Hi, I'm doing a presentation about the fermi paradox and I use the drake equation:(adsbygoogle = window.adsbygoogle || []).push({});

[itex] N = R_* \times f_p \times n_e \times f_I \times f_i \times f_c \times L [/itex]

Where the symbols have their usual meanings. I don't understand why this would give the number of civilisations whose EM emissions are detectable. Surely it would give the number of civilisations created in L years whose EM emissions are detectable? If somebody could explain why the L (length of time which such civilisations release detectable signals into space) would give the N value that would be much appreciated, thanks.

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# The Drake Equation

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