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WMAP third data release, precision cosmology and cosmic coincidences
dilo
post Mar 13 2008, 02:16 AM
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Nobody highlighted it, but the 5-year WMAP results were published on March,07 and results are stunning:

I long awaited this moment and, looking to results, we definitely entered in the "precision cosmology" age... (frankly, this goes well behind my hopes to see such accomplishments in my lifetime! smile.gif ).

Between the many foundamental determinations and refinements (which I hope will be discussed here), the most impressive result in terms of precision is the universe age, now known with less than 1% uncertain after joining WMAP estimation with other independent measurements:
t0 = 13.73 + 0.12 Gyr

It seems that, at this point, we know the age of universe with a relative precision comparable to Solar system age [from Wikipedia]:
tss = 4.53 to 4.58 Gy

Now, about these two ages, after previous WMAP release I was already disappointed by an intriguing coincidence, now confirmed by new estimation:
t0 / tss = 3.014 + 0,043

So, within uncertain range, the ratio "is" exactly 3!
I know that, to many, this is only a coincidence. Otherwise it would require that we live in a very special moment...and place! rolleyes.gif
Even if a little bit mistic, this approach isn't new in the cosmology: think about anthropic principle and large numbers coincidences!

Anybody wants to accept such provocation? unsure.gif


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centsworth_II
post Mar 13 2008, 02:40 AM
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QUOTE (dilo @ Mar 12 2008, 10:16 PM) *
So, within uncertain range, the ratio "is" exactly 3!
I know that, to many, this is only a coincidence.

Since our solar system -- and we -- are made of "star stuff", at least one
generation of stars had to form, grow old, and die before the creation of
our solar system was even a possibility. So there is a minumum age for
the universe before a second generation solar system like ours could be
formed. Add to that the average time for intelligent life to evolve and it's
probably not that surprising that the numbers add up like they do.
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dilo
post Mar 13 2008, 02:28 PM
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Centsworth, your considerations are reasonable; however, you're assuming that 1st generation stars have the same (or half) Sun lifespan and that average time for intelligent life to evolve is always the same than Earth. I think that these assumptions are "a posteriori" and cannot be sufficient to explain such exact ratio...


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centsworth_II
post Mar 13 2008, 03:42 PM
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To make your ratio special, either we would need to be the only intelligence
in the universe, or every intelligence in the universe would need to find that
the same ratio holds for them. Otherwise the ratio in our case would just fall
in a necessary range, say, arbitrarliy, between 1.5 and 4, and just happens
to be 3. There may be reasons for the arbitrary range I give being even
tighter, I don't know. I'm just saying that it's not surprising that the ratio is
around 3, and the odds are probably not very great against it being exactly 3.

Do you think we are alone in the universe, or do you think that this exact
ratio holds for every planetary system harboring intelligence?
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Guest_PhilCo126_*
post Mar 13 2008, 05:16 PM
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Guests






Don't forget the Universe exists because we observe it wink.gif
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centsworth_II
post Mar 13 2008, 06:13 PM
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It certainly exists as a concept in the human mind because we observe it.
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dilo
post Mar 13 2008, 06:42 PM
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Good anthropic points...

QUOTE (centsworth_II @ Mar 13 2008, 04:42 PM) *
Do you think we are alone in the universe, or do you think that this exact ratio holds for every planetary system harboring intelligence?

Good question, but I don't have an answer! Probably, we are talking of 2 different questions.
If we aren't alone, the ratio for other civilization reasonably falls in the range you indicate... however, I was impressed by the proximity to an integer number, a coincidence that cannot be universally explained, unless "someone" wants to tell us something! ph34r.gif
It is the same sensation I feel each time I think about equivalence of Moon and Sun apparent size in our sky, a peculiar situation that never happens in other places of our Solar System (I verified this also considering moons seen from other moons around giant planets!).
Ok, I know this is a very dangerous terrain, where science, numerology and religion collide. I do not want to ignite such debate, personally I'm not religious but a part of me still strongly intrigued by these mysterious, funny facts, like the great P.M.Dirac was amazed by "big numbers" coincidences.


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centsworth_II
post Mar 13 2008, 07:52 PM
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QUOTE (dilo @ Mar 13 2008, 02:42 PM) *
...I was impressed by the proximity to an integer number, a coincidence that
cannot be universally explained, unless "someone" wants to tell us something!

The ratio of three is based on two numbers that are subject to change, particularly
the age of the universe. Even if the numbers hold, someone doing the same calculation
200,000 years from now will get a ratio of 2.93. Not so remarkable.
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dilo
post Mar 14 2008, 04:08 AM
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This is the reason why I said in my first post "we live in a special time and place"...
note: your figure is referred to 200 Myr from now. Exact ratio 3.00 is centered about 33 Myr in the future, but actual uncertain in this value is equivalent to a range of +100Myr!


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centsworth_II
post Mar 14 2008, 05:33 AM
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Another thing to look at:

Before the evolution of intelligent life on Earth, there was some
3 billion years of single cell life. Then several periods of a hundred
million years or so each where various types of life predominated until
some global event changed the balance. It seems to me that the long
history leading up to our "special time" is ripe with opportunity for some
change in fate (one less or more killer meteor strike) to have thrown the
timing off. That the timing of the appearance of life on Earth able to
calculate your ratio could so easily have been changed by such a
simple, concrete process as the frequency of asteroid strikes on
the Earth seems to be proof that it is in fact a coincidence.
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dilo
post Mar 14 2008, 02:43 PM
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...sure, unless you believe that asteroid are piloted by someone! wink.gif


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djellison
post Mar 14 2008, 03:21 PM
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QUOTE (dilo @ Mar 13 2008, 06:42 PM) *
I was impressed by the proximity to an integer number,


Why?
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ngunn
post Mar 14 2008, 03:51 PM
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230 million years ago the ratio was exactly pi, but the message was completely lost on them:
http://www.graaffreinet.co.za/pages/fossils3.html
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centsworth_II
post Mar 14 2008, 03:57 PM
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And concerning the +/-.043 error for the ratio:
That gives a .086 (almost .1) range around the
calculated value. To me, it looks like, just randomly,
there is almost a one in ten chance that a value will
fall within the range of error of an integer.
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JRehling
post Mar 14 2008, 06:46 PM
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I also noticed this ratio. But I also recall when other estimates of the age of the universe indicated another ratio.

The key to determining how significant a coincidence is is to tally all of what fraction of the range of possibilities do you consider special? If someone 400 years ago had predicted that the ratio would be 3:1, and it turned out to be so, that would be remarkable. But nobody did -- we're postdicting. We'd be just as impressed if it were 2:1 or 4:1.

And, how many such ratios may exist? For all significant ages, if there are n of them, there are n^2 - n combinations that can result in ratios. And why just ages; why not masses, or distances? Perhaps there is some magic number out there in terms of how many AU across the galaxy is, or how the escape velocity of Earth, or the Sun, or the galaxy, relates to the speed of light. Or if the period of the solar system around the galactic center were some even fraction of the age of the Earth or the universe.

Out of at least hundreds of such ratios we could conjure up, is it remarkable if one of them is nearly (to within a few percent) an integer? Not at all.

It might seem remarkable if we gained more digits of accuracy and the number seemed fixed at 3.000...

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