The universe waited 14 billion years for this

Consider the humble barcode scanner.

That fleeting red line, painting groceries or library books, feels utterly mundane. We barely register it. Yet, trace its lineage, and you plummet down a rabbit hole into the strangest, most powerful physics ever conceived, culminating in a moment, barely sixty-five years ago, when humanity fundamentally altered the nature of light itself.

The universe, as far as we can tell, shone with fundamentally different light for the rest of the 14 billion years since the beginning of time.

A detailed simulation of a light source with “random” light. (This is an animation! Notice not much happens.)

Light was, for all intents and purposes, wild. Sunlight splashed, firelight flickered, starlight glimmered — all beautiful, all essential, but all inherently messy. This is incoherent light.

It illuminates, it warms, it exposes photographic plates, but it’s fundamentally unruly. Even nature’s own light-making marvels, like the ghostly glow of bioluminescent fungi or the intricate signals of fireflies, produced this same beautiful, random visual noise. It seemed an immutable property of the visible world. Why wouldn’t it be?