A consequence of accelerated expansion

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[EBTX]: If the Hubble constant isn't constant and is rather increasing (as in 'accelerated expansion' models) ... then ... by our present means of reckoning ... the earth could be seen as younger than the universe.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

The Earth is much younger than the universe even with a constant Hubble value. If is "only" about 4.6 billion years old (the age of the oldest Moon rocks and meteorites). Our Galaxy too appears to be younger than the universe by several billion years. -|Tom|-

OOPS ... I meant to say OLDER not "younger" ... I must have stayed up too late ;o)

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[EBTX]: If the Hubble constant isn't constant and is rather increasing (as in 'accelerated expansion' models) ... then ... by our present means of reckoning ... the earth could be seen as OLDER (not younger) than the universe.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[EBTX]: If the Hubble constant isn't constant and is rather increasing (as in 'accelerated expansion' models) ... then ... by our present means of reckoning ... the earth could be seen as OLDER (not younger) than the universe.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

If the expansion is accelerating, then the expansion is faster today, and the Hubble constant is greater today, than in the past. That would make the entire BB universe older than we previously inferred. Earth's age is measured by radiometric dating methods that have nothing to do with expansion, and would not be changed by whatever we learn about expansion. -|Tom|-

Of course it wouldn't change the Earth's age. The curiosity is that it would "appear" to be older than the universe by big bang measurement. If the Hubble constant were some day 50000 kilometers per second per megaparsec (instead of just 50) ... the age of the universe would be measured as about 20 million years (it would appear to have begun in the "primordial explosion" just 20 million years ago).

Then people would look at the other evidence (as you say) and conclude that it was in contradiction with the big bang hypothesis. This is an exageration but it is the same in principle for smaller scale increases in the Hubble constant. Thus, clusters of stars might appear to be older than the universe falsifying the big bang or at least requiring another retrenchment.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[EBTX]: clusters of stars might appear to be older than the universe falsifying the big bang or at least requiring another retrenchment.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

We already have that situation. Certain globular clusters appear to be up to 18 billion years old, whereas the BB universe is now set at about 13.7 billion years. It's an item on our list of the top 30 problems with the Big Bang, as published in MRB. -|Tom|-

And ...

If you fraction the Hubble constant, i.e. to 1/2, 1/4, 1/100 ... assuming that the present 50 k/s/m was less in the past ... you get ever older universes (inversely proportional to the fraction). So when the Hubble constant was .5 k/s/m ... the universe must have appeared to be 100 x 13.7 = 1.37 trillion years old !!

To me, a real "accelerated expansion" appears to rule out big bang type time measurements as not logically valid within the confines of the standard model. One could only estimate the age of the universe in this way ... IF ... the constant were indeed constant.