Quote:
Originally Posted by Steven Lyle Jordan
From the Wiki:
The factor L is the only one that represents a factor of time, and as I indicated, specifies how long a civilization can send signals... but not when. A new variable, S, needs to be introduced that compares the period of time during which a civilization exists simultaneously with our own, in order for such signals to have a chance of being intercepted.
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Which is in direct contradiction to what I just posted. I think you are interpreting something different than others. The quote I posted specifically says "SIMULTANEOUSLY" and that is accounted for.
Again:
Quote:
Rationale and Justification for the Search
Estimates of the number of extraterrestrial civilizations
in our galaxy rest upon an elegant but simple
heuristic known as the Drake Equation. This states
that the number of extraterrestrial civilizations existing
simultaneously with our own depends upon a
combination of physical, biological, and social variables
(Drake and Sobel, 1992). These are the number
of suitable stars in our galaxy, the fraction of those
stars that have planets, the fraction of those planets
that give rise to life, the fraction of life forms that
evolve into technologically advanced civilizations,
and finally the average longevity of advanced civilizations.
(Longevity is important because it affects the
chances that civilizations will exist simultaneously.)
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