[extropy-chat] Drake Equation nit picking

[Amara Graps]

>Michael Crichton had some interesting things to say about the
>Drake Equation:

>"This serious-looking equation gave SETI an serious footing as a
>legitimate intellectual inquiry. The problem, of course, is that
>none of the terms can be known, and most cannot even be
>estimated. The only way to work the equation is to fill in with
>guesses. And guesses-just so we're clear-are merely expressions
>of prejudice. Nor can there be "informed guesses." If you need to
>state how many planets with life choose to communicate, there is
>simply no way to make an informed guess. It's simply prejudice."

>"As a result, the Drake equation can have any value from
>"billions and billions" to zero. An expression that can mean
>anything means nothing. Speaking precisely, the Drake equation
>is literally meaningless, and has nothing to do with science."

With all due respect to Michael Crichton, is he working in the
field where these scientists are working?

I suggest for Crichton the chapter : Intelligence on Earth and in
the Universe in Frank Shu's book _The Physical Universe_,
University Science Books, 1982. It's old, but the science
grounding is very good. The 'serious-looking' equation is a good
first approximation or model, to quantify the problem. Yes, it is
true that many of the numbers that researchers use in the
equation are their best guesses, but it is what we know
presently, and that doesn't mean that it is not science.

The science grounding is not only good, it is one of the best
topics to use in a basic astronomy class, or even a general
science course because it is multidisciplinary, and most young
people love it, and it spurs their curiousity and zest for
learning especially in the sciences. This Drake Equation topic is
given in the texts that I use for my own astronomy course, and 
you can see it embedded in the Astronomical Society of the
Pacific's "Project Astro":

http://www.astrosociety.org/education/family/resources/seti.html

I don't think that any SETI researcher has claimed that it is the
latest and greatest model. However, I do think that the Drake
Equation has become such a common base for researchers over the
last 40 years with which to talk to each other, that they use it,
or parts of it automatically. This equation appears constantly in
my casual browsing of the field and when I am at conferences. Not
as the best model, but as a collection of useful concepts.

For example, in _Life in the Univese_ by Dirk Shulze-Makuch and
Louis N. Irwin, Springer Verlag, 2004, the preface contains this
paragraph:

"This book embraces the conviction that life is not restricted to
our planet. We accept as plausible that, with 10^11 stars in our
galaxy, and each frequency component of the Drake Equation
conservatively set to 0.01, there may be 10^5 abodes for life in
our galaxy alone. Tnad ther are billions of galaxies. Thile
computations such as these are cebatable (if unresolvable at the
present time), we do not take issue with their general
conclusion. Rather, the objective of this book is to analyze in
critical scientific detail the fundamental, commonly-hel
assumptions about life beyond Earth - particularly those relating
to the probably cosmic preference for carbon-based life, the
overwhelming focus on water as the prefferred solvent for life,
and the relative merits of different forms of energy for the
sustenance of life. Whiel we do assume that extraterrestrial life
exists, we take nothing about its nature for granted."

Another example:
New Scientist last August 14, 2004, wrote of Frank Drake giving a
talk at Harvard about SETI, where he stated that we need to find
intelligent beings soon, because cable TV does not leak signals
into space, and traditional broadcast antennas are being used
less (so then his fc term will be less).

Another example:
At COSPAR in Paris last July, I rather randomly ran into a poster
titled: "Number of Planets with Life in the Galactic Habitable
Zone Deduced by the Modified Drake Equation"

For me, this equation pops up 'everywhere'.

Amara