Thursday, May 13, 2010

Are We Alone in the Universe?

What is the chance there is carbon based life somewhere out there in that vast universe? Human life as advanced, or more advanced than we are, and that could some day (soon?) visit us?

Is our existance based on chance, or design?

Many think that in the billions of years the universe has existed, the chances are that other carbon based intelligent life forms must have come into existence and evolved into civilizations the way that we humans have. The universe, so old and vast MUST be repleat with a variety of life forms, some of which may have even visited earth from time to time in the past millenia.

One theory, or principle may disagree with that. This group of theories is outlined in far greater detail and precision in John D Barrow and Frank Tipler's excellent tome The Anthropic Cosmological Principle (shown at left) ISBN 0-19-282147-4.

Let's consider, at least, the idea that it would be impossible for there to exist in this universe another carbon based life form even slightly more advanced than our own. That we, the humans of earth, are the most cutting edge thing going in the area of advanced civilizations. Scary? You bet, but how could that be?

Consider please, how old is humankind? Depending on who you talk to, the modern answer for the age of humans is in the ball park of 2.5 million years old.

So let's say that THAT is about average for a carbon based life form to evolve from a pre human into an intelligent, modern form. Add to that, the average of about 500 million years for life to evolve from a basic, complex life form, into the first fishes and eventually into human form.

So, a planet would have to be AT LEAST 500 million years old, right? Right, but there is more...

To begin with, it would take about a BILLION years for the earth to cool after forming, for the gases to stablize and produce enough elements to set the stage for carbon based life. In that billion years those elements could develop into simple life and about another half a billion years, a process would evolve to turn the power of the sun into energy on earth - photosynthesis.

Tack on another billion years for life to become complex cells and another billion for those to become multicellular.

Therefore, after about 3 1/2 billion years, we would start to see small animals on a typical planet. At 4 billion years we would see those complex life forms and fishes.... hey we were there already. That took place about 500 million years ago. Which means that, on average, advanced carbon based human life would take about 4.6 billion years to grow and evolve out of the nothingness of a new planet. And how old is earth? 4.6 billion years old.

The sun is only about 30 million years older than the earth, which would tend to indicate that things formed up pretty quickly when the solar system formed around the sun.

One of the problems is that 1 billion years is not enough time for the planet to 'cook up' all the carbon and oxygen needed to produce life. So our theory has it that those primordial elements - nitrogen, helium, hydrogen, oxygen, carbon, came from OUTSIDE the planet and were formed earlier and were partially coalesced when the sun and our planets formed.

These primordial elements came from other suns. To be exact, they came from the death of other suns. When those stars died, they cooked off the carbon and oxygen and those elements were then set free into the ever expanding universe (until it stops expanding anyway).

So the first stars had to be born and die. How long does THAT take? Well, in the case of a star about the size of our sun, that would be about 10 billion years.

So let's add that up. Assuming our sun is an average star, how long would it take, at the earliest, for some stars to be born at the start of the universe (Big Bang?) and then grow and die and then, using earth as a typical example, how quickly could life form?

The life time of a star would be about 10 billion years, from that a star (our sun) would be born, along with its planets. 4.5 billion years later, we would have intelligent life capable of determining the age of the planet, the sun and the universe. All in all about 14 billion years at its quickest.

And how old is our ENTIRE UNIVERSE?????

About 13.7 billion years old.

Well, I'll be damned. If that IS the case and those ARE the averages, the chance of any carbon based civilization being older or more advanced than ours is just about impossible. Chances are, we may be the Best and the Brightest the universe has to look towards. God save us, we aren't up to the task quite yet....

Copyright 2010
Rev Mike MBA BEB