I remember it vividly. Across a table, five profs. I’m frightened, trying to look casual as sweat drips down my face. But I’m keeping afloat; I’ve managed to babble superficially, giving the illusion that I know something. Just a few more questions, I think, and they’ll set me free. Then the examiner over at the end of the table – the guy with the twisted little smile – starts sharpening his pencil with a penknife.
“I’ve got just one question, Cliff,” he says, carving his way through the Eberhard-Faber. “Why is the sky blue?”
My mind is absolutely, profoundly blank. I have no idea. I look out the window at the sky with the primitive, uncomprehending wonder of a Neanderthal contemplating fire. I force myself to say something—anything. “Scattered light,” I reply. “Uh, yeah, scattered sunlight.”
Well, words came from somewhere, out of some deep instinct of self-preservation. I babbled about the spectrum of sunlight, the upper atmosphere, and how light interacts with molecules of air.
I’m describing how air molecules have dipole moments, the wave-particle duality of light, scribbling equations on the blackboard, and . . .
An hour later, I’m sweating hard. His simple question—a five-year-old’s question—has drawn together oscillator theory, electricity and magnetism, thermodynamics, even quantum mechanics. Even in my miserable writhing, I admired the guy…
By Clifford Stoll, from “The Cuckoo’s Egg”
