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ToSeek
2004-May-20, 03:04 PM
Cosmos 'a billion years older' (http://news.bbc.co.uk/1/hi/sci/tech/3732157.stm)

Universe reportedly deeply offended at scientists so callously revealing its true age.

Russ
2004-May-20, 03:39 PM
Cosmos 'a billion years older' (http://news.bbc.co.uk/1/hi/sci/tech/3732157.stm)

Universe reportedly deeply offended at scientists so callously revealing its true age.
Oh, the fickle wench! What loss there may be in the light of such divulgance! What light falleth from yon window of truth? Why lament the beauty of the ages?

An interesting article ToSeek! They don't say what makes them think the reaction rate has been consistant throughout the ages. Given the recient discovery of the accellerating universe, it could be that this reaction ran slower or faster in times gone by. :)

dgruss23
2004-May-20, 03:41 PM
WMAP results give 13.7 billion years. The error bars on that estimate don't overlap the new stellar ages. I wonder how the parameters will have to be adjusted to bump things up to 14.7 billion years?

Spaceman Spiff
2004-May-20, 05:26 PM
Cosmos 'a billion years older' (http://news.bbc.co.uk/1/hi/sci/tech/3732157.stm)

Universe reportedly deeply offended at scientists so callously revealing its true age.

This paper (http://arxiv.org/PS_cache/astro-ph/pdf/0312/0312559.pdf)is a bit more conservative: the oldest MW globular cluster stars are ~0.7 billion years older. It has been published in PhysLetterB.

I don't know which error bars dgruss23 is referring to, but even if the "internal" 1-sigma error bar of the age derived by WMAP is small (1%), that for globular clusters is about 1 billion years. This recent paper (http://arxiv.org/abs/astro-ph0307016) (that didn't take into account these new nuclear reaction rates) says that when you throw the kitchen sink into the simulations, they find that the oldest globular clusters in the MW have ages of 13.4 +/-0.8 +/-0.6 billion years. The first uncertainty is the internal random error, the second tries to account for systematic errors (an important nuclear reaction rate, for instance, or a systematic goof to GC distances). Also, the guys in the first paper just took this new nuclear reaction rate and placed it into today's state of the art stellar evolution codes to derive their result. So one piece of physics has been improved. What else might be missing? This is called iteration, and as better data and improved physics come to the fore, the numbers will converge with ever smaller error bars.

Also, don't take the above to mean that the 13.7 Gyr +/-1% number from WMAP is in any way, shape or form the final word, and all the other observations will have to somehow conform to it. No way, no how. Refinements in WMAP's data over time and those that will come from still more sensitive instruments in the future will shove that number around, too. Convergence from multiple, independent observations and physics will point us in the right direction and/or open the door to new understandings of nature's workings.

George
2004-May-20, 05:51 PM
[Shoot. :-? Ya'll are way too addictive! I'm trying to keep my mouth shut and learn (obviously, with no success on either point). I feel like a fan jumping onto a pro baseball field (albeit clothed) to join in the fun.]

If we have been accelerating now for about 6 billion years, wouldn't this change the Hubble Constant to a Hubble Variable? If so, wouldn't this yield less redshift of the CMB (z=1089) unless the universe was older afterall? #-o

Spaceman Spiff
2004-May-21, 06:13 PM
[Shoot. :-? Ya'll are way too addictive! I'm trying to keep my mouth shut and learn (obviously, with no success on either point). I feel like a fan jumping onto a pro baseball field (albeit clothed) to join in the fun.]

If we have been accelerating now for about 6 billion years, wouldn't this change the Hubble Constant to a Hubble Variable? If so, wouldn't this yield less redshift of the CMB (z=1089) unless the universe was older afterall? #-o

The Hubble "Constant" has been expected to be a "variable" for more than 50 years. This is taken into account in the expansionary cosmology.
H is a function of z, and this is what the Type 1a supernova guys are measuring (indirectly; they're actually measuring what's called the "luminosity distance").

George
2004-May-21, 10:14 PM
[Shoot. :-? Ya'll are way too addictive! I'm trying to keep my mouth shut and learn (obviously, with no success on either point). I feel like a fan jumping onto a pro baseball field (albeit clothed) to join in the fun.]

If we have been accelerating now for about 6 billion years, wouldn't this change the Hubble Constant to a Hubble Variable? If so, wouldn't this yield less redshift of the CMB (z=1089) unless the universe was older afterall? #-o

The Hubble "Constant" has been expected to be a "variable" for more than 50 years. This is taken into account in the expansionary cosmology.
H is a function of z, and this is what the Type 1a supernova guys are measuring (indirectly; they're actually measuring what's called the "luminosity distance").

That makes sense. I get the impression that slight positive curvature (expansion) has been the favored view in the past, but that came after the zero curvature view as established with Einstein's Cosmological Constant. As a result, I have viewed the Hubble Constant as an average rate from the time between recombination and now. Is this the correct way to see it?

It would be helpful if I could get a better handle on separating the motion of space itself from the motion of matter within space. Is the expansion rate of space subject to gravitational issues and/or dark energy?

I am inclined to see matter (i.e. galaxies) succumbing to motion as a result from the two forces - gravitational and dark energy (Higgs Field?). Gravity, initially, causing deceleration since recombination (the original "Orange Flash") but dark energy reversing the acceleration vector outward. If so, I suppose a fairly simple equation could be established once more data is acquired which would, more accurately, determine a galaxy's position relative to us.

I still have a hunch these variables will allow for an older universe as the Hubble Constant might turn out to be smaller around mid-time atb. Do you see any indication of this? Is supernova data very accurate yet at these distances?