Drake Equation? Fermi Paradox?
If life is common, then where is everyone? A
new paper claims to have the answer, but their conclusions are highly suspect.
Water, light, heat, organic molecules, and the ingredients for life are indeed everywhere. But aliens of any type have yet to show themselves. For all we have hard evidence for, Earth may be it for life in the entire Universe.
If that sounds pessimistic to you, or, as Carl Sagan put it, "an awful waste of space," you're not alone. [Nature doesn't waste energy]
Although we knew very little about the various parameters in it, the Drake Equation is still used by many today to estimate the number of potential civilizations we can communicate with in space.
https://thumbor.forbes.com/thumbor/9...-Rochester.jpg
Despite the replacement of point estimates with probabilistic distributions, as the authors impose, there is still no evidence that we can say anything sensible about these likelihoods. In the absence of evidence, theorists aren't theorizing based on sound science; they're simply making numbers up. The authors state their methodology as such:
Unfortunately, this falls prey to what I call the first law of computer science: garbage in, garbage out. Historical estimates and the authors' judgments are no substitute for the data we need, and do not have.
Source
conclusion in this case seems to be 'Jury's still out'