Did the ever dead outnumber the living and when? A birth-and-death   approach
  This paper is an attempt to formalize analytically the question raised in "World Population Explained: Do Dead People Outnumber Living, Or Vice Versa?" Huffington Post, \cite{HJ}. We start developing simple deterministic Malthusian growth models of the problem (with birth and death rates either constant or time-dependent) before running into both linear birth and death Markov chain models and age-structured models. 
Jean Avan (LPTM), Nicolas Grosjean (LPTM), Thierry Huillet (LPTM)
math.PR cond-mat.stat-mech q-bio.PE