Searching For A Standard Drake Equation


In 1961 Frank Drake proposed the following equation, to try to estimate the number of civilizations, N, capable of making radio communications in our galaxy where: N = number of civilizations in the galaxy that emit radio signals; R* = rate of star formation; fp = fraction of them with planetary systems; ne = number of habitable planets in each planetary system; fl = fraction of them that have developed life; fi = fraction of them that have developed intelligent life; fc = fraction of civilizations that perform interstellar communications; and L = length of time that these civilizations release detectable signals into space.

In the 20th century the scientific search for extraterrestrial intelligence began, and the Drake equation was proposed to estimate the number of extraterrestrial species humanity could attempt to detect, N.

This paper discusses the need to update and standardize this equation. A new and more accurate expression is deduced which contains the classic equation as a particular case, and its advantages are discussed. A necessary condition is also stated for its use in scientific contexts: if N is defined as the total number of civilizations like ours then N = 1, given that we exist, and consequently the working hypothesis of the SETI project can be expressed as N>1. In this case, the Drake equation is being applied in a scientific way, because it is trying to test a hypothesis based on evidence.

Jose Antonio Molina Molina
(Submitted on 2 Dec 2019)

Comments: 15 pages, 3 tables
Subjects: Popular Physics (physics.pop-ph); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1912.01783 [physics.pop-ph] (or arXiv:1912.01783v1 [physics.pop-ph] for this version)

Submission history
From: José Antonio Molina
[v1] Mon, 2 Dec 2019 19:15:47 UTC (476 KB)
https://arxiv.org/abs/1912.01783
Astrobiology, SETI

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