No Big Bang? Endless Universe Made Possible by New Model

Physorg.com ^ | January 30, 2007 | University of North Carolina

[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

[navyguy]

"Still denying God. Something BIGGER than they are."

Its a scientific theory. It makes no mention of God and it posits no hypothesis about God. Its a theory about matter and energy, not the existence of God.

[nmh]

"Its a scientific theory. It makes no mention of God and it posits no hypothesis about God. Its a theory about matter and energy, not the existence of God."

First off it's nothing more than a HYPOTHESIS.

Were YOU there? Can you repeat it as required by a "theory"? Of course not!

Id denies God by it's very hypothesis.

The ORDER is wrong for starters ... I know, the Bible is some old dusty book to be chuckled at but hey, it is God's word. It is not in agreement with man's word that btw, keeps "evolving" .

[editor-surveyor]

Anyone afraid to use the word "theory"?

A 'model' is much looser than a theory. Models tend to be political creations, much like 'studies.' Global warming is another 'model.' Models can leap over their deficiencies by simply ignoring them.

[capitalist229]

there is nothing wrong with trying to figure out how it works.

Eating from the "tree of knowledge" is expressly forbidden and will get you thrown out of Paradise.

If Eve had just eatten an orange instead...

BUMP

[snarks_when_bored]

If nothingness is even the slightest bit unstable, then there will come a moment when a small patch of negative pressure pops into being. Once such a patch appears, inflation begins and then continues into the infinite future, spawning along the way an infinite number of universes (Guth's 'pocket universes'). What's interesting about Frampton's proposal is how it allows for a kind of cyclicity in the production of those universes that avoids the problem of entropy increase (and consequent lengthening of cyclic bounce phases) that has dogged previous cyclic universe theories.

According to Frampton, as dark energy accelerates the expansion of any specific universe, there comes an instant (he calls it the 'turnaround' instant) at which all matter and energy have been diluted into the vast emptiness of expanding space. At that instant,

...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."

If each little causally independent patch is essentially empty of matter and entropy, then, when that 'small' patch contracts, it doesn't carry the entropy baggage of the previous expansion phase (the entropy has been diluted away), and so the multicyclic growth of entropy that messed up previous cyclic universe theories is avoided. Each little patch of pregnant emptiness contracts rapidly, and then bounces into an inflation phase that once again produces an expanding universe.

Imagine an exploding fireworks star shell, each bit of flame expanding outward and gradually dimming, and then at the moment of extinction of each bit, each spot in the sky where the bit winks out contracts rapidly and explodes into a new fireworks star shell universe, and then each one of those universes experiences the same process, time after time, endlessly repeating. You get a nested sequence of star shell universes...

Note that at each stage, each star shell burst gives rise to a vast number of new universes; no burst, with all of its flaming bits, collapses back onto its original burst site, as a Big Bang model with expansion and collapse would have it.

...just my quick take on what I've read so far.

[Harry Pothead]

If you are a hardcore creationists please do not read this post. I do not want to start a fight with anyone.

The expansion contraction theory/hypothesis/whacked out idea,
has always appealed to me on an emotional level. It explains eternity to me in a way I can understand, no beginning no end.

[El Gato]

"There is no Big Bang."

It sounds like there are instead a near infinite number of "little bangs". It also sounds like, unless conservation of mass-energy is violated, that on each cycle, the many universes must get smaller and smaller.

The model would still seem to require a first "Big Bang".

Both of these observations may be the result of the verbal description not really reflecting the mathematics of the model.

[El Gato]

Models tend to be political creations, much like 'studies.'

Oh please, a model may be part of a theory, or it may be based on a theory. I model all sorts of things, mostly based on Newton's theories, even though those have long been known to be only approximations of Einstein's theories (and others) which are probably only approximations as well.

For example a flight simulator is based on various theories of aerodynamics and Newton's laws. It's not a real airplane, but just a "model" of one. A very good model in most cases.

[jwalsh07]

If nothingness is even the slightest bit unstable, then there will come a moment when a small patch of negative pressure pops into being.

