The
Fermi Paradox! Who the heck is Fermi?
EnricoFermi (1901 –1954) was an Italian born physicist who pioneered the development
of controlled nuclear fission. His name has been attached to many important
things – Fermi-Dirac quantum statistics for one, for which he got the Nobel
Prize in 1936. In fact the entire visible universe is made up of Fermions and
Bosons. How’s that for putting your stamp on things? He had the job of creating
the first controlled nuclear power pile under the stadium stands at the
University of Chicago in 1942. The principal nuclear particle research facility
of the United States, the Fermi Lab near Chicago, is named in his honor. Enough
of that: he was very famous and really a very nice guy. Although he didn’t live
very long he got started early and got a lot done in his short life.
A very
important facet of his brilliant career began when he joined the group at Los
Alamos to work on the development of the atomic bomb in 1943. Three other
scientists, well known to most of us, were also hard at work at Los Alamos and
were involved at the birth of the Fermi Paradox some years later. These three
men were Edward Teller of H-Bomb fame; Emil Konopinski, nuclear physicist; and
our own beloved Herb York, variously first head of the Lawrence Livermore Labs,
founding Chancellor of UCSD, professor of physics, and Ambassador to Geneva to
negotiate the Nuclear Test Ban Treaty. The ethnic origins of these four give a
clue as to why America does science so well: Fermi, Italian; Teller, Hungarian;
Konopinski, Polish; and York, Mohawk Indian. We remember three of these men
with great admiration but Edward Teller fell from grace in the physics
community after he threw J. Robert Oppenheimer under the bus at a Senate
hearing in 1954, kick starting the McCarthy witch hunting era.
The
Paradox – One day in 1950 at Los Alamos these four were on their way to lunch.
Without preamble Fermi spoke up, “Where are they?” The others knew
immediately what he was referring to. They had discussed it before. It seems
the Universe is vast, as many as 400 billion stars in just our own Milky Way
galaxy and there are hundreds of billions more galaxies out there. It seemed
inconceivable that not only life but intelligent life must have appeared many
times over among these almost uncountable stars. Back in 1950 we had no evidence
of planets around distant stars as we have today but scientists assumed that
processes similar to those that created our own planetary system must exist
around other stars. And indeed we now know that nearly all stars have planetary
systems.
Though
the average citizen has probably not paid much attention to these three little
words, they have rattled around the scientific and speculative community for
the nearly seven decades. Literally thousands of scientific and
quasi-scientific papers have been written on the subject. The SETI (Search for
Extra Terrestrial Intelligence) project has been on going for a very long time.
Some agree it’s a good idea; others disagree. That’s not the point.
Considerable astronomical resources and brainpower have been searching diligently
for evidence of ET, and all these erudite scientists have been wondering ‘where
are they’ and why haven’t we found any evidence of their presence.
Here
are some of the factors in the question. The universe is about 13.8 billion
years old. Life has been on earth only about one billion years and the human
species, as we know it, has been around for less than a million. One has to
realize that this is but a momentary blink in the time scale of the existence
of the universe. For life to have appeared, however unlikely that might be assumed,
it must have appeared literally millions if not billions of times on the
planets of suitable stars in our own galaxy. And we are indeed finding today
that there are a great many suitable stars. Keep in mind, if we assume a very
low probability of intelligent life, maybe on just a mere million planets, these
million planets having some sort of intelligent life may seem a lot, but it is only 0.00025% of the total number.
Life may exist in literally billions of planetary systems just here in the
Milky Way, intelligent life on just a tiny fraction – only a million.
We
being around here at all to ponder these interesting speculations is the result
of a pretty low probability event, the meteor strike in Mexico, the Chicxulub impactor, which wiped out the dinosaurs. This was a highly unlikely occurrence
that gave mammals a chance to thrive and for humans to evolve. We also tend to
forget that the age of dinosaurs was a very very long period, far longer than
the period that mammals have had since. Maybe a species of dinosaurs such as
the velociraptor would have evolved into a truly sentient and technically
competent species. What we know about crows today, a close relative of the
dinosaurs, and their intelligence give us cause to think it could happen. We’ll
never know.
The
next important factors are the distance between stars and the velocity of
light, the ultimate maximum speed. Like it or not, Einstein’s limit on velocity
of anything is probably the most certain fact in the realm of physics.
Distances between stars are measured in light-years, how far light can travel
in one year. The nearest stars are of the order of a few light years distant
but most of what we see in the sky at night are thousands of light-years away.
Sending any material object from one star to another is a prodigiously
difficult undertaking. Even achieving 1% of the speed of light is hard to
conceive. That would certainly stand in the way of much traffic between the
stars.
Scientists
who are concerned with evolution and the development of civilizations, etc.
have opined that a sentient race may arise and become extinct in a blink of
time – a few million years at most. This would mean that having two or more
technically adept civilizations coexisting within any sort of reach of each
other might be highly unlikely.
Since
the invention of lasers the early radio telescope efforts of SETI (which are
still underway however) may be totally obsolete. At one time scientists worried
that the leakage of I Love Lucy into
interstellar space would alert some malevolent ETs to our presence and result
in our obliteration. Not to worry; recent calculations seem to confirm that
there isn’t enough energy in such broadcasts to be detected outside our local
region. Some assume that very advanced races would communicate using
point-to-point means employing, not radio, but light. We might be looking with
the wrong technology. But the leakage of laser radiation between the stars is highly unlikely. We use lasers for precisely the reason of economy - all the radiation gets to its intended goal. Setting up laser SETI systems would be a fool's errand.
Other
theories abound. One says we are being quarantined because of our warlike
nature; another, natural evolution removes interest for interstellar exchanges,
and so on.
There
is a considerable community of serious scientists that say that it is dangerous
to try to make contact with possible interstellar civilizations whose motives
we could not possible guess. Best left alone!
All of
these ideas and efforts leave out what I like to think of as the elephant in
the living room that no one seems to have noticed – Artificial Intelligence –
Machines. Surely no one has missed the recent news that 1000 scientists have signed
a letter protesting the development of autonomous weaponry, really a first step
towards AI. In a recent conversation with a well known author and scientist I
opined that machine evolution could advance very rapidly once they achieve any
sort of sentience, achieving super intelligence in a hundred years. His
response was, “A hundred days, not a hundred years.” Why would we assume a
sentient machine would be a nice guy like Star Trek’s Data? Maybe she (?) would
be more like Ava of the recent British thriller, Ex Machina.
Here’s
a thought. Maybe the universe is populated by machines that neither love nor
hate us and, at the moment, are not in need of the resources represented by our
planet and us. Have a nice day.
