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August 22, 2017
from
MessageToEagle Website
Earth is not unique...
There are
billions of other planets circling
billions of other stars in the Universe. Considering the vastness of
space, it's logical to think that there simple must be some
intelligent life out there.
So, where are those advanced
extraterrestrial species and why
haven't we detected them yet?
An astrophysicist suggests that species, like our own, go extinct
soon after attaining high levels of technology.
Daniel Whitmire, a retired astrophysicist who teaches
mathematics at the University of Arkansas, once thought the cosmic
silence indicated we as a species lagged far behind.
He is now of different
opinion.
"I taught astronomy
for 37 years," said Whitmire.
"I used to tell my
students that by statistics, we have to be the dumbest guys in
the galaxy. After all we have only been technological for about
100 years while other civilizations could be more
technologically advanced than us by millions or billions of
years."
Are We A
Typical Species In The Universe?
Today, Whitmire thinks we, humans are a typical species in
the Universe.
So, why did he change his
mind and what is his assumption based on?
By applying a statistical concept called the
principle of mediocrity - the idea
that in the absence of any evidence to the contrary we should
consider ourselves typical, rather than atypical - Whitmire
concluded that our species may not be as primitive as he previously
thought, but rather average.
The argument is based on two observations:
(He defines
"technological" as a biological species that has developed
electronic devices and can significantly alter the planet.)
The first observation seems obvious, but as Whitmire notes in his
paper (Implication
of Our Technological Species being First and Early),
researchers believe the Earth should be habitable for animal life at
least a billion years into the future.
Based on how long it took
proto-primates to evolve into a technological species, that leaves
enough time for it to happen again up to 23 times.
On that time scale, there could have been others before us, but
there's nothing in the geologic record to indicate we weren't the
first.
"We'd leave a heck of
a fingerprint if we disappeared overnight," Whitmire noted.
By Whitmire's definition
we became "technological" after the industrial revolution and the
invention of radio, or roughly 100 years ago.
According to the
principle of mediocrity, a bell curve of the ages of all extant
technological civilizations in the universe would put us in the
middle 95 percent.
In other words, technological civilizations that last millions of
years, or longer, would be highly atypical. Since we are first,
other typical technological civilizations should also be first.
The principle of
mediocrity allows no second acts.
The implication is that
once species become technological, they flame out and take the
biosphere with them.
"If we're not typical
then my initial observation would be correct," he said. "We
would be the dumbest guys in the galaxy by the numbers."
Whitmire's theory is very
interesting, but there are also other prominent scientists who have
debated how to classify
extraterrestrial civilizations.
In a seminal paper published in 1964 in the Journal of Soviet
Astronomy, Russian astrophysicist
Nicolai Kardashev theorized
that advanced civilizations must be grouped according to three
types:
Type I, II, and III,
which have mastered planetary, stellar and galactic forms of
energy, respectively.
He calculated that the energy consumption of these three types of
civilization would be separated by a factor of many billions.
"Although it is
impossible to predict the precise features of such advanced
civilizations, their broad outlines can be analyzed using the
laws of physics.
No matter how many
millions of years separate us from them, they still must obey
the iron laws of physics, which are now advanced enough to
explain everything from sub-atomic particles to the large-scale
structure of the universe, through a staggering 43 orders of
magnitude," Dr. Michio Kaku said.
Since we have never been
in contact with an advanced extraterrestrial race, it's really
impossible to predict the precise features of such advanced
civilizations.
References
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