Saturday, January 16, 2010

The Great Silence

Are we the only one who looks up at the stars and wonder, is there anything, is there anybody else out there? It is perhaps the greatest question that we can ask of the universe. As we know, today, we are the only globally known civilization with advanced technology and this is somewhat unusual among many astronomers most of them take the view that life is common throughout the galaxy and that Intelligent life is common.

Our sun is one of billions of stars in the milky way galaxy and our galaxy is one of hundreds of billions, may be a trillion in the known universe. It would be the height of presumption to think that we are the only living being in this enormous immensity. A simple life can be incredibly widespread. Wherever there’s water on Earth in liquid form, at a temperature within a reasonable range life manages to seek out an existence, but the probability of that life evolving as an intelligent life and becoming a technologically advanced civilizing might be rare. But it is always possible as it happened here on Earth virtually the instant that conditions were suitable.

We’ve got billions of years of evolution, going from single cells on the Earth to intelligent life, but that hasn’t been a progressive evolution, there have been fits and starts, there have been great periods of evolution and then a break. One of the biggest breaks happened 65 million years ago when a meteorite impacted the Earth and wiped out most species. At that particular time the dominant species, the dinosaurs, were wiped out. Without that impact perhaps intelligent life might not have emerged on the Earth, or it might be completely different. There are number of factors which helped intelligent life on earth. We got a very stable environment for a very long time, the plate tectonic system recycles the CO2, helps to regulate the temperature, we have a large moon which helped to stabilize the rotation axis of earth, huge amount of water, Oxygen, Gravity, distance from Sun etc... But the same pattern or the environment which triggered or helped the evolution of intelligent life on earth may not happen in any other places of the universe.

One of the problems with trying to define and understand ‘Intelligence’ is that we only look at our own patterns of behaviors. It’s possible that there are different types of intelligences that we don’t understand, that we don’t appreciate, something which is so completely beyond our ken that we wouldn’t even recognize it as intelligence when we see it. Ant colonies, bee colonies have a certain amount of intelligence, we perhaps say, ok, they’re intelligent in one way but not in another. Remember, Terrestrial life is embedded in the cosmic web, and it is common throughout the Universe. The challenge that we are facing today is to move this speculation to a fact.

Using some simple math we can conclude that if technological civilizations were common then the galaxy should be fully colonized (assuming only standard physics). Contact should be completely inevitable. Since we cannot readily detect evidence of technological civilizations, there is a paradox here. Any civilization with a modest amount of rocket technology could rapidly colonize the entire Galaxy. Within ten million years, every star system could be brought under the wing of empire. Ten million years may sound long, but in fact it's quite short compared with the age of the Galaxy, which is roughly ten thousand million years. Colonization of the Milky Way should be a quick exercise.

However, we see no signs of galactic federation. Why does the cosmos look so untouched and unconquered? What is keeping advanced extraterrestrials from claiming every star system in sight? This paradoxical failure is sometimes called "The Great Silence". The Great Silence suggests that space traveling technological civilizations is extremely rare (or very discrete). There have been a number of explanations for why such civilizations might be rare. Let me list out some here, You can choose the one you like.

  • Technologically advanced civilizations may rarely form. We live in a very dangerous universe. One big gamma-ray buster can sterilize a galaxy. Supernovae are common, and they sterilize a pretty good chunk of space every time they blow.
  • Technological civilizations may be very short-lived, they may universally fail. They might play with some dangerous nuclear toys during the development stage and destroy them self.
  • All technological civilizations may lose interest in exploration quickly and comprehensively. One possible explanation is that interstellar travel is just too costly.
  • The Earth may be in a kind of 'Galactic Quarantine'. We may be, being shielded from rogue civilizations by other races intent on protecting us, until we reach the required level of maturity they will wait for First Contact.
  • The aliens may not wish to contact the populace in general. They may be simply interested in studying us and not opening full diplomatic relations.
  • God created the world in 7 days, and he made it for man alone. He didn't want anyone else in our galaxy, maybe in the entire universe.

Any of them in the above might be true or Nonetheless. Will all the aliens find colonization too costly? Is all the places in the Universe is dangerous in all time? Are we so special that someone has really gone to the trouble to put us behind invisible bars? We have no answers.


  1. Interesting to read..
    will be more interesting if we get answer for the last few questions :)

  2. sure இரவுப்பறவை, we have a long way to go.

  3. Uve def got a knack to convince....
    amazing write up...
    considering going professional??
    I take half the shares :P

  4. Good going...

    I agree on one point majorly which says

    "One of the problems with trying to define and understand ‘Intelligence’ is that we only look at our own patterns of behaviors."

    May be to define what is intelligence is a bigger challenge than finding intelligent life forms in alien planets.