# If a blackhole contains a singularity, and the big bang was as well

1. Jun 27, 2008

### 4ton Mantis

Is it dumb of me to think that a blackhole just becomes so massive at some point, it basically tears a hole thru the singularity and explodes outwardly like a big bang (through spacetime into another universe or something), or a pin finally pushed thru an extremely tight baloon?
just curious what you guys thought, i have a psych degree and physics has always been an interest.

2. Jun 27, 2008

### Xezlec

What force would push it outward exactly? Gravity attracts. Strong force attracts. E-mag probably doesn't do anything here. Why would it want to explode when it's got all it wants right there in its introspective self?

3. Jun 27, 2008

### 4ton Mantis

the big bang exploded from a singularity...am i wrong?

4. Jun 27, 2008

### muser

I agree xezlec. But another way of looking at it (at least I hope it's another way) is that what force is acting on the singularity for it to create the big bang. with the current theory being the initial big bang singularity had reached a a point of infinite density and ran out of options. Though according to georg cantor, infinity really means just that, infinity. There would be no big bang if the singularity was infinite. I'm assuming since I acquired this knowledge, the powers that be have revised their view on an 'infinite' singularity. which still leaves xezlec's original question.

5. Jun 27, 2008

### 4ton Mantis

No, it's a fine question, you're right. But i thought the big bang exploding from a singularity was fairly agreed upon.

Edit: this is kind of how i imagine it going down though: the black hole stretches spacetime like in that video w/ a bowling ball resting on a trampoline, and it becomes so heavy, and concentrated to a point, that it punctures the fabric of spacetime and everything that was being held into that one point by gravity, would come rushing out the other side in a big bang when it punctures. mebbe?

Last edited: Jun 27, 2008
6. Jun 27, 2008

### Fredrik

Staff Emeritus
That's not at all what the theory says.

7. Jun 27, 2008

### Xezlec

I don't know the explanation for the big bang. I leave it to someone else to explain. But I think it's complicated.

I think you're taking the "stretching fabric" analogy a bit far. I don't think it's an actual membrane separating two places. And the bowling ball itself is what's generating the gravity. It sucks itself into itself, not sucked into some other place by some external force and held back by some spacetime membrane. I think the stretchy fabric analogy, which is meant to help us lesser mortals understand a complicated theory of gravity's effect on the topology of the universe, is just trying to show that the topology of space changes, much like how if you stretch a piece of fabric in the middle, then there is "more space" in the middle than there would be if the fabric were flat.

8. Jun 27, 2008

### cristo

Staff Emeritus
The Big Bang Theory does not tell us what happened at t=0: this would be equivalent to us knowing how the universe "came to be." All the theory says is that there was a time in the universe's history where it was a lot denser and a lot smaller than it is today. The universe has since "expanded" from such a state.

9. Jun 28, 2008

### Blueprint

Blackholes are content to continue gobbling up matter, how do u get more massive than infinity?

It seems like you're wondering what started the big bang, and putting it down to a hole rippage of the singularity (whatever that means). Not sure how you can tear a hole in a point of zero volume.

If you extrapolate the properties of the universe to the instant of the Big Bang, you will find that both the density and the temperature go to infinity (or close to it with a quantum theory of gravity). What started it was the expansion of spacetime along with this primeval fireball. Right? :)

So I wouldnt say "the big bang exploded from a singularity..." Id say that almost zero volume almost infinitely hot and dense ball just got taken along for the ride in all directions.

10. Jun 28, 2008

### Troponin

Could the energy potential reach a high enough piont, nearly infinite, that necessitated new matter?

Sort of the "ran out of options" idea, where the only option was to release its energy as new matter at a magnitude higher than the forces that would pull the matter/energy together?

11. Jun 28, 2008

### Xezlec

I don't understand this whole idea of "options". Why does a black hole need "options"? Why can't it just be content to be a black hole?

12. Jun 28, 2008

### yuiop

Hi,

I have attached a graph plotting the Newtonian gravitational potential versus the Schwarzchild gravitational potential. A singularity has all the mass concentrated at a point so I have used the exterior Schwarzschild solution for coordinate gravitational acceleration $$\frac{GM}{R^2}\left(1-\frac{2GM}{Rc^2}\right)$$ and integrated it to obtain the Schwarzschild coordinate potential $$\left(\frac{GM}{Rc}\right)^2- \frac{GM}{R }$$

The plot of potential is useful because it is easy to visualise how an object moves in the gravitational field simply by imaging how a ball placed on the slope would roll. The Newtonian potential indicates that an object would simply fall down an infinite hole while the Schwarzschild potential indicates that matter gravitates towards the potential low point at the Schwarzschild radius suggesting a black hole could well be a hollow shell of material located asymptotically close to the event horizon. Now if you picture a point particle very close to R=0 in the Schwarzchild potential it is at the top of a potential mountain that goes towards infinity as R approaches zero and it would accelerate outwards with extreme acceleration and velocity. If the initial conditions of the universe started as a region of extreme density this model suggests that it would inflate very rapidly. This model also suggests that singularities are extremely unstable and would not exist for more than the briefest possible time. This is not my personal theory. It is simply the maths of the GR and Schwarzschild. I do not know the mechanism for repulsive gravity suggested by the math.

#### Attached Files:

• ###### potential.gif
File size:
16.6 KB
Views:
55
13. Jun 28, 2008

### Troponin

"Options" wasn't my term. I asked if there could be an energy potential in a singularity that would necessitate new matter?
Somewhat along the lines of the Schwarzschild potential in a singularity.

It doesn't need options, it can be perfectly content being a black hole, but what is that black hole "doing" while being content to be itself?

14. Jun 28, 2008

### Xezlec

Nuthin. Watchin the game. Drinkin a bud.

15. Jun 28, 2008

### Troponin

Blackholes, they're so much like us...

16. Sep 10, 2008

### scottam

Wow, I actually woke up tonight with an idea about black holes and their use in the creation of a big bang. I typed up my ideas very quickly and then hoped online here to see if anything had been thought of that was close to my idea, and I found this thread, which is about as close as it comes. Briefly, here are the ideas I came up with tonight, please let me know what you thin but keep in mind that it was typed up in a hurry to just get the ideas out before I forgot them, I will expand on them later.

Points on Singularity Theory:
• When a black hole is created, it creates its own singularity, with its own mass of the star that it once comprised.
• This mass would be the mass used to punch a whole in the fabric of space (create its own dimension) and start its own big bang.
o It is thought that 98% of everything that exists was created in the first hour of the big bang singularity. The Black hole existing in the previous universe (presumably a larger universe), and attracting and sucking in matter continuously would explain the other 2% that was not created in the moment of creation.
• Scientists at the current moment cannot explain all occurrences in space as there appears to be “extra” gravity that could only be explained by the existence of large quantities of dark matter (that we have not yet been able to find). Could these unexplained gravitational forces not be explained by the gravity of the “original universe” that the black hole was formed in exerting force into our universe?
• This theory does not explain the how/why of the single original universe being created, but it could explain the creation of countless other ones. The original universe could have millions of black holes created, each one creating a singularity and its own dimension and universe. Each of these subsequent universes could have millions of their own black holes, and so forth. Each singularity would have its own chemical makeup when created (depending on the makeup of the star it once was), therefore would have completely different physics and matter. Gravity would be one constant found throughout, that is why we can understand nuclear and electrostatic forces (they are particular to our universe); while we cannot explain everything about gravity in a macro scale since it is tied from universe to universe.
• This theory explains why there is no “space” before the big bang, yet where the matter and energy that created it came from.

Thanks.

Last edited: Sep 11, 2008