The Big Bang AKA Where The **** Did It All Start?

VEGANGELICA · 08-03-2011, 11:30 PM

Quote:

Originally Posted by lucifer_sam

non-sequitur, literally meaning "it does not follow", from:

(1) When the Big Bang is described as the event during which the cosmos went through a superfast "inflation," expanding from the size of an atom to the size of a grapefruit in a tiny fraction of a second (as shown in Jackhammer's original post: http://ssscott.tripod.com/bang.jpg), I imagine the universe as having consisted of an infinite space full of those tiny atom-sized areas expanding.

(2) The universe would then be an infinite space where expansion occurs at every point within that space.

(3) If the universe at the time of the Big Bang was an infinite space of dense matter and expanded at every point within that space, then we would have something without limits that expands yet isn't actually getting "larger" because the space was infinite to begin with.

I've boldfaced the parts that I can't follow. It wasn't just matter expanding during the Big Bang, it was space itself (which she later remarked about).

Yes, I meant that space itself was expanding during the Big Bang (and continues to expand). That is the meaning of the quote about the universe expanding from the size of an atom to the size of a grapefruit in a tiny fraction of a section. I assumed we were all in agreement about space itself expanding, so I didn't emphasize it.

I am saying that perhaps the universe, at the time when people describe it as the size of an atom, a tiny pinpoint, was then composed of an infinite number of such tiny pinpoints. This would thus be infinite space. (The idea was suggested to me by a Scientific American Magazine article that I love, called "The End of Cosmology? An accelerating universe wipes out traces of its own origin," by Lawrence M. Krauss and Robert J. Scherrer, March 2008: http://genesis1.asu.edu/0308046.pdf.)

Then, during the Big Bang, all those tiny pinpoints of space expanded, leading to an infinity of space that is expanding yet is no bigger than the space before, since it was infinite to begin with.

(Sounds paradoxical and weird, but so is the idea of space expanding, so I can roll with it.

)

One of those atom-sized pinpoints expanded to give rise to what we know as the observable universe.

My point was that I don't imagine the universe as a single, atom-sized space that expanded during the Big Bang, but as an infinite volume in which the space at all pinpoints within that volume expanded rapidly during the Big Bang.

lucifer_sam · 08-04-2011, 12:03 AM

Quote:

Originally Posted by VEGANGELICA

Yes, I meant that space itself was expanding during the Big Bang (and continues to expand). That is the meaning of the quote about the universe expanding from the size of an atom to the size of a grapefruit in a tiny fraction of a section. I assumed we were all in agreement about space itself expanding, so I didn't emphasize it.

I am saying that perhaps the universe, at the time when people describe it as the size of an atom, a tiny pinpoint, was then composed of an infinite number of such tiny pinpoints. This would thus be infinite space. (The idea was suggested to me by a Scientific American Magazine article that I love, called "The End of Cosmology? An accelerating universe wipes out traces of its own origin," by Lawrence M. Krauss and Robert J. Scherrer, March 2008: http://genesis1.asu.edu/0308046.pdf.)

Then, during the Big Bang, all those tiny pinpoints of space expanded, leading to an infinity of space that is expanding yet is no bigger than the space before, since it was infinite to begin with.

(Sounds paradoxical and weird, but so is the idea of space expanding, so I can roll with it.

)

One of those atom-sized pinpoints expanded to give rise to what we know as the observable universe.

My point was that I don't imagine the universe as a single, atom-sized space that expanded during the Big Bang, but as an infinite volume in which the space at all pinpoints within that volume expanded rapidly during the Big Bang.

Ah. What you're describing isn't really a 'singularity' event, then.

I found that an extremely illuminating article, but I couldn't find anywhere in it that brushed on the idea that you're introducing. In fact, there wasn't much discussion of what happened during the initial phase of the Big Bang. The cosmologists go on to suggest that they really can't tell what happened in the beginning:

Quote:

Expansion probably accelerated early in cosmic history as well, erasing almost all traces of the preexisting universe, including whatever transpired at the big bang itself.

Other materials I've read that touch on it suggest otherwise (in other words, that the Big Bang was indeed a singularity event, both in matter and space), but I would be extremely interested in seeing a scientific journal that supports your hypothesis.

VEGANGELICA · 08-11-2011, 10:22 AM

Quote:

Originally Posted by lucifer_sam

Ah. What you're describing isn't really a 'singularity' event, then.

