[extropy-chat] Drake Equation nitpicking

[Mike Lorrey]

--- Adrian Tymes <wingcat at pacbell.net> wrote:
> 
> >From http://en.wikipedia.org/wiki/Drake_equation :
> 
> > N = R* x fp x ne x fl x fi x fc x L
> > 
> > where:
> > 
> > N is the number of extraterrestrial civilizations in
> > our galaxy with which we might expect to be able to
> > communicate
> > 
> > and
> > 
> > R* is the rate of star formation in our galaxy
> > fp is the fraction of those stars which have planets
> > ne is average number of planets which can
> > potentially support life per star that has planets
> > fl is the fraction of the above which actually go on
> > to develop life
> > fi is the fraction of the above which actually go on
> > to develop intelligent life
> > fc is the fraction of the above which are willing
> > and able to communicate
> > L is the expected lifetime of such a civilization
> 
> Your points argue for high (near 1) fp and fl.  For
> this case, we're assuming an essentially indefinite L
> (L=~1, not infinity, since L is a fraction of the
> lifetime of the civilization's own universe), and fc
> refers to civilizations that expand through the
> universe and upload other sentient races rather than
> civilizations that communicate.  R*, we have pretty
> good data on too.
> 
> This leaves out ne (even if life flourishes everywhere
> it can flourish, that doesn't mean it can flourish on
> all planets), fi, and fc (which spike asserted to be
> 1, but gave no evidence for that assertion).

It also applies to all planets that *could* have supported life at some
time in the history of the universe. We know that both Venus and Mars
went through significant warm damp periods before settling in at
extreme ends of the green zone, for different reasons. Add in Europa,
Ganymede, and Titan and that is six possible worlds in one solar system
(and the possibility for jovian moons to harbor life means that any
star system with a jovian/superjovian in it could harbor life, no
matter how imperfect the orbit of the parent planet.) That the jovians
are outside the green zone is the only reason most of their moons are
not overtly life bearers. Any extrasolar jovian in its stars green zone
should be considered potentially life bearing to a degree of 1, for at
least one moon supporting an ecoysystem.

> 
> > > This assumes you know the physics of the world
> > > running the sim.  Maybe they can have perfectly
> > > randomness, and the mechanical non-randomness is
> > an
> > > artifact of the sim?
> > 
> > You are forgetting the turtles. More than one turtle
> > per universe means
> > a veritable plethora of turtlesque universes.
> 
> Sorry to call a spade a spade, but that's a
> non-sequiter.  Speaking in metaphor doesn't prove or
> disprove anything.  (Now, maybe if you clarified
> exactly what you meant by "turtles" - not just the old
> story about "it's turtles all the way down", but what
> you meant it to mean in this case...)

If one technological civilization exists at any time in the entire
history of each universe and develops sim tech, then odds are massively
in favor of the simulation argument.

We can prove this by modifying the Drake Equation. We can dispense with
the L variable, since we aren't interested in whether other
civilizations are co-existent with ours in this universe, wrt to this
thought experiment, and fc is gone because this isn't about
civilizations communicating across interstellar space, and we are
looking at number of civilizations per whole universe, not just per
galaxy:

N = R* x fp x ne x fl x fi x fc x ft x fs
 
where:
 
N is the number of extraterrestrial civilizations that exist at any
time in the history of our universe which we might expect to be able to
go posthuman and create simulated universes.

 and
 
 
 R* is the rate of star formation in our universe
 fp is the fraction of those stars which have planets 
 ne is average number of planets which can potentially support 
    life per star that has planets
 fl is the fraction of the above which actually go on to develop life
 fi is the fraction of the above which actually go on to develop
    intelligent life
 ft is the fraction of the above which survive to post-human
    equivalent technological development
 fs is the fraction of the above which develop and use universe
    simulation technologies to replicate their own past history
    or made-up histories.

(You can call this the Lorrey Equation ... ;)) It is quite clear that
if we are talking about a volume of space as huge as the entire
universe, then the odds of N exceeding 1 are extremely large. As soon
as N meets 0.5 (half of natural universes have one such civilization),
then the odds of us living in a simulated universe exceeds 50%. The
odds increase asymptotically as N approaches 1. Beyond N=1, you are
dealing with the mathematics of infinitely large probabilities, i.e.
sure things, tautologies.


=====
Mike Lorrey
Vice-Chair, 2nd District, Libertarian Party of NH
"Necessity is the plea for every infringement of human freedom.
It is the argument of tyrants; it is the creed of slaves."
                                      -William Pitt (1759-1806) 
Blog: http://www.xanga.com/home.aspx?user=Sadomikeyism


	
		
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