Seth Shostak is once again trying to
justify the work of SETI.
But seeing as that's his job, it's to be expected. He has to
perpetually defend the work of SETI to secure public support and
funding.
Shostak notes that there are four primary suggestions as to why SETI hasn’t found a signal:
1.
“You’re counting on the aliens using communication technology (radio,
light) that’s oh-so-last century. They will be far beyond this.”
2.
“If hi-tech societies or thinking machines were out there, they’d have
colonized the Galaxy by now. Clearly, we’re alone… lone… lone.”
3. “The aliens don’t want to communicate with us. Look at what we’re doing to the planet!”
4.
“You SETI types are just looking in the wrong places. We know where the
extraterrestrials are: on a planet in the Zeta Reticuli system.”
Reasons #1, #3 and & #4 are useless, but #2 is one I'm partial to. As I've
written before, the apparent dearth of ETI's in our galaxy is a disturbing observation.
In response to suggestion #2, Shostak writes:
This is, of course, an appeal to the Fermi Paradox,
which assumes that if sophisticated societies are common, they should
also be ubiquitous. Well, I just checked the parking lot outside the
Institute, and I see no large animals with long, prehensile noses. The
conclusion a la Fermi is that elephants don’t exist on this Earth,
right? After all, any putative pachyderms have had plenty of time to
get to my office, even if only a few of them are so inclined. To use
the Fermi Paradox as a reason for the lack of a SETI signal is to make
a very big extrapolation from a very local observation. Seems chancy to
me.
This is a surprisingly weak answer from Shostak who has
clearly misinterpreted the FP. No one is arguing that elephants should
be ubiquitous. If we thought, for whatever reason, that elephants
should occupy
specific ecospaces on Earth, but they don't, then that would be a sort
of observational conundrum much like the FP. I don't expect this, so I
don't see this as a problem.
On the other hand, our expectations
of AETI migratory behaviour and their potential megascale engineering
projects are a horse of a different colour. The FP is about the absence
of evidence when there should be evidence. And Shostak knows this;
otherwise he wouldn't be pointing his radio arrays at the sky. It would
be a convenience of the highest order if the first signs of ETI life
were to be discovered now.
Shostak and others are guilty of
grossly underestimating the characteristics of post-Singularity AETI's.
Those, like Shostak, who dismiss the FP betray a misunderstanding of
the potentials of
artificial superintelligence, radically advanced computing and such technological artifacts as
Von Neumann and
Bracewell
probes. And as usual, these dismissals fail to take into account the
extreme age of the universe and the huge expanse of time that has
preceded our own.
That said, Shostak may be (inadvertently) right about ETI localization. As
argued by
Cirkovic and Bradbury, AETI's may migrate from a biological habitable
zone to a technological habitable zone -- one more conducive to
megascale information processing projects like
matrioshka and
Jupiter Brains.
But
Shostak and SETI, I'm sure, aren't considering these types of
scenarios. My advice to SETI: keep on listening, but don't expect to
hear anything.