Bizarro
Posted on 05/04/2006 12:02:17 PM PDT by PatrickHenry
Big bounces may make the Universe able to support stars and life.
A bouncing universe that expands and then shrinks every trillion years or so could explain one of the most puzzling problems in cosmology: how we can exist at all.
If this explanation, proposed in Science1 by Paul Steinhardt at Princeton University, New Jersey, and Neil Turok at the University of Cambridge, UK, seems slightly preposterous, that can't really be held against it. Astronomical observations over the past decade have shown that "we live in a preposterous universe", says cosmologist Sean Carroll of the University of Chicago. "It's our job to make sense of it," he says.
In Steinhardt and Turok's cyclic model of the Universe, it expands and contracts repeatedly over timescales that make the 13.7 billion years that have passed since the Big Bang seem a mere blink. This makes the Universe vastly old. And that in turn means that the mysterious 'cosmological constant', which describes how empty space appears to repel itself, has had time to shrink into the strangely small number that we observe today.
Cosmic disagreement
In 1996, it was discovered that the universe is not only expanding but is also speeding up. The cosmological constant was used to describe a force of repulsion that might cause this acceleration. But physicists were baffled as to why the cosmological constant was so small.
Quantum theory suggests that 'empty' space is in fact buzzing with subatomic particles that constantly pop in and out of existence. This produces a 'vacuum energy', which makes space repel itself, providing a physical explanation for the cosmological constant.
But the theoretically calculated value of vacuum energy is enormous, making space far too repulsive for particles to come together and form atoms, stars, planets, or life. The observed vacuum energy, in contrast, is smaller by a factor of 10120 - 1 followed by 120 zeros. "It is a huge problem why the vacuum energy is so much smaller than its natural value," says Carroll.
You're special
One of the favoured explanations is the 'anthropic principle'. This suggests that in the apparently infinite Universe, the cosmological constant varies from place to place, taking on all possible values. So there's bound to be at least one region where it has the right size for galaxies and life to exist - and that's just where we are, puzzling over why our observable Universe seems so 'special'.
But this runs against the grain for physicists, who prefer to be able to explain our Universe in one shot. "Relying on the anthropic principle is like stepping on quicksand," Steinhardt and Turok write. They think they have a more satisfying explanation.
They have seized on an idea first proposed by physicist Larry Abbott in 1985: that maybe the vacuum energy was once big but has declined to ever smaller values. Abbott showed that this decay of the vacuum energy would proceed through a series of jumps, with each jump taking exponentially longer than the last. Over time, the Universe would spend far longer in states with a vacuum energy close to zero than with a high vacuum energy.
A long, long time ago
The problem was that Abbott's calculations implied that by the time the vacuum energy decayed to very small values, the expansion of space would have diluted all the matter within it so much that it would effectively be empty.
The cyclic universe gets around this problem, say Steinhardt and Turok. With cycles of growth and collapse taking a trillion years or so, and no limit to how many such cycles have preceded ours, there is plenty of time for the vacuum energy to have decayed almost to zero. And each cycle would concentrate matter during the collapse phase, making sure that the Universe doesn't end up empty.
Steinhardt and Turok say that their idea is testable. The cyclic model predicts that the Big Bang induces gravity waves in space, which physicists are now hunting for. And the decay of the vacuum energy predicts new types of fundamental particles called axions, which may also be detectable.
"It's an interesting idea," says Carroll. He confesses that he has other worries about the cyclic-universe model that temper his enthusiasm. But the wackiness of it doesn't bother him. "Any explanation is quite likely to be extreme," he says, "because all the non-extreme possibilities have already been thoroughly explored."
Well, don't throw out string theory just yet. You can combine it with the Swiss Cheese theory and have String Cheese Theory.......
I am not saying they should ignore reality. However, I do think that in a lot of instances, it's difficult to say what reality is. Experimenters often read too much into their results. They are too anxious to obtain results that confirm their own theories.
