One Big Bang, Or Many? 492
butterwise writes "From the Guardian Unlimited: 'The universe is at least 986 billion years older than physicists thought and is probably much older still, according to a radical new theory. The revolutionary study suggests that time did not begin with the big bang 14 billion years ago. This mammoth explosion which created all the matter we see around us, was just the most recent of many.'"
-1 for self-contradiction, -1 for lateness (Score:5, Informative)
From TFA (emphasis mine): And also from TFA (again, emphasis mine):
Now, I'm no cosmologist, but these two descriptions of the theory seem to be in conflict...does the matter in the universe come together in the Big Crunch, or does it fly off into space forever, replenished by subsequent Big Bang events?
If the Guardian Unlimited doesn't even know what the theory is proposing, why are they reporting it?
Fortunately, we needn't depend upon Guardian Unlimited for our cosmology news...Nature.com happens to have a much more informative article [nature.com] on the subject. What's especially amusing is that they've had this article since April 26th of 2002.
How is the Revolutionary? (Score:2, Informative)
See also... (Score:5, Informative)
Guardian misses the point (Score:4, Informative)
The cyclic model has been around for several years, and there is plenty I don't understand about it, but it is distinct from the old big bang-big crunch ideas. The "cycle" is the repeated collision between two sub-universes, called branes. We live in one of these sub-universes. Each collision resets our sub-universe with a new big bang... Our universe is constantly expanding; there is no crunch.
Importantly, the cyclic theory has detectable differences from the standard big bang scenario. For example, primordial gravity waves, detectable through their influence on the polarization of the cosmic microwave background, are present in the standard big bang scenario and absent here. Thus their possible detection by a future microwave experiment could rule out this theory.
The purpose of this new work is to argue that the cosmological constant (the factor which make the expansion of the universe accelerate) is naturally small and positive in the cyclic model. This is as we observe it. The standard big bang theory does not make a prediction for the size of the cosmological constant (it's just a parameter), while in string theories the expected size of the constant is vastly larger.
Steinhardt has many materials (including a cartoon movie of the brane collision) on his homepage [princeton.edu].
Cosmological constant survives the Big Crunch? (Score:4, Informative)
a) Might diminish over time, and
b) Might be able to survive a Big Crunch/Bang cycle, and
c) Seems to be smaller than it "should" be if the universe was created 14 billion years ago.
From these, they propose that:
d) The universe is actually much older and has gone through many Big Crunch/Bang cycles, allowing enough time for the CC to shrink to its current level.
However, I'd like to see some hard evidence for a), b), and c) before I accept that d) might be true.
Actual Article (Score:4, Informative)
Re:Wrong... read more closely (Score:3, Informative)
Here's some lazy links:
Big Bang [wikipedia.org]
Heat Death [wikipedia.org]
Re:-1 for self-contradiction, -1 for lateness (Score:2, Informative)
Actually, Hubble measured something called the redshift of the light from distant galaxies. He then ASSUMED and so has everybody since then, that this shift is caused by the doppler effect. There is increasing evidence that this assumption is wrong and that the redshift is caused by the changing over time of certain so called "constants" which affect the way atoms radiate electromagnetic energy when excited. The speed of light is greatly affected by the medium through which it propagates. If the nature of space changes, then the speed of light and related parameters will also change. Space is not some empty nothingness, but has some definitely measurable electric and magnetic properties. It is these properties that affect these "constants" and then indirectly these "constants".
NOTHING in the observable universe is constant, and there is no reason to assume that all of the so called "constants" are either. The math describing the observed properties of atoms contains terms which depend on the value of these "constants".
Observation, not some theories, show that the laws of physics operate uniformly in the entire known universe. Speculating about other dimensions and universes is not science. Are the laws of physics an innate property of the universe or were the laws here first and the universe obeys them? In our human context of course, we know that humans with minds were there first to make laws for other humans to be subject to. Is it then so far out to say that a superior mind was there first to formulate the laws of physics which the universe and everything therein is subject to?
Re:Better question... (Score:4, Informative)
Similarly, the centre of mass of the solar system is within the Sun, but still the Sun has a wobble due to its orbiting of the rest of the bodies in the system. That's more complex, of course, as with so many bodies, they tend to be at different points around it. Also the Sun is so much more massive than the other solar bodies as to render the effect essentially negligible.
The effect tends to be more noticeable in binary star systems as the two stars tend to be more closely matched in terms of mass. In that case, the centre of mass of the system is more nearly half-way between them. They both orbit something, but that something is a point of empty space.
Incidentally, this effect is how we've detected some extra-solar planets - particularly massive ones orbiting relatively small stars cause a noticeable wobble.
Talk about old "news" (Score:2, Informative)
From http://www.princeton.edu/pr/pwb/02/0506/0506-cycl
"Princeton University
April 25, 2002
New Theory Provides Alternative to Big Bang"
These guys, Tourok and Steinhardt, published this four years ago! News?