Posted on 02/03/2007 7:49:37 AM PST by aculeus
A new cosmological model demonstrates the universe can endlessly expand and contract, providing a rival to Big Bang theories and solving a thorny modern physics problem, according to University of North Carolina at Chapel Hill physicists.
The cyclic model proposed by Dr. Paul Frampton, Louis J. Rubin Jr. distinguished professor of physics in UNC's College of Arts & Sciences, and co-author Lauris Baum, a UNC graduate student in physics, has four key parts: expansion, turnaround, contraction and bounce.
During expansion, dark energy -- the unknown force causing the universe to expand at an accelerating rate -- pushes and pushes until all matter fragments into patches so far apart that nothing can bridge the gaps. Everything from black holes to atoms disintegrates. This point, just a fraction of a second before the end of time, is the turnaround.
At the turnaround, each fragmented patch collapses and contracts individually instead of pulling back together in a reversal of the Big Bang. The patches become an infinite number of independent universes that contract and then bounce outward again, reinflating in a manner similar to the Big Bang. One patch becomes our universe.
"This cycle happens an infinite number of times, thus eliminating any start or end of time," Frampton said. "There is no Big Bang."
An article describing the model is available on the arXiv.org e-print archive and will appear in an upcoming issue of Physical Review Letters.
Cosmologists first offered an oscillating universe model, with no beginning or end, as a Big Bang alternative in the 1930s. The idea was abandoned because the oscillations could not be reconciled with the rules of physics, including the second law of thermodynamics, Frampton said.
The second law says entropy (a measure of disorder) can't be destroyed. But if entropy increases from one oscillation to the next, the universe becomes larger with each cycle. "The universe would grow like a runaway snowball," Frampton said. Each oscillation will also become successively longer. "Extrapolating backwards in time, this implies that the oscillations before our present one were shorter and shorter. This leads inevitably to a Big Bang," he said.
Frampton and Baum circumvent the Big Bang by postulating that, at the turnaround, any remaining entropy is in patches too remote for interaction. Having each "causal patch" become a separate universe allows each universe to contract essentially empty of matter and entropy. "The presence of any matter creates insuperable difficulties with contraction," Frampton said. "The idea of coming back empty is the most important ingredient of this new cyclic model."
This concept jolted Frampton when it popped into his head last October.
"I suddenly saw there was a new way of solving this seemingly impossible problem," he said. "I was sitting with my feet on my desk, half-asleep and puzzled, and I almost fell out of my chair when I realized there was a much, much simpler possibility."
Also key to Frampton and Baum's model is an assumption about dark energy's equation of state -- the mathematical description of its pressure and density. Frampton and Baum assume dark energy's equation of state is always less than -1. This distinguishes their work from a similar cyclic model proposed in 2002 by physicists Paul Steinhardt and Neil Turok, who assumed the equation of state is never less than -1.
A negative equation of state gives Frampton and Baum a way to stop the universe from blowing itself apart irreversibly, an end physicists call the "Big Rip." The pair found that in their model, the density of dark energy becomes equal to the density of the universe and expansion stops just before the Big Rip.
New satellites currently under construction, such as the European Space Agency's Planck satellite, could gather enough information to determine dark energy's equation of state, Frampton said.
A copy of the paper may be downloaded at http://arxiv.org/abs/hep-th/0610213
Source: University of North Carolina at Chapel Hill
Thank you, snarks, those links are fascinating. It's a very amusing thing, reading something with my mind equally divided between "whoa!" and "lies!"
Glad you enjoyed the reading assignment, jim. And even though I know that your "lies!" exclamation is made in fun, let me put in a word for physicists: I know of no instance in which a physicist writing about physics has intentionally lied. Perhaps there is one, but if so, the phenomenon is so exceedingly rare as to be unworthy of notice. At least two reasons for the absence of lies from physics writings should be obvious: (1) physicists are very smart folks, and (2) physicists don't suffer fools (or liars) gladly. The physicist who tried to lie about physics to fellow physicists would get his head handed to him in short order, nor would he ever be trusted again (meaning his career would be over).
Physics is one field about which I have never seriously studied, or for that matter, ever even taken a course in. Is it all so counter-intuitive?
Niels Bohr, founder of the so-called old quantum theory and one of the luminaries of early 20th century physics, said this: "Anyone that is not shocked by quantum theory doesn't understand it." The famous physicist Richard Feynman is reputed to have said this (perhaps stealing a line from the mathematician John von Neumann): "You don't understand quantum mechanics, you just get used to it."
So take heart and don't let counter-intuitiveness be a deterrent to trying to come to grips with some of the ideas of physics.