The "action at a distance hypothesis" is one that comes to mind. The weight of opinion is that spin information is transmitted instantaneously from one particle to another over a sizable distance. A lot of the physicists will tell you that it's beyond doubt at this point, yet it seems to defy the Theory of Relativity.
On the other hand, the proof is merely statistical, and even then based upon theoretical assumptions that have not themselves been proven. In fact, we really don't even know what "spin" is. And as Einstein pointed out, it seems absurd. The experimenter's retort: Yes it's absurd, but nevertheless true.
I think I would be a little more hesitant to conclude that it's true, if I agreed that it is absurd, particularly when all I've got is statistical evidence to support it. It wasn't all that long ago that scientists finally concluded that cyclamates don't cause cancer, despite the 1970's claim that they were undeniably a significant cause of cancer.
Setterfield explains why a misinterpretation of redshift data leads astronomers to propose 'dark energy' and an 'increasing expansion'.
http://www.setterfield.org/AstronomicalDiscussion.htm#missingmass
But it still does not explain how or why Venus rotates in a different direction than the rest of the planets in our solar system rotate. We cannot explain a creation without a creator...but it appears we keep trying!
I see what you are saying now - excellent point - even Einstein called it “spooky action at a distance."
I just can believe in this yet....
Good post, sorry I misunderstood.
10,120 isn't that big a number really. The IRS might disagree, of course.
You're well ahead of me in the math department, and intuition isn't worth much unless it's well-informed. For what it's worth, I like the oscillating universe because it avoids the problem of the universe's being strictly a one-time affair. That definitely is counter-intuitive.
"cyclic model of the Universe, it expands and contracts repeatedly over timescales that make the 13.7 billion years that have passed since the Big Bang seem a mere blink."
This is not what makes time seem like a mere blink.
Time seeming short is due to the lifespan of man.
You wonder, then, why scientists have such a problem with religion. Why is one brand of incredulity better than another?
You know, that is exactly what I was thinking when reading this article. It speaks to an infinite universe. If scientists are fully capable of believing in the concept of the infinite, then why would the concept of an infinite creator be so hard for some of them to swallow? Infinite universe is a difficult concept to wrap one's mind around, just as is the concept of an infinite God. Why one would be an acceptable concept and the other not, is beyond my mortal comprehension.
>>
I just can believe in this yet.... <<
That was a type - should have said "I just CAN'T believe in this yet.... " - meaning instantaneous tyransmission of information without spacial warping.
"There is a theory which states that if ever anybody discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened."
--Douglas Adams
You might reasonably infer it could defy classical relativity theories in a three dimensional space. But that is actually an illusion due to our inability to directly perceive higher dimensions, just as flatlanders can't perceive the third dimension. Three-dimensional space at the quantum level doesn't seem to be what we're dealing with in this universe. If electromagnetic phenomena are viewed as ripples in higher-dimensional space, and photons by implication, then the two paired photons are part of the same thing and "right next to each other" in the higher dimension. The bizarre quantum phenomena actually do start to be consistent with common sense when you consider that they occur in a greater number of dimensions.
I guess I'm not really convinced by your arguments that 1) The evidence is only statistical (that is the nature of the quantum universe); 2) We don't know what "spin" is (It is a property of objects at the quantum level -- there will never be an explanation that it is "like ice cream" or something in our macro world); or 3) That some cyclamate studies were wrong (no comment).
"we need one ASAP called English for dummies........"
How about Politics for Dummies. Sorely needed.
As Clayton Williams once said; Just lay back and enjoy the ride.
Wouldn't a yo-yo universe violate the second law of thermodynamics? Basically, you'd have to figure that either the expanded or the contracted state would represent the state of max entropy, and there the whole deal would stay.
HA
Bizarro
"The "cosmological constant" either doesn't exist, or they have no idea what it is."
As further proof, the Cosmo...Constant is a variable.
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