How is nothing unstable? Does zero ever become 1 or -1 if I leave it on my notepad long enough? If not, why not? Moreover how do pressure gradients exist in nothing?

Nothing from nothing leaves nothing......

[taxesareforever]

"This cycle happens an infinite number of times, thus eliminating any start or end of time,"

And now for theory number 1,000,0000, 001.

[Torie]

It is a head scratcher. I read about cosmic speculations of something being generated out of nothing in high school. Sometimes one has to make the books balance with a stub number, and assume one just missed it.

[investigateworld]

Your thoughts?

[jwalsh07]

WHich is exactly what Einstein did in his field equations in order to avoid a beginning. The Catholic Monk who posited BBT disagreed and Hubble settled the issue. Albert, to his credit, eventually embraced the science that his world view initally denied.

[snarks_when_bored]

How is nothing unstable? Does zero ever become 1 or -1 if I leave it on my notepad long enough? If not, why not? Moreover how do pressure gradients exist in nothing?

Nothing from nothing leaves nothing......

The emptiest-seeming vacuum of deep space is seething with virtual particle-antiparticle pairs which wink into and out of existence in very small fractions of a second. That's physical nothingness. At any moment, there is a non-zero (albeit exceedingly tiny) probability for just about anything to pop into and out of existence. The curious thing about a patch of negative pressure is that if it pops into existence, it immediately begins to inflate.

If the physical is all there is or has ever been, that's the only kind of nothingness with which physics must concern itself.

[jwalsh07]

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.

Any thoughts on how one would observe this? :-} Just being snarky. We are stuck in our own little universe. Nothing anybody can say can falsify this paragraph. Is is so because the scientist said it is so. So there!

[Coyoteman]

A new cosmological model....

Anyone afraid to use the word "theory"?

Theories and models are different. From my list of definitions:

Theory: a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena; "theories can incorporate facts and laws and tested hypotheses." Addendum: "Theories do not grow up to be laws. Theories explain laws." (Courtesy of VadeRetro.)

Theory: A scientifically testable general principle or body of principles offered to explain observed phenomena. In scientific usage, a theory is distinct from a hypothesis (or conjecture) that is proposed to explain previously observed phenomena. For a hypothesis to rise to the level of theory, it must predict the existence of new phenomena that are subsequently observed. A theory can be overturned if new phenomena are observed that directly contradict the theory. [Source]

When a scientific theory has a long history of being supported by verifiable evidence, it is appropriate to speak about "acceptance" of (not "belief" in) the theory; or we can say that we have "confidence" (not "faith") in the theory. It is the dependence on verifiable data and the capability of testing that distinguish scientific theories from matters of faith.

Model: a simplified representation designed to illuminate complex processes; a hypothetical description of a complex entity or process; a physical or mathematical representation of a process that can be used to predict some aspect of the process; a representation such that knowledge concerning the model offers insight about the entity modelled.

[Torie]

One would have to draw extremely clever inferences about the over the yonder from the transponder with which to ponder. And there you have it.

[therut]

Sounds like a physics "myth" too me. This is nothing but physics Creation Myth.

[jwalsh07]

The emptiest-seeming vacuum of deep space is seething with virtual particle-antiparticle pairs which wink into and out of existence in very small fractions of a second.

Deep space is not nothing, it is deep space seething with virtual particle-anti particle pairs. Virtual particles have energy as a prerequisite. You see the problem here?

That's physical nothingness.

Nonsense, it is physical somethingess as evidenced by your previous sentence.

At any moment, there is a non-zero (albeit exceedingly tiny) probability for just about anything to pop into and out of existence.

No, quantum fluctuations require energy as a prerequisite. Energy, once again, is something. When has "just about anything" been observed to pop into existence absent extant energy?

The curious thing about a patch of negative pressure is that if it pops into existence, it immediately begins to inflate.

When have pressure gradients ever been observed in nothingness? For that matter when has nothingness ever been observed? Don't you think you should isolate nothingness before you speculate on what can or cannot pop out of it?

[airborne]

For some, every reason conceivable is a possibility.

Except for the concept of God!