Thanks. The Guth talk is excellent. Just at my level. I don't have to review a bunch of higher math that I've forgotten just to get through it.Not that I understand it all, of course. I don't. But it answers a lot of questions that have been bugging me (and raises a whole bunch of new ones to bug me in the future, lol!).
I've recommended that Guth essay to other people on other occasions, and I'll surely recommend it again in the future. Glad to know you found it helpful.
OK, I will soldier on... Series-ly, I find this discussion very stimulating, if a bit challenging (did I say "a bit?"). Thanks for the assistance, snarks.
That's my point. If some busybody had been paying attention to every last Biblical rule at the time, they would have at least tried prevent Ruth from coming to Him. They would have at least tried to block the marriage of her and Boaz. Or someone down the line may have pointed out that King David's great-grandmother was a Moabite and caused problems that way.
I can't agree that we should not "compel" others to conform to timeless truisms and "laws" that keep a society civilized.
If you really mean what you are saying, you ARE advocating chaos based on your uncertainty of what God wants. Yet, you yourself don't live your life chaotically. I can discern that much.
The Judeo-Christian tradition is one based on radical individualism, in that the individual answers to God on a one-to-one basis. A set of laws that is based on a given understanding of morality, interferes with that relationship.
Abraham broke with the truisms of his day to found Judaism. For that matter, Jesus went to the cross for breaking the truisms of the law of his day.
Laws should respect that individualism. That means the laws should prevent one (adult) individual from violating the rights of another and provide for the adjudication of disputes, but should go no further.
Will it lead to chaos? I don't know. But a government that respects rights would provide a certain bulwark against that. Even if there is chaos, it is better to transverse a path to God through chaos, than to find the way blocked by order.
What is the conflict between the big bang and the existence of God? I believe that God initiated the big bang.
There exists a FR string theory ping list? No, I don't want to be pinged, but I did read 'The Trouble with Physics' recently, which illuminates the many problems with all these string theories.
Yes, there's a list, no I won't add you unless you ask. Here's the link to the topics list, and I believe there's a topic with a review of that book.
http://www.freerepublic.com/focus/keyword?k=stringtheory
Interesting idea. But it just creates the same problems at a different level. We'll have to wait and see how this shakes out.
L0L.. and not have the decency to say DOH!.. like Homer Simpson when caught at it..
LOLOL! So very true, dear hosepipe!
"Please recommend further reading on this. Links? Articles?"
Most statistics books cover this fact, but don't give the real reason. That's contained in quantum mechanics. It's inherent in the wave nature of energy and matter, fields, and quantization in units of h(Planck's constant). I only have old hard copy's. Fundamentals of modern physics, by Eisberg and Quantum mechanics, by Merzbacher. It's not until one learns much and does the problems, that they can appreciate what I said. In particular, line widths, lifetimes, and WKB calculations.
The first thing one learns is that, the result of any calculation is an expectation value. It is an rms average, the value with the highest probability of occuring. The width of the distribution is a measure of tolerance for particle interactions. As the tolerance goes to zero, the probability of interaction goes to zero, or some much smaller number.
I tried, he never answered my voice mail.
;^)
Deu.23:3....Moabite shall not enter into the congregation of the Lord....
The sidenote in my Bible states:
Moabite. Heb., masc. Therefore not excluding Ruth the Moabitess.
It helped me to see that it referred to the men of Moab only. I hope I didn't interfere.
However, Ruth's father was (I think) a Moabite. All that does is move it back one generation.
OK... So we're saying that the universe spawned some number of new, smaller "universelettes". Each universelette will, in its turn, spawn newer, even smaller universelettes. After some finite stretch of time, wouldn't this get you to universelettes made up of single particles? You can divide by n only so many times before you run out of stuff to divide.
"This cycle happens an infinite number of times, thus eliminating any start or end of time," Frampton said. "There is no Big Bang."
Implications:
All cycles have a starting / stopping point. No perpetual motion.
There are other universes aka there is a multiverse. There is an escape valve to escape the heat death of our universe. So, how can we get there?
I just assume that it means any females were excluded from the curse and that would include their offspring, male or female. It applied to males only and to their direct male offspring.
It sounds like it's splitting hairs but it's something to consider.
It sounds like it's splitting hairs but it's something to consider.
It's not the first time I've heard it and it's good pilpul, to use the Hebrew term for this sort of close Biblical discussion.
Thing is, that supports my original point. The danger of using the Bible as basis of law is that the the wrong half of the split hair could easily be the one chosen by the legal system.
"No, but it would be helpful to not speak in oxymorons. If it's "God's creation" that means it was created, ie, not "endless."
Unless words don't have meanings."
Haminahamina wha???? How is "God's creation" an oxymoron?
.....and what's with the split infinitive?!??!!
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