Questions on Big Bang Singularity

[PhysicsDad]

I have a question that is probably un answerable. At the exact moment the Big Bang was sent into Motion, it is assumed that all the mass-energy was condensed into a very powerful singularity. At that moment, the mass and gravity should have been so instance that an explosion would be impossible. First off, how could an explosion exceed the speed of light so it could escape the event horizon. Secondly, and I am sure that our current theories can't explain this one, Where could all that mass energy come from, and why would it suddenly blow up? Unfortunately our equations break down at a singularity. And on the note of singularities, if the escape velocity is "c", how could any particle even get close enough to reach the EH so that it could split and cause Hawkins radiation? Wouldn't the particle have to be traveling just over c to even get there? I am truly interested in learning how this world works, but there are still a lot of things I Don't understand.

Any incite or discussion would be great!
Thanks all for your knowledge.

 

[jedishrfu]

For starters wikipedia has an articles explains some of this stuff:

http://en.wikipedia.org/wiki/Big_bang

The key point of the big bang is that space and time were created at the big bang moment of creation, so we can't talk about anything before the event. The second point is that space can expand faster that particles can move so there's no limiting speed such as light speed. The third point is that the moment the big bang occurred there was energy but no particles until spacetime expanded and thing cooled sufficiently for them to form.

Right now the big bang explains a lot of the observations that we can measure with today's instruments and so it is accepted as the proper explanation of the formation of the universe.

Beyond that there are alternative speculative theories that come out of the math that haven't been proven or disproven sufficiently to replace or extend the Big Bang and so it remains.

Also it seems you are conflating Black Holes with the Big Bang singularity which I don't think is right. The creation mechanism for a black hole is different from the big bang.

 

[PhysicsDad]

So if I am understanding you correctly, we don't currently have any theories as to where the energy or cause of the Big Bang came from? I suspect that is the case, I just know that there are a lot of people out there that are more knowledgeable on this topic than I am, so I am kinda grasping for straws. Also, the part about the black holes at the end we intended to be a separate thought. I am sorry if that sounded misleading. Thank you for your input.

 

[jedishrfu]

String theory talks about branes bumping together and creating a big bang universe but like I said it speculative coming out of interpretations of string theory models.

http://en.wikipedia.org/wiki/Brane_cosmology

and the Big Bounce:

http://en.wikipedia.org/wiki/Big_Bounce

Both of these are very speculative theories neither proven nor disprove by existing observations.

 

[Bandersnatch]

Big Bang is a derisive name that Fred Hoyle gave to the theory he didn't agree with. It unfortunately stuck, producing a never ending flow of people taking the name at a face value.

In actuality, BB is a theory stating roughly that the distances between objects in space are expanding and that the universe used to be much denser and hotter in the past.
It does not say anything about the t=0, or the origin of the universe. That we get a singularity(as mentioned by jedishrfu, not the same as black hole singularity) when we try to extrapolate the theory to t=0 is an indication of its limits, not a description of the physical state of the universe at that point in time.

One of the other misconceptions brought about by the "Bang" in the theory's name, is that it describes an actual explosion in a pre-existing space. There was no explosion, just increase in distance between objects. All the mass and space had already been there, just much closer to each other.
This is rather important to understand the "why" of faster than c expansion. General Relativity does not allow objects to move faster than c THROUGH space, but has no qualms with the space itself expanding.


As for the theories that try to explain the origin - in some sense at least - there are the cyclic models, but jedishrfu has already managed to mention some of them, together with the necassary disclaimer regarding their still speculative nature.


Regarding the Hawking radiation question, I believe the simplified idea is for a particle-antiparticle pair to pop up from vacuum fluctuations just around the even horizon, so that one of them gets sucked into the black hole, while the other one escapes. There are no particles escaping from beyond the event horizon itself.

 

[Chronos]

The big bang theory does not extend back to t=0. At best, it is only good back to the first tick of Planck time [~E-43 sec]. Some believe it is only good back to about the time that inflation ended [~E-30 sec], which is logical given BBT offers no explanation for the inflationary epoch.