The formula is based upon guesses of each parameter with such wide possible values that it can mean anything at all. That’s isn’t science, its faith in mathematical form, because no estimate can be shown to be wrong and therefore unfalsifiable.

Popper describes how science should and sometimes does work.

Kuhn describes how science works in reality more often than not.

It’s idealist versus cynic, as I see it.

Oh, and by the way, Pat Michael’s and Robert Balling’s book Climate of Extremes goes on at length about how Kuhnian “normal science” applies very well to this issue. Worth checking out, I think!

Perhaps f_c isn’t completly un-estimatable. Wireless comunication seems to be a natural evolutionary of technology. Surely at some point in technological evolution people will develop television. Of course, I’m not sure it will ever be possible to detect such signals at any sufficient distance. Also as technology becomes more advanced people are able to transmit more information with less power so perhaps the dectection problem is extreemly difficult.

I wonder what it would take for a signal to be detectable and how an alien race would know how to look for it or even what it means. Consider some of the problems of detection. I presume all frequencies won’t travel at the same speed so I image the original waveform would be quite difficult to reconstruct even if it is highly noise resistant. (How will the detector know how much phase delay there is for each frequency component or how long the word length is)

As for f_i, who knows……..maybe a new field in mathematics will develop called evolutionary statistics. How many possible gene combinations are there (given a finite genome length)? How likely is each combination to survive? Or perhaps put another way, what is the average time to extinction for a given species? How long on average would it take to develop advanced technology (social evolutionary statistics). Who knows what kinds of advance problems we might solve in the future. You may think the question is uninteresting. I think it is interesting. Besides isn’t what is interesting somewhat subjective?

“From: A Dictionary of Psychology | Date: 2001 | Author: ANDREW M. COLMAN | © A Dictionary of Psychology 2001, originally published by Oxford University Press 2001. (Hide copyright information) Copyright information
2-4-6 problem n. A problem of concept formation in which people are given the ordered triple of numbers (2, 4, 6) and are invited to try to generate further examples of triples conforming to an unspecified rule that the example obeys, trying to home in on the correct rule on the basis of simple right/wrong feedback after every guess. The actual rule is any ascending sequence, but the example invites people to form more specific hypotheses, such as ascending even numbers or numbers ascending by equal intervals. It was introduced in 1960 by the English psychologist Peter C(athcart) Wason (1924–2003), who found that people tend to try examples consistent with such more specific hypotheses, such as (10, 20, 30) and seldom try examples that would refute them such as (10, 11, 30), thus manifesting confirmation bias and failing to find the right answer but often becoming increasingly convinced of the rightness of their incorrect hypotheses. Also called Wason’s 2-4-6 problem. See also problem solving.From: A Dictionary of Psychology | Date: 2001 | Author: ANDREW M. COLMAN | © A Dictionary of Psychology 2001, originally published by Oxford University Press 2001. (Hide copyright information) Copyright information
2-4-6 problem n. A problem of concept formation in which people are given the ordered triple of numbers (2, 4, 6) and are invited to try to generate further examples of triples conforming to an unspecified rule that the example obeys, trying to home in on the correct rule on the basis of simple right/wrong feedback after every guess. The actual rule is any ascending sequence, but the example invites people to form more specific hypotheses, such as ascending even numbers or numbers ascending by equal intervals. It was introduced in 1960 by the English psychologist Peter C(athcart) Wason (1924–2003), who found that people tend to try examples consistent with such more specific hypotheses, such as (10, 20, 30) and seldom try examples that would refute them such as (10, 11, 30), thus manifesting confirmation bias and failing to find the right answer but often becoming increasingly convinced of the rightness of their incorrect hypotheses. Also called Wason’s 2-4-6 problem. See also problem solving.”
http://www.encyclopedia.com/doc/1O87-246problem.html

I learned about this reading a thread on physicsforums called, “Is the peer review process biased”
http://www.physicsforums.com/showthread.php?t=293043&page=2