A Stationary Drake Equation Distribution as a Balance of Birth-Death Processes

Abstract: Previous critiques of the Drake Equation have highlighted its deterministic nature, implying that the number of civilizations is the same at all times. Here, I build upon earlier work and present a stochastic formulation. The birth of civilizations within the galaxy is modeled as following a uniform rate (Poisson) stochastic process, with a mean rate of $\lambda_C$. Each then experiences a constant hazard rate of collapse, which defines an exponential distribution with rate parameter $\lambda_L$. Thus, the galaxy is viewed as a frothing landscape of civilization birth and collapse. Under these assumptions, I show that N in the Drake Equation must follow another Poisson distribution, with a mean rate $(\lambda_C/\lambda_L)$. This is then used to rigorously demonstrate why the Copernican Principle does not allow one to infer N, as well evaluating the algebraic probability of being alone in the galaxy.