MortalityFunctions

 

Death, an old metaphor says, is an archer who shoots at you every year — and whose aim starts out poor but becomes increasingly accurate as you get older. That image turns out to be good math. Take a life expectancy table and fit a curve to the chance of dying for each age group. You'll find (after an initial blip of infant mortality) that the probability density of bucket-kicking grows with time in the exponent, starting from a tiny number but doubling and redoubling at a steady pace. Solve the differential equation: the number of survivors shrinks like exp(-exp(t)), hyperexponentially.

Grim odds — and there are reasons to believe the model is plausible. Many diseases involve cumulative damage, a sequence of low-probability events. The body has systems designed to spot and fix snafus before they get serious. Over time, however, repair mechanisms themselves break down, and the integrated effect is an ever-more-rapidly increasing rate of problems. Things fall apart ....

Monday, October 30, 2000 at 05:45:54 (EST) = 2000-10-30

TopicScience - TopicLife


(correlates: ToggleMe, BiosFear, MovementForeAndAft, ...)