science

One paradox, one number: the century-long argument that proved information is physical. Part one of two.

Entropy is a count, not a mess. Get that right and the arrow of time, life and information all fall into place.

The Third Law: Absolute Zero and the Unreachable Floor In the early 1900s, Walther Nernst was studying chemical reactions at low temperatures. He noticed something strange: as temperature dropped, the entropy change in reactions approached zero. No matter what chemicals he used, the same pattern emerged. Nernst proposed a new

The Second Law: Why Time Has a Direction Here's a video: an egg falls off a counter, hits the floor, and splatters. Now play it backward: fragments leap up, yolk reconstitutes, shell reassembles, the intact egg rises to the counter. The backward video violates no laws of mechanics.

The First Law: Energy Cannot Be Created or Destroyed In the early 1840s, a young German physician named Julius Robert Mayer was working as a ship's doctor in the tropics. He noticed something odd: when he bled patients in Java, their venous blood was unusually red—almost as

The Zeroth Law: Why Temperature Makes Sense Here's a question that seems stupid until you think about it: How do you know a thermometer is telling the truth? You stick a thermometer in boiling water, it reads 100°C. You trust it. But why? The thermometer isn'