
Re: BIG NUMBERS #1
Posted:
Apr 9, 2002 12:49 PM


>What I'd really like to do is calculate the probability >that NO particle or atom with a finite halflife would decay >during the 15 billion years of our universe's time span. When >you factor in all those elementary particles whose halflives >are on the order of 10^(24) sec, I imagine this will produce >produce a superlargeinitstinyness number. It might even go >beyond my current record for something of physical significance, >the 10^(10^166) count of the number of possible universes in an >(oversimplified) manyuniverses framework. Does anyone have a >suggestion on how to estimate something like this? This would >be an "alternate history" in which there were no atomic bombs, >no Carbon14 dating, no (interesting) cloud chamber results, >no radioactivity, etc. Of course, it's also very likely that >there'd be no stars, no people, . . . > >Dave L. Renfro
First try:
Do a density calculation of the universe at, say 10^10 seconds, get the approximate radius from inflation, use this to estimate the number of vector bosons (mass around 80GeV), then use the 10^25 second halflife to estimate your result.
This actually does assume the decay of Higgs particles, as well as some supersymmetric particles, but it should give an amusing number.
Not much would exist in such a universejust a mass of undecayed bosons.
Dan Grubb

