On Sat, Jan 18, 2014 at 12:17 AM, meekerdb <meeke...@verizon.net> wrote:
> On 1/17/2014 8:35 PM, Jason Resch wrote: > > > > > On Fri, Jan 17, 2014 at 9:55 PM, meekerdb <meeke...@verizon.net> wrote: > >> On 1/17/2014 3:13 PM, LizR wrote: >> >> Indeed it would be very strange, perhaps verging on miraculous. I believe >> just the nuclear resonance discovered by Hoyle alone is already incredibly >> fine tuned, after which we have the amazing properties of carbon and water, >> and the cosmological flatness and god (ahem) knows what else. >> >> >> Hoyle predicted that there had to be an excited state of C^12 at 7.7Mev >> in order to produce the observed abundance of carbon. It was observed at >> 7.656Mev. But it was shown by Livio, M. et al. (1989). "The Anthropic >> Significance of the Existence of an Excited State of C12." Nature 340, >> 281-284, that essentially the same amount would be produced by a resonance >> between 7.596Mev and 7.716Mev. Even more would be produced with a lower >> resonance down to 7.3367Mev, the difference between Be^8 + He^4 and C^12. >> And carbon sufficient for life would be produced up to 7.933Mev. Whether >> an 8% range is fine-tuned or not, I don't think it's "incredibly >> fine-tuned". >> > > It becomes incredible when one considers the 10 - 20 other parameters > that similarly had to be within a narrow range. > > > What are they? I've seen a lot of questionable claims of 'fine-tuning'. > One problem is that 'narrow range' is ill defined. If there is no natural > limit on a variable, then any range is 'narrow' relative to *+*inf. > Tegmark provides a good list in his M.U.H. paper. I've also provided a number to you before. I'll repeat some here: - The atomic masses of the lightest elements was such that there was the mass-5 roadblock. Without it, and the and the instability of beryllium, all hydrogen would have fused in the first few minutes following the big bang. - The expansion rate of the big bang was fast enough that everything didn't fall into black holes but slow enough that gas was able to coalesce into stars and galaxies - Galaxies were just the right size that stars are far enough apart to enable stable solar systems (near collisions between stars is rare) but aren't so far apart that second and third generation stars could not form from previous generations of stars - Gravity is strong enough to hold stars together, but not so strong that all stars exhaust all their fuel in millions of years rather than billions of years - Without neutrinos, nearly all of the heavy elements necessary for life would be swallowed up when a heavy star collapses into a black hole - Had the electromagnetic force had been weaker than the strong force, then there would be no element but hydrogen - Had the strong force been 11% weaker than it is, there could be no deuterium (a necessary step in the process of stellar fusion) - Had the strong force been 3.7% stronger, all hydrogen would have converted to helium in the first few minutes - Had neutrons been less massive than protons, then protons could decay into neurons and Hydrogen would be unstable - Had neutrons and protons been within less than one electron mass of each other, then neither could decay, and all hydrogen would have converted to helium in the first few minutes Jason -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
