The formula is no longer:
Key Half-Life 1.1 introduces a crucial refinement: The half-life is not just a function of time, but of access, re-use, and entropy decay. Every time the key unlocks a door—every session, every API call, every wrapped secret—the half-life shortens. Not linearly. Not predictably. But inexorably. key half life 1.1
[ P(t) = 2^{-t/T} ]
[ P(t, u) = 2^{-t/T} \cdot (1 - e^{-\lambda u}) ] The formula is no longer: Key Half-Life 1
Consider a master key used to derive subkeys for microservices. In version 1.0, you might rotate that master key every 90 days. In 1.1, you realize: after 1000 derivations, the key’s effective strength has halved. Not because the math broke, but because side channels, memory scraping, and log leaks chip away at the secret bit by bit. Not predictably
This is the quiet revolution of 1.1: moving from static security to kinetic security . The half-life is not a warning. It is a design parameter.