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.
Incorrect. It's not a valid answer to make a statement as if scientific and then to come back with "We don't know." If you don't know, then don't make the statement in the first place.
LOL!! I like that. Cheers!
"....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."
God called, He wants His marble back.
There is a really good article about it at post 118. When you learn something (and remember it) at age 10, and then quit keeping up with it for 30+ years, one recollections might well have been proven wrong in that time.
Awwwwwwwww, is it time for the big crunch already. I was just starting to have fun.
Actually, it's Einstein that is saying that it is possible. We're just plugging in various values for his cosmological constant based on different levels of vacuum energy.
Everything.. Not all democrats are Moonbats.. some are Turtles.. with the world on their shoulders..
Then why and how was this gravitational force overcome originally back when matter was even closer together than today?" - Southack
"We do not know the answer to that question, but we're working on finding an answer." - MinerMan
You can't have it both ways. You can't claim that gravity holds matter "relatively static" on the one hand and then punt...saying "We don't know" when asked why matter isn't static (e.g. pre-big-bang versus today).
Either we know what gravity does or we don't. Stop trying to have it both ways. Do we know, or not?!
To the infinite stack of turtles underneath. :)
"At the limits of the universe, many, many billions of years ago, we cannot see any further, since we have nothing with which to see. We can see remnants of the original energy that formed the universe, but, beyond that, there is nothing to measure, and nothing we can measure with."
...
"Just think of nothing when you wonder what the universe is expanding into. Simply nothing."
Very well put.
Also, we're not reaching out and looking "at the edge of the universe". What we're really doing is opening up sensors' eyes and detecting whatever from out there is coming to hit us here. It's quite passive, really, although we're accustomed to using the active voice. Really we're seeing a flat picture, and then converting that to a 3-d (or 4-d...or 21-d!) picture. And that might make a difference.
To return to that business of the "grid", the difference between space-time and void nothingness would be that within space-time there's a grid which warps in the presence of matter. Or perhaps it's matter that makes the grid and warps it (voila le gravitron!). Where there's no matter (I'm subsuming all particles of energy into "matter" for this purpose), there's no relative grid at all, because there's nothing to be relative to anything else, and there's no sequence of anything, so no time, and there's no fixed grid to be warped by gravitrons, or gravitrons to make a grid. There's just NOTHING, until something sweeps close enough to structure it.
I've taken a couple of mental trips to nothing. As long as you can look back and see something, anything, it's not nothing. Only when there's nothing to be relative to is there nothing.
WHERE is "nothing"?
It's in the same place that the dream you will have tomorrow night is.
It doesn't need to be expanding into anything.
It is, but the distance between the Sun and us is too small to show any effect.
Are you joking?
He clearly made a statement about what we know as an observed phenomenon in the present and then expressed that we don't have an answer to a different situation in the past.
Kind of like saying we know the bird crashed into the window but we don't know where it took off from. Is that a contradiction?
"Time is as fully tangible as our dimensions of size. Entropy gives time its direction. It's unit measure (seconds) is arbitrary just as the unit measure of length is arbitrary (meters), but in both cases the dimensions are fully tangible and provable. There are (at least) four dimensions. Three spatial, one temporal."
The highest speculative science resolves itself on definitions, and reposes in words. Our language, of course, is not made for this stuff, and starts to strain and tear.
Time is mathematically provable.
But it is in no sense whatever "tangible".
"Tangible" means you can touch it.
You can't.
And that matters to what I was saying about dimensions.
You can prove mind too.
And mind is extremely powerful, and has its own strange rules we don't fully understand.
But it's not tangible either.
We don't usually define mind as a "dimension", but we certainly COULD.
And that was my point.
There are things that are more solid than other things.
Three dimensions ARE tangible. We can touch them.
The fourth, time, is speculative. We may be able to prove some things mathematically and make assumptions from observations, but no, time is not tangible.
Which places it on a different plane of certitude than the three geometric dimensions.
Gravity isn't tangible either, at least not until we actually see a gravitron, but the effects are, even to 2 year olds ("Fall down, go boom!")
Time? There is sequentiality, as we describe it. There seems to be "something" there, but it's a concept, much more abstract than mind. Mind is more obvious than electromagnetism, strong or weak force, but we've not even attempted, other than metaphysically, to insert MIND into dimensions or forces. Too hard. It's not tangible either, but it's more obvious than time.
Are there any mathematically defined 'spaces' that we could talk about the universe 'expanding' into?
If I have a two dimensional locally Euclidean surface (a balloon for example) it should be easy to show that it's deformation over time can be embedded in a three dimensional Euclidean space.
Are there any metrics or spaces that can be used to embed a locally Lorentzian space curved by and evolving according to General Relativity?
Maybe we can throw a bone to those of us who need to have a 'space' that space is expanding into.
Yeah, but at least then you can compute cross-sections.
I think string theory is interesting mathematics too, but if I can't calculate graviton-graviton scattering yet, it's still just mathematics. (Yes, I know you need to choose a vacuum. Pick your favorite.)
Having assumed the initial expansion, however, the answers are what I already gave you: gravity (plus cooling, to put it simply); dark energy (or whatever you want to call it); and physical laws weren't different (the universe didn't 'travel' faster than light; rather, timespace was stretched and light stretched with it).
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