Consider the crush of bodies at the doors, six hundred humans pressing toward a discounted television, and what it actually is at the level that matters: a fluid. A dense, warm fluid of primates, each one about sixty percent water by mass, jostling under thermal agitation exactly the way gas molecules do in a heated chamber.
Raise the pressure at the entrance, narrow the aperture, and the flow goes turbulent. We have equations for this. The crowd obeys them without reading them.
Watch one person seize the television. The muscles in the arm hydrolyze a molecule called ATP, and the energy released to lift a thirty-pound box came, originally, from sunlight: photons that crossed ninety-three million miles, struck a leaf, and were folded into sugar years before this store existed. That arm is running on captured starlight, spending it on a markdown.
And the television itself. Its screen is a lattice of silicon, refined from ordinary sand, coaxed into switching electrons at intervals of a few billionths of a second, faster than any nervous system in that entire shouting crowd can perceive. Nobody in the checkout line could feel a nanosecond if it landed on them. They are buying a device that lives, natively, in a fraction of time their own bodies cannot register.
Here is the part that stops me cold. Every silicon atom in that screen, every calcium atom in every straining bone at those doors, was forged inside a dying star and flung across the galaxy in an explosion before the Earth had formed. So this is what the debris of ancient supernovae does, once it cools and organizes and wakes up: it sets an alarm for four in the morning, and it stampedes.