Posted on 08/04/2006 4:26:21 AM PDT by PatrickHenry
The question of what happened before the Big Bang long has frustrated cosmologists, both amateur and professional.
Though Einstein's theory of general relativity does an excellent job of describing the universe almost back to its beginning, near the Big Bang matter becomes so dense that relativity breaks down, says Penn State physicist Abhay Ashtekar. "Beyond that point, we need to apply quantum tools that were not available to Einstein."
Now Ashtekar and two of his post-doctoral researchers, Tomasz Pawlowski and Parmpreet Singh, have done just that. Using a theory called loop quantum gravity, they have developed a mathematical model that skates right up to the Big Bang -- and steps through it. On the other side, Ashtekar says, exists another universe with space-time geometry similar to our own, except that instead of expanding, it is shrinking. "In place of a classical Big Bang, there is in fact a quantum Bounce," he says.
Loop quantum gravity, one of the leading approaches to the unification of general relativity with quantum physics, was pioneered at the Institute of Gravitational Physics and Geometry at Penn State, which Ashtekar directs. The theory posits that space-time geometry itself has a discrete "atomic" structure, Ashtekar explains. Instead of the familiar space-time continuum, the fabric of space is made up of one-dimensional quantum threads. Near the Big Bang, this fabric is violently torn, and these quantum properties cause gravity to become repulsive, rather than attractive.
While the idea of another universe existing prior to the Big Bang has been proposed before, he adds, this is the first mathematical description that systematically establishes its existence and deduces its space-time geometry.
"Our initial work assumes a homogenous model of our universe," Ashtekar acknowledges. "However, it has given us confidence in the underlying ideas of loop quantum gravity. We will continue to refine the model to better portray the universe as we know it and to better understand the features of quantum gravity."
***
Abhay Ashtekar is holder of the Eberly family chair in physics and director of the Institute for Gravitational Physics and Geometry in the Eberly College of Science. He can be reached at ava1@psu.edu.
The finding reported above was published in Physical Review Letters in May 2006. The research was sponsored by the National Science Foundation, Alexander von Humboldt Foundation, and the Penn State Eberly College of Science.
I just love science. It gives me something tanglible to explain some of those things around me that I don't understand.
I have a whole lot of questions for God. He's got the time to answer them...
All that now exists bursts from the singularity in a nano second and that wasn't an explosion? What was all of the light and heat and matter flying through space,old Jack Benny jokes?
God spoke and BANG, the universe came into existence.
I like it!
A bit of foreplay, I'd imagine.
All that light and heat and matter weren't flying through anything. The Big Bang was an explosion OF space, not of things in space. ANd the universe is still expanding from the Big Bang. Things are getting farther apart, but not from moving through space. More space is coming into existence between things.
The Big Match lit the Big Fuse?
John 1:1
Yes, it's an old joke. I like it too.I use it on humans who think they know how the universe began without God's help. It either cracks them up or they become very quiet.
What's the definition of "explosion?" If you slow down an explosion, what is actually occurring? Rapid expansion?
Iran declared war on Israel?
I notice the Evos are not waxing techno on this one. They are leaning more to the lame joke and personal attack mode. The technobabble is not as well developed in the area of pre-bigbang pseudoscience.
"He was preparing Hell for those who ask these kind of questions" ;^)
Perhaps some of us post opinions only in areas we know well ===> Placemarker <===
It was obviously methaphor.
What did the singularity exist in, nothingness? If so what was the nothingness comprised of, because if nothingness existed it was comprised of something or a total absence of something to which it could be compared.
Bookmarking for later.
If there is a steady state over time, the Big Bang disturbed the trend. The post yesterday describing galaxies headed in a common direction indicates a reversion to a point and a pre big bang site.
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