Posted on 03/16/2006 11:31:54 AM PST by The_Victor
Physicists announced Thursday that they now have the smoking gun that shows the universe went through extremely rapid expansion in the moments after the big bang, growing from the size of a marble to a volume larger than all of observable space in less than a trillion-trillionth of a second.
The discovery — which involves an analysis of variations in the brightness of microwave radiation — is the first direct evidence to support the two-decade-old theory that the universe went through what is called inflation.
It also helps explain how matter eventually clumped together into planets, stars and galaxies in a universe that began as a remarkably smooth, superhot soup.
"It's giving us our first clues about how inflation took place," said Michael Turner, assistant director for mathematics and physical sciences at the National Science Foundation. "This is absolutely amazing."
Brian Greene, a Columbia University physicist, said: "The observations are spectacular and the conclusions are stunning."
Researchers found the evidence for inflation by looking at a faint glow that permeates the universe. That glow, known as the cosmic microwave background, was produced when the universe was about 300,000 years old — long after inflation had done its work.
But just as a fossil tells a paleontologist about long-extinct life, the pattern of light in the cosmic microwave background offers clues about what came before it. Of specific interest to physicists are subtle brightness variations that give images of the microwave background a lumpy appearance.
Physicists presented new measurements of those variations during a news conference at Princeton University. The measurements were made by a spaceborne instrument called the Wilkinson Microwave Anistropy Probe, or WMAP, launched by NASA in 2001.
Earlier studies of WMAP data have determined that the universe is 13.7 billion years old, give or take a few hundred thousand years. WMAP also measured variations in the cosmic microwave background so huge that they stretch across the entire sky. Those earlier observations are strong indicators of inflation, but no smoking gun, said Turner, who was not involved in the research.
The new analysis looked at variations in the microwave background over smaller patches of sky — only billions of light-years across, instead of hundreds of billions.
Without inflation, the brightness variations over small patches of the sky would be the same as those observed over larger areas of the heavens. But the researchers found considerable differences in the brightness variations.
"The data favors inflation," said Charles Bennett, a Johns Hopkins University physicist who announced the discovery. He was joined by two Princeton colleagues, Lyman Page and David Spergel, who also contributed to the research.
Bennett added: "It amazes me that we can say anything at all about what transpired in the first trillionth of a second of the universe."
The physicists said small lumps in the microwave background began during inflation. Those lumps eventually coalesced into stars, galaxies and planets.
The measurements are scheduled to be published in a future issue of the Astrophysical Journal.
What you don't seem to be able to comprehend is that the physics of a superhot universe would be quite different in many ways from the physics of a cold universe (the modern universe). While one can deduce circumstances in a superhot universe from observations in our cold universe (because the physics ultimately depend on the same 'laws'), you cannot entirely recreate them. That is because any simulation of the superhot universe will necessarily take place within a cold universe.
But, I understand that you reject the logical rules of rational deduction. That is the very crux of what being an obscurantist (i.e., you) is all about. Nonetheless, I may attempt to explain the relevant particle physics (and the problems with the framing of your question) tonight, when I might have the time. Right now, I have to go.
"What force is doing the compressing then, and why would that force change merely because extra space suddenly existed...if, as you claim, you aren't ascribing a Force to space?"
What I was implying was this: And hopefully I can put it into words properly they way I see it.
Matter needs space to exist in. If all of space (the entire universe) is size x, than all matter contained within must fit in volume x. As the universe expanded,, to simplify as much as possible.. it made more room for the matter to spread out, and so it did to equalize the pressure. Nobody was there when this happened so nobody can possibly know, but all evidence found so far suggests that the universe was much smaller, hotter, and danser in the distant past. The logical conclusion for how it gotlike it is today is expansion, spreading out of matter, and subsequent cooling (spreading of energy density).
Then just admit that "we've never seen matter cool through particle transformation" rather than dance around the key point.
Inflation Cosmology and the Big Bang require a unique, never-seen method of cooling (among other never-seen things e.g. unified field rather than the 4 Forces, unified field "overwhelming" Relativity, etc.).
The concept of space isn't something that most people understand, and it's hard to explain, since it requires stepping away from observable reality."
Is this what you scientific guys call thinking outside the box?
That would be a ridiculous admission, because it would be a lie, that only someone deeply ignorant would admit (or ask for an admission of).
Here is a classic paper from Enrico Fermi describing the cooling of matter via particle transformation:
The Ionization Loss of Energy in Gases and in Condensed Materials
Nah, not really. It's the rules of observation. You cannot see what is outside your field of vision. Our observations are limited to our universe.
And now I really have to go! Anything further will just have to wait.
I'm still holding out for the Big Rip cataclysm theory (though I don't hear much about this one any more...)
No, Fermi is talking about transiting particles (e.g. electrons) losing their own energy *to* the medium being transited (e.g. ionized gases).
Yeah, I know, but you forgot to include the caveat in that post, and I couldn't resist giving you a taste of your own medicine. :)
Regardless, I won't have time to get back to this in a serious way until tonight. I shouldn't even be distracted here now.
OK, I had that coming!
Very good. And over my head. But that's OK. At least I know a bit more of what it is that I don't know.
OK, to be done with this, here's the shortest answer I'd give to your questions:
No, we have not observed the mechanism by which the pre-inflation universe 'cooled'; in fact, with curvatures of spacetime as extreme as they would've been in the Planck Era, we cannot even mathematically define the total energy of the system, and conservation of energy becomes inoperable. Indeed, there are a number of problems with the way we've been describing and defining pre-inflation conditions (including the way we've used the terms "matter" and "cooling"), and I am complicit in that, but I'll just let that go as you do not seem to be the type of person who cares anyhow. LOL
In any case, we cannot recreate these conditions unless we could curve spacetime as extremely as it would've been before inflation, and we cannot do that at this juncture. From a mathematical standpoint, we will not have complete answers to these questions until we have a quantum theory of gravitation (i.e., a Theory of Everything), which we do not have, and it was my error to imply otherwise. And yes, I was dancing away from this point, not so much consciously, but because I'm as unsatisfied as anyone at not having all the answers. :)
So, to reiterate (and to state the rather obvious), you are correct to say that Inflation Theory requires the mathematical deduction of unique, never-seen conditions. I shouldn't have resisted this characterization to begin with.
Wow. I'm humbled.
Thanks.
Patience
Prime
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