Tuesday, March 19, 2013

Thoughts on Life in the Universe

---Disclaimer: This is a departure from the things I normally post about and is more a train of thought/ philosophical discussion rather than a true position on a topic. ---

There are a number of theories on the nature of the universe, the existence of life outside Earth and the abundance of such life. My own philosophical leaning is that life is an expression of the will of God (or as Carl Sagan said, "We are a way for the cosmos to know itself") and that humans are the ultimate expression of such will (until we find other intelligent aliens out there). Of course this is just my own leanings and much of this post will deal with theory and belief more than rock-solid science.

The generally accepted theory of the creation of the universe involves a big bang and a period of inflation, which is then followed by a period of matter dominating the universe, which is finally followed by a period in which dark energy dominates. We currently live in the dark energy dominated period and it looks as though the known universe will one day die a slow, cold, dark and empty death many trillions of years from now. However, within this model (the inflationary universe theory) there lies an interesting feature. Some areas within the whole universe (we live in the whole universe but can only study the observable universe which may just a tiny part of the whole) may have undergone a period of rapid and eternal inflation which would create "pocket universes." When you look at the math it seems likely that these pocket universes far outnumber the regions where inflation slowed to allow matter to form.

Generally speaking, our little corner of the universe may be the only place life could ever possibly exist. So in a universe which is, to us, infinite, our observable universe (some 93 billion light years in diameter) is all we have to go on. It is possible that other universes exist, but as far as we know there will never, ever, be a way for one life form in our universe to communicate with life in another universe or pocket universe no matter how fast they travel or for how long. For ease of thought, let us assume that our universe is all there is.

If we agree that evolution is the process which gives rise to life (ignoring the possibility of some one or some thing causing evolution to occur), then it would seem logical that life exists throughout the universe. I think I need to list some points to help you see where I'm coming from.

--In the past we thought that it was probable that the only planets that existed were the ones around our sun. Today, we know of hundreds of planets orbiting other stars and there are literally thousands of other potential planetary candidates. Doing some quick math one could arrive at hundreds of billions of planets just within the Milky Way galaxy.

--In the past we thought life only existed on Earth. Today, while there is no evidence of life on other worlds we have found the building blocks of life, amino acids, in asteroids, interstellar gas clouds, and practically everywhere you could look.

--On Earth there are many millions of species. Life takes the form of plants, fish, land animals, birds, bacteria, fungi, and a myriad of other forms.

Now, depending on the assumptions used, with Drake's Equation:

You can come to one of three general conclusions; 1) we are completely alone in the universe, 2) life exists but is far and few between, or 3) life is practically everywhere.

The Fermi Paradox plays into my thoughts for today and I consider it a stronger idea now than when it was first discussed in the 1950's. Given that we know of a vast number of planets, that many of them lie within habitable zones, that the building blocks of life are found in every corner of the universe in some form and given that life on Earth exists in so many forms - including within rock itself and free from the need of sunlight, why haven't we found any?

One might expect that some type of life (or evidence of a metabolic process) evolved on Mars or perhaps in the deep oceans of distant Jovian moons. The simple fact is, we have no evidence. There is no doubt that Mars once had a magnetic field, liquid oceans and a thicker atmosphere. There is little doubt that life on Earth began within a few hundred millions years of the planet's formation, so, would it not stand to reason that life should have evolved on Mars as well? There are many features (like stromatolite formations and oil) which are made up of the compressed bodies of trillions of tiny critters and plants. Shouldn't a similar thing have occurred elsewhere?

We have found life on Earth almost everywhere we have looked. Life above, on, and within the Earth's crust and seas; even miles above Mt. Everest and thousands of feet within solid rock. Every time (to my knowledge) that we thought Earth was unique or special in some way we have found out that we are as common as sand on a beach, albeit pretty sand. The only area without even circumstantial evidence is in the arena of life.

Everything I have discussed brings me to this question, what if life really is unique to Earth? Would it be a stretch to assume we alone (life on Earth) might actually have been created for a purpose (again, ignoring any single faith and even the concept of a god as commonly understood, but simply, the ultimate expression of will) or are we indeed the result of the most random of random fluctuations? Either way, it gives me pause.

If we exist simply because we are here and, as Stephen Hawking has said, the only purpose or meaning in life is what we give it, then shouldn't we take the opportunity to achieve all we can achieve in our short life spans? If there is no heaven or hell then the only things we will ever learn or experience will happen while we're alive. I think that regardless of how we came to be (via chance or God) we owe it to ourselves to stop acting so incredibly childish and really seize the moment. Mankind figured out the Earth orbited the Sun 2,300 years ago (although it was forgotten) and we have truly wasted hundreds of millions of lives in conflict. Can you imagine where we would be if we had not been afraid of logic and reason, if we had not been so bent on destruction? Do you really think our purpose (either from God or the purpose we give ourselves) should be to waste the only existence we will ever have? To waste the only intelligent life that possibly has ever, will ever, arise in the universe?

--Jacob Bogle, 3/19/2013

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