My position on Extraterrestrial travelers has changed dramatically. Probably more out of frustration than anything else. I do believe that we are being visited by individuals more sophisticated than we can imagine. I like to call what everyone believes to be ETs "ITs" or Intraterrestria travelers.
This theory is based on an amusing mathematical paradox proposed by Enrico Fermi in the 1950s. The Fermi paradox questions the possibilities of finding intelligent extraterrestrial life. More specifically, it deals with the attempts to answer one of the most profound questions of all time: "Are we (the earthlings) the only technologically advanced civilization in the Universe?". The massive radio telescope in Arecibo, Puerto Rico has yet to receive any radio signals that scientists can use to prove that ET is listening despite the millions of home-based PCs processing data on borrowed time.
In fact, from all the signals that our scientists have dutifully shot out into space, none have reached far enough within our galaxy to be answered by civilizations intelligent enough to receive simple radio waves. Our telescopes and imaginations are currently the closest things that we have to time-machines. According to telescopic observations and spectral studies conducted by our Astronomers, a habitable environment has not been found. It seems that Mars is our best shot at getting off this rock--and that's provided we turn Mars into Earth. (terraformed)
The Drake Equation
This equation was devised by Dr. Frank Drake in the 1960s in an attempt to estimate the number of extraterrestrial civilizations in our galaxy with which we might come in contact. The main purpose of the equation is to allow scientists to quantify the uncertainty of the factors which determine the number of extraterrestrial civilizations.
The Drake equation is closely related to the Fermi Paradox
The Drake equation states that
N = R* × fp × ne × fl × fi × fc × L
where:
N is the number of extraterrestrial civilizations in our galaxy with which we might expect to be able to communicate and R* is the rate of star formation in our galaxy
fp is the fraction of those stars which have planets
ne is average number of planets which can potentially support life per star that has planets
fl is the fraction of the above which actually go on to develop life
fi is the fraction of the above which actually go on to develop intelligent life
fc is the fraction of the above which are willing and able to communicate
L is the expected lifetime of such a civilization.
Try the Drake Equation here. If you study the data produced by the equation, you'll see that the chances of life existing elsewhere are slim if not absurdly remote. Most of the variables in the equation are nothing more than optimistic guesswork--but give it a shot, SETI is based on this equation.
Maybe we are alone?
Life as we know it does not exist elsewhere. So, where is life? There isn't sufficient empirical evidence to support the existence of extraterrestrial beings. A common concept used in the scientific method to test the validity of certain ideas is Occam's Razor. To paraphrase, Occam's Razor states that the explanation for a given phenomenon that has the fewest assumptions should be preferred over more complicated ones. The simplest explanation, say pundits to the premise behind the Fermi paradox, is that as a technologically advanced species, weare alone in our part of the Cosmos.
Time and time again...
Stephen Hawking posed the question; "if time travel were possible, why haven't we been visited by tourists from the future?"--maybe we have. We are being visited by strange visitors and have not determined or concluded if they are tourists, invaders or simply musings in the time-space continuum. The apparent physical appearances of these visitors made popular by UFO fanatics, biased investigations and Hollywood begs for an investigation on the future and evolution of Homo Sapien sapien, and possibly our next evolutionary phase.
What will we look like in a million years?
It seems that we are closer to solving the complex mathematical problems that time-travel requires than finding visitors from another planet or mother-ship akin to the Death Star from Star Wars. Our physicists have proven that an atom's orbiting path around a nucleus within a molecule cannot be predicted according to the Heisenberg Principle of Uncertainty. An atom can be tracked within a range of certainty but changes positions immediately when observed directly.
Where does it go? Some physicists believe that it may slip into a different dimension. So, we at least have a theory that transdimensional existence is possible and maybe even probable, but still no ET--silence from the emptiness and chaos of space.
The Grays? Pleadians? why so many different types?
Why so many races?-- different aliens? Are they the results of different evolutionary phases in humanity, mutations, future work on genetic engineering? How is it that "aliens" look distinctly humanoid and appear to be a strange variation of homo sapien man? Their eyes are much larger--bug-like, they seem to be from a place where light is insufficient. Will there be a massive cloud cover over earth now akin to Venus, or apparent to one of the gas giants like Jupiter or Saturn? Will sun light not be available in the far, distant future like it is now.
Species on earth have evolved according to changing earth's climates and environments. What changes will occurr on earth to spawn such beings? Will they live underground in the future? Homo sapiens are only about 20,000 years old and humanoids about 6 million years old. Where in the many millions of years in the future can these visitors come from?
Are they even based on humanoids?
Is our present a threat to their present, our future?
Maybe they have not quite figured out how to travel through probability? Potentials and other uncertainties involved in time travel. Linear travel is all they can do for the instance they exist in. However, these visitors would be a little more cautious if we were somehow threatening their present, our future. If this futuristic culture mastered time-travel then they've seen their own future-- They would also understand how our future, their past, affects them in their present. Have they somehow connected a specific event in our present time to a specific event in their present time, our future? Time travel merely requires an extremely complex group of mathematical equations and mathematical equations can all be solved with more processing power. We will have faster and more powerful computers in the future, we will solve these problems.
Why are they so illusive?
We also know that these visitors are illusive, why? So what if we see them? What harm is there? Why all the secrecy and apparent government cover-ups? Maybe they understand that their involvement in our present, their past can cause some type of time-space continuum rupture thus threatening their existence. Scientists have produced many paradoxical explanations illustrating the cautions of time-travel.
Think about it, if you could jet-ski past Columbus's tired trio of caravels to see what really happened in 1492 as they beached into San Salvador, would you tell them you're from the future and to please not enslave the natives? Would they still attempt to colonize America and make "Americans" or would talking to Chris and his guys cause them to go nuts and abandon the entire mission thinking that an angel intercedes in the natives' behalf--what? Right, try to take that one back to Queen Isabella after she funded his trip when Spain was broke.
Understanding all this, you'd simply jet-ski by the Santa Maria, NiƱa and the Pinta, wave to the ancient sailors with mouths agape and simply inspire nothing more than a mariner's tall-tale and the results of scurvy and lack of hygiene.
You'd be both illusive and quick to get out well before you get blamed for screwing up a universal clock of some sort.
Conclusion.
Bottom line. I don't think that aliens "from outer space" exist, not yet. The likelihood of time travelers from our planet is greater than travelers from the cosmos.
jC - 2004
References
Wikipedia. 2004. Thought Experiment (gedankenexperiment) http://en.wikipedia.org/wiki/Thought_experiment
2think.org. 2004. Occam's Razor http://www.2think.org/occams_razor.shtml