Some 15 years ago, as a young researcher trying to push a new idea, I was accused publicly by a much more eminent fellow physicist of not understanding entropy. Ever since then, I’ve been fixated with trying to really understand entropy. Personal pride, and the emerging scholarly consensus, require me to point out that I have since been proved right in what I was trying to say back then, but the intervening 15 years have taught me that neither I nor my eminent colleague had a full grasp of the mysteries of entropy, still less its mystical (what I might now refer to as ‘theological’) overtones.
Entropy is what makes life worth living. Arguably the most important of all the laws of physics (at least where biological life is concerned), the Second Law of Thermodynamics declares that the entropy (disorder) of a closed system (one that is thermally insulated from its surroundings) can never decrease, but must always increase (or at the very least stay the same). This turns out to provide a reasonably straightforward way into an otherwise notoriously-difficult problem – how to define life. Continue reading