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.
Impressive math no doubt, but not worth throwing over the currently popular model.
That is already answered. A superior question would be 'why did something explode from nothing.'
Empty of some things, packed to the gills with other things. No part of the universe is absolutely empty. If nothing else there is that three degree microwave radiation everywhere.
The Long Hiss. (Imagine sound of a lighted fuse.)
Actually, I was referring to matter in space. It is mostly empty, but as you correctly pointed out, there is a lot of matter concentrated in a few places (e.g. neutron stars). But my comment still stands. Even what we call solid objects, like my desk or your car, are mostly empty on the atomic scale. There is still a lot of room for compression.
How matter is brought into existence through creation is not the same as asking for the origin of God.
You should know that something is eternal. If matter is eternal, it is divine.
Absolute time.. WHAT a concept...
A Rolex moment with a see in the dark radium dial.. for most..
An ancient chinese water clock for others..
For those in the moment.. time is absolute..
Hold on there pard. There are some folks who hold quantum interference as prima facie evidence of a multiverse - it is the different universes interacting. And then there's the proposed test (by Deutsch I think) of using a quantum computer to test the multiverse. IIRC, he proposes a quantum computer programmed to solve a yes/no problem. If the computer tells you it defintely determined the answer but can't say what it was, then half of the computation was done in a different universe.
For my part both are too tenuous to be convincing.
Even such a simple thing as an electron is not a solid particle with a given dimension. It cannot be said that there is empty space between a proton and an electron in a simple hydrogen atom since for all we know the electron fills the entire space. We cannot say what the diameter of a proton might be except by specifying a process of bouncing another proton off it and measuring the bounce. What most call solid matter is not solid matter but could well be nothing at all but some multidimensional curvature of space. If nothing else, the curvature exists and if that is what solid matter is then space is filled completely.
Not only isn't that obvious, it obviously wan't given past behavior.
Hmmmmm....probabry much rubrication.....
Methaphor--an illustration by a chemically-enhanced orator.
Thank you for making the post that I felt compelled to make ...LOL
What has atheism to do with the discussion?
The Big Bang is more readily likened to an inflating balloon.
I wasn't there when O.J. slaughtered his wife, either, but I have a high degree of confidence he did it.
No, it takes knowledge of the evidence. That you are incapable of understanding a subject has no bearing on the subject's validity. A three-year-old doesn't understand calculus; it does not mean calculus is crap.
So who designed God's universe?
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