 | = | number of civilizations with which humans could communicate |
 | = | mean rate of star formation |
 | = | fraction of stars that have planets |
 | = | mean number of planets that could support life per star with planets |
 | = | fraction of life-supporting planets that develop life |
 | = | fraction of planets with life where life develops intelligence |
 | = | fraction of intelligent civilizations that develop communication |
 | = | mean length of time that civilizations can communicate |
Recently scientists have re-examined the Drake equation - above - that as a thought experiment attempts to quantify the number of communicating extraterrestrial intelligences (CETIs) in our galaxy - applying new found knowledge of the probable numbers of exoplanets, the number of those planets that lie in the habitable zone, and the likelihood of intelligent life evolving on them. 36-46,000 CETIs are estimated to have evolved sometime in the history of our galaxy by these new calculations. But given our galaxy's immense size and numbers of stars - some 200 billion - and their planets, these few CETIs means we could search for them for hundreds of thousands of years and never make contact.
But the Drake equation and now these refinements to it possess a major flaw. The assumption that L, the mean length of time a civilization communicates before destroying itself or being destroyed, is tied to one planet or even one solar system is false. Doomsayers think it impossible or at least extremely rare that civilizations survive their technological explosions because they cannot imagine CETI's spreading out to multiple worlds to include artificial ones before destroying themselves. Everything rides on the health of their home planets and on an entire world getting along once the ability to destroy themselves is developed. Futhermore they assume CETIs are biological.
But we are about to about begin the permanent colonization of Mars in just the next thirty years. Our chances of surviving as a communicating species goes up dramatically the moment we do so. First rockets to enter space to the colonization of another world in just 100 years time. A time so brief on a galactic scale as to be instantaneous. A time so brief it simply must have occurred before in in our galaxy,
Furthermore we will most likely develop super artificial general intelligence (AGI) in the next fifty years. A sentinent intelligence smarter than us capable of expansion into space on its own, resistant to radiation, vacuum, and microgravity. Fron first electronic computers to super AGI in 130 years - a blink of the eye on galactic scales.
I call it bioplanetfilia - the prejudice that CETI's continued existence is dependent on the planet and/or sun of their origins, and that CETIs are biologic. All discussion seems to stop with these limiting condition, the all eggs in one basket once CETI's evolve, and the slim chances of surviving their technological explosions because of it.
But if just one CETI - biologic or 'artificial' - beginning say a billion years ago - survived long enough to begin to populate space - their chances of survival as a communicating species would improve dramatically. In fact it becomes so good that the chances approach unity. And it is likely that by now they are ubiquitous in our galaxy - be it on planets, artificial worlds, or imbued within the fabric of space-time itself. Not only would they be ubiquitous but after so much time it is likely a multitude of factions that chose different evolutionary pathways have evolved into a dizzying array of species -biologic and nonbiologic - devoid of knowledge of a common ancestor.
So then, where are they? Why haven't we heard from them?
It is possible they evolved to a point where they left this universe perhaps to escape the inability to make contact with others given this universe's shear size and the absolute limiting velocity of light. Leaving could mean creating and then existing in simulated universes of their design. Or perhaps leaving to different physical universes, or existing in a way in this one we cannot comprehend. Afterall intelligence probably has no upward limits and would be expected to grow with technological ability.An intelligence a million fold ours may not be recognizable.
But if at least some of them chose to remain in a way we can comprehend, the answer to making contact with them will most likely not rely on them, but on us, our technological advancement, and how we choose to observe for them. Modulated electromagnetic radiation will not be the mode of communication used by intragalactic intelligence. It is too slow requiring tens of thousands of years on average for an answer to hello. Nor will planetary atmospheric pollution be the means to detect them on exoplanets. Pollution is waste - waste and pollution must be solved very early on during CETI's technological explosions or they cease to exist. So how then? Good question.
One thing is sure. Colonizing space is the key to our species and our civilization's survival. It will be up to us to do so post haste in order to survive long enough, and to become smart enough, to find our CETI's.