I found that an extremely illuminating article, but I couldn't find anywhere in it that brushed on the idea that you're introducing. In fact, there wasn't much discussion of what happened during the initial phase of the Big Bang. The cosmologists go on to suggest that they really can't tell what happened in the beginning:

Other materials I've read that touch on it suggest otherwise (in other words, that the Big Bang was indeed a singularity event, both in matter and space), but I would be extremely interested in seeing a scientific journal that supports your hypothesis.

After I made that previous post, I did some more reading to try to find out what astrophysicists actually say if they appear to question the singularity of the Big Bang. This led me to an article (see below) about cosmologists who hypothesize that the universe arose from an earlier universe: Sean Carroll, Assistant Professor in Physics at U. of Chicago, and graduate student Jennifer Chen.

Their views (as best I can understand them) were the closest I could find to my naive imaginations only in that they hypothesize a universe existed out of which ours arose...so there could have been infinite space before our universe.

They hypothesize that the universe of which we are a part may have arisen from a small portion of a universe (still in existence, I assume) where space had stretched very very far and matter was spread extremely thinly (as is occurring in our universe). This would mean that "inflation" didn't start with our universe but had occurred before (and for all we know is still occurring somehow, outside our universe).

Their proposed initial birthplace of our universe as an infinite area of expanding space and dispersed matter is very different from my incorrect imagination of the birthplace as being an infinite area of dense (compact?) space and dense matter:

Quote:

Astrophysicists attempt to answer mystery of entropy

The big bang could be a normal event in the natural evolution of the universe that will happen repeatedly over incredibly vast time scales as the universe expands, empties out and cools off, according to two University of Chicago physicists.

“We like to say that the big bang is nothing special in the history of our universe,” said Sean Carroll, Assistant Professor in Physics. Carroll and graduate student Jennifer Chen electronically published a paper last month describing their ideas at [hep-th/0410270] Spontaneous Inflation and the Origin of the Arrow of Time.

Previous researchers have approached questions about the big bang with the assumption that entropy in the universe is finite. Carroll and Chen take the opposite approach. “We’re postulating that the entropy of the universe is infinite. It could always increase,” Chen said.

To successfully explain why the universe looks as it does today, both approaches must accommodate a process called inflation, which is an extension of the big bang theory. Astrophysicists invented inflation theory so they could explain the universe as it appears today. According to inflation, the universe underwent a period of massive expansion in a fraction of a second after the big bang.

Carroll and Chen argue that a generic initial condition is actually likely to resemble cold, empty space—not an obviously favorable starting point for the onset of inflation.

But even empty space has faint traces of energy that fluctuate on the subatomic scale. As suggested previously by Jaume Garriga of Universitat Autonoma de Barcelona and Alexander Vilenkin of Tufts University, these fluctuations can generate their own big bangs in tiny areas of the universe, widely separated in time and space.

The new universes created in these big bangs will continue the process of increasing entropy. In this never-ending cycle, the universe never achieves equilibrium. If it did achieve equilibrium, nothing would ever happen. There would be no arrow of time.

When I wrote that my previous (I now realize incorrect) imagination of our universe's origin from infinite space was suggested to me by that Scientific American Magazine article, (http://genesis1.asu.edu/0308046.pdf), I didn't mean that they suggested the idea but that something they wrote made me wonder if the initial state of our universe could have been infinite space. I should have clarified that, Lucifer.

They had a figure showing one part of our universe...our observable universe and part of the universe that has become unobservable to us due to space's inflation. They said that aliens anywhere else in our universe would see space expanding in the same way, and that perhaps the universe is infinite.

I then imagined the deflation (?) of our universe, as I think back through time, to try to picture the initial state. I imagined that if one small speck of space could inflate to create an infinite universe, then a region equal to ten specks could inflate to create an even greater infinity of space

... so then an infinite number of specks of original space could have expanded into an even greater infinity of space! That's how I came up with my wild idea that has no basis in any theory.

It all hinged on the idea that I haven't heard it said that our universe arose out of an infinitesimally small point, but rather out of an atom-sized space...so then I started imagining lots of those atom-sized spaces as one giant original space, and what expansion of that would look like.

Back to Carroll and Chen, though: I do feel it makes more sense for our universe to have arisen from another universe that had the same characteristics as ours (continual, accelerating inflation of space and dispersal of matter), rather than have our universe pop into existence out of nothingness. That doesn't answer how it all began, though, if there was a beginning!