Universe Expansion: What Force Triggered the Big Bang?

[filegraphy]

What I was thinking is that we know if the Big Bang occurred that it explains why we think the universe is expanding. I thought about what force triggered the singularity to expand into space itself. Using Newtons First Law of Motion, that a body remains at rest or travels in a straight line unless acted on by another force. Can somebody explain what force acted upon our universe, 13.7 billion years ago?

 

[bapowell]

Modern cosmology does not address the initial singularity or the dynamics of the big bang itself. General relativity is believed to break down at the initial singularity, and so cosmologists need a more complete theory of quantum gravity to address this critical time. Despite recent progress, we still don't have one.

 

[Fredrik]

What I was thinking is that we know if the Big Bang occurred that it explains why we think the universe is expanding. I thought about what force triggered the singularity to expand into space itself. Using Newtons First Law of Motion, that a body remains at rest or travels in a straight line unless acted on by another force. Can somebody explain what force acted upon our universe, 13.7 billion years ago?

The big bang was not an explosion, and the singularity is not a point in spacetime. The big bang is a mathematical property of a class of solutions of Einstein's equation, which describes the relationship between how things are distributed in the universe and how those things move. The original big bang theory is the claim that the universe is described by one of those solutions. Since then, other big bang theories have been developed. Some of them have even disposed of the initial singularity and describe the big bang as a phase transition that occurred after an initial period of rapid inflation.

Your question doesn't really make sense in the context of the original BBT, but it does seem to make sense in the context of inflation theories. I don't know them well enough to give you a really good answer. They all involve matter of a type that's never been observed, and phrases like "decay of false vacuum", which are very hard to understand (even for us physics nerds).

I will also quote myself:

I suggest that you follow diogenesNY's instructions here on how to get free access to a good article about the big bang.

The big bang was not an explosion somewhere in space. I know that's what the name suggests, but it's more wrong than thinking that there's buffalo meat in Buffalo wings. These two posts might make things a little bit clearer: 1, 2. The http://www.scientificamerican.com/article.cfm?id=misconceptions-about-the-2005-03 that was mentioned earlier in this thread is even better, but it looks like you will have to pay for it.

(The article I mentioned is the same one that diogenesNY is talking about. If you follow his instructions, you can read it for free).

 

[TimBowe]

No physicist holds that the singularity actually exists it's just an ideal mathematical limit to a series in a sense of calculus.

Stephen Hawking's quantum cosmology uses "imaginary time" as more fundamental than "real time". The principle of causality only makes sense in real time where there are light cones at each spacetime point event. It is violated in imaginary time. The missing mass enigma may be a clue that real time is only the top of an iceberg. Most of the universe may still exist in imaginary time. Mathematically spacetime is described by a metric tensor which has a topological property called the "signature". The light cone only exists in real time where the signature is -+++. There is no light cone in imaginary time where the signature is ++++. The phase transition from imaginary to real time which starts the Big Bang is a topological transition. Is it controllable from the far future of real time in a self-consistent loop?

 

[TimBowe]

Thus, the big bang can be seen as the beginning of bubble nucleation, and the spontaneous nucleation of universes.

 

[nickdk]

Thus, the big bang can be seen as the beginning of bubble nucleation, and the spontaneous nucleation of universes.

Completely curious. Would this suggest that essentially our universe is spawned from other universes? Or say, our universe was born from the energy&mass of another...and it then adjoined the others?

 

[Chronos]

Completely curious. Would this suggest that essentially our universe is spawned from other universes? Or say, our universe was born from the energy&mass of another...and it then adjoined the others?

That is unknown and probably unknowable. It is conceivable the big bang created time, hence, the age of our universe is indeterminate.

 

[TimBowe]

What exactly is a topological transition and does anyone think it could have started the Big Bang?

However, if we invoke quantum mechanics, as Hawking and James Harte have done, the Heisenberg uncertainty principle requires the light cone, instead of coming to a point, to be rounded into something like a hemispheric cap. The radius of the cap is the Planck length, which is very small, about 4 X 10~33 centimeters. This cap forms during the Planck time from the beginning of the universe, which is about 10-43 seconds. While very small, this radius is still infinite compared to a point singularity, and its existence would drastically change our ideas about the origin of the universe.

Above the point where the hemispheric cap joins the cone, time runs forward in the usual way, but below it, for earlier times, time gradually turns into space and as we get finally to the bottom of the cap, it disappears altogether. The situation is similar to being at the South Pole and asking which direction would take a person directly toward the North Pole. The answer is that there is no such direction, since all directions at the South Pole are perpendicular to the north-south axis of Earth, which corresponds to time in this analogy.

When exactly at the South Pole, all paths taken eventually lead us northward, but none initially goes in the direction of the north-south axis.

 

[filegraphy]

I was just wondering what acted upon the beginning of our universe to cause it to expand?

 

[bapowell]

I was just wondering what acted upon the beginning of our universe to cause it to expand?

Nobody knows. All we know is that it is expanding. General relativity, when applied to the smooth radiation-dominated early universe, tells us that the universe is either expanding or contracting. We happen to exist in an expanding universe, and so theoretically, the expansion is imposed as a boundary condition.

Probably not nearly as a cool of a response as you were hoping for...

 

[handsbe]

I'm into philosophy and admittedly not had enough physics to support this thought but, let's start at the present, what if the mass in our universe is currently expanding from initial force and/or energy that caused our current existence and over time the mass continues to "clump" together, still under the influence of that initial force(energy), so that it continues to expand. At a future point in time the "clumps" will clump together to form even greater amounts of mass, which will eventually disrupt the affect of initial force/energy and through gravitational pull all the clumps will form together drawing in all that is in space including time (including matter and antimatter) into one "clump" that will, under tremendous pressure and other molecular forces (including unknowns) change the state of matter and energy until, unknown forces begin to expand the "clump" of time, matter and antimatter again at an extremely rapid rate, cycling again and again. Could it be that when "everything" and "nothing" form that "clump" into one in space, that the "clump" may act as an atom "forming" infinite amounts of orbitals which can trigger the initial force? This is a sort of mash up of two ideas, both I developed but the second about orbitals i stuck in there after taking chemistry. Could this idea have any credibility?