apart. The only difference is that the raisin bread has edges, but the universe has no edge."

My query is.... theres got to be an edge, an outside edge to the expansion? and what`s the outside edge moving into? ...its the same question, whats at the end of space? a brick wall? (just a little joke)

Answer 1

Physics is so crazy isn't it. They say and who am i to disagree that both time and space came into existence at the moment of the big bang. So everything appeared from nowhere and expanded into nowhere. Creating somewhere which we call our universe. If that is difficult to imagine they say most of it ie Dark Matter is invisible and cannot be detected, because it's in a different dimension. They say all that because the maths seems to suggest it. Personally i don't think anyone will ever know for sure. But it is fascinating stuff nonetheless.

Answer 2

I do not think there is any edge to  the universe.It is incomprehensibly vast with no end at all,none what so ever.the matter that is within this space is all that the universe has and will ever have,the sole purpose for this supposed empty space is too recycle everything over and over again for eternity,so that life can have chance and that is the real mystery in my opinion.

Answer 3

Imagine a 2D universe on a sheet of rubber, if you expand that 2D universe then yes the edges expand into the plane. Now roll the sheet into a balloon and imagine a 2D universe on it's surface, in our 3D world the balloon expands into a greater volume but the volume isn't our 2D universe just it's surface which has no edge but still grows larger.

Whether the universe is infinite or finite in extent is irrelevent to the fact that there is no edge, the earths surface is finite in extent but if you start walking (carefully pa.cking a boat) you can walk for ever but still there is no boundary after which you are no longer walking on the earth

Answer 4

The singularity that is thought to have given rise to the Universe as we experience it today, WAS the Universe.

Answer 5

There's nothing outside the universe, the universe is everything.  The universe is the shape of a topological 3-sphere, so that it is technically expanding into itself - its not expanding in the perceptual mislead that it has to be expanding into some type of external substance.

Answer 6

The universe wasn't "expanding into" anything.  You have to think a little bit deeper.

All of space--everything, the entire universe expanded.  There, in this theory--isn't anything really "outside it" for it to expand into, since it was all of space itself.

Answer 7

The Big Bang  most likely was never an "infinitely small dot of mass".  The Big Bang may have been extremely large, or perhaps even infinite in extent, for all times after time zero.  Time zero itself (an infinitely dense state) most likely never existed, because quantum mechanical processes that we don't understand very well would prevent such an infinite density from occurring.  The infinity at time zero is an artifact of the classical nature of the equations of general relativity and does not reflect reality.

Answer 8

Here it is in easy terms. When you think of 'space' think of the dark void of nothing that everything is floating in. Think of 'universe' as everything that has mass. Stars, planets, dust, ice, metal. The big bang theroy is where this tiny point in space had so much mass that it kept collapsing on itself till it build so much pressure that it exploded. Everything you see today was that mass. Beyond the furthest mass in space is more space. Its hard to comprehend. The mass has never changed and will never change. Eventually, the universe will colapse again and another pulse in time will begin. In theroy.

Answer 9

A big knife to slice the bread?

Answer 10

Glad I could help :)

General Relativity, our theory of gravity, is one of our most tested, and most accurate theories in all of physics. It is fundamentally a theory of geometry, and it has a lot to say about the possible geometries of the universe. But it forbids the universe from having an edge. There is no end of space; no brick wall. GR forbids this.

Basically, it says you can't fall off the universe in exactly the same way that Columbus could never have fallen off the Earth. The universe might be infinite in size (so no edge) or it might be finite. If the universe is infinitely large and you rocketed off in a straight line, then you could go forever and never stop passing stars and galaxies because the universe is uniformly filled with them. If the universe is finite, then if you rocketed off in a straight line, you would still never stop passing stars and galaxies, because you would eventually return to your starting point.* If GR is correct, then this must be so.

Actually, this edgeless property is a requirement of any metric ("geometric") theory of gravity, not just GR. And you can prove that as long as gravitational mass an inertial mass are equal, the correct theory of gravity is a metric one. I find that really cool--- that you can prove using logic alone some amazing things about the universe only by observing that gravitational mass and inertial mass are equal. This is why science is so much fun. It has been experimentally shown that the two definitions of mass are equal to at least one part in a trillion.

Anyway, there is no "outside" the expansion. All points of space and time are within the universe, and the universe (all points of space and time) is uniformly filled with matter everywhere. There is no point of space outside the universe. The universe expands only in the sense that the distances between all these points of space are constantly increasing.

And finally, don't put much stock in this "infinitely small dot" business. GR is the most correct theory science has ever produced (it makes the most accurate predictions of any theory ever tested), but we still know it is wrong**, because it is not a quantum theory. Therefore, regardless of how incredibly accurate it is for large things like stars, galaxies, and the universe, it cannot be applied to extremely tiny objects, like the universe before it was about 10^-35 seconds old. Before that time, the universe (i.e. absolutely all of space and time) was too small (or, in the case of an infinitely large universe, too dense) to be described by GR.

In order to talk about it scientifically, we would need a quantum theory of gravity, which we do not have yet, because it would have to be both metric and quantum, and those concepts don't tend to play nice together for various technical reasons. This business of "infinitely small" anything isn't scientific, because it comes from applying a theory that we know is incorrect in that regime.

*Actually, the universe is expanding too quickly for circumnavigation to ever be possible, even in principle, but hopefully you get the idea.

**GR must be a logical deduction of the correct quantum theory of gravity because it is so incredibly right when discussing macroscopic phenomena. This is how science usually works. Newton's Theory of Gravity is fantastically correct at low energies, but it is not applicable to high energies like around black holes or neutron stars. GR, which is correct at all energies, becomes Newton's Theory of Gravity when you insist that the energies involved must be low.

Answer 11

Is their an edge or not?

If not, why not ?, if their is,why?

Did space expand into something that was their,or did it not expand into something that wasn't their.

Is space the equivalent of a Mobeus strip? or is it a continuous ribbon,or what.?

No-one can give you a truthful,finite answer,why? Because no-one knows.!!

It's all theoretical.

Answer 12

If you start to think multi-dimensionally, you are able to realise that it is perfectly possible for it to be 'expanding' into itself.

Think of how a finite triangle can contain an infinite number of replicas of itself - do a web search for 'Sierpinski Gasket'.

Answer 13

The universe is not infinite, therefore it does have an "edge" of sorts, but not one that is ever reachable.

Space and time are warped which means that no matter how fast or far you traveled, you would always end up back where you started,

As far as what it's expanding into - it's actually creating it's own space as it goes, so it's not actually expanding "into" anything. If there's actually anything worth mentioning outside of our universe, nobody has the vaguest idea what.

I've seen a few of your qs tonight - a really great book on all this stuff is A Brief History of Nearly Everything by Bill Bryson. Loads of great stuff like the analogy you mentioned above -  highly readable and easy to understand.

Answer 14

A very simple question, but science unfortunately has no clear answer.