Her smiling face in the weak light made him think of something he’d never seen before, the sun cast onto a screen. Once the violent flares disappeared, the magnificence that remained couldn’t help but make his heart skip a beat. He smiled, too, hoping she could see his smile.

“Oh, we can look at the brain all we want,” he said, “but consider this: Say a mushroom-shaped thing you can hold in one hand turns out to be a rich and varied universe. From a certain philosophical viewpoint, this universe is even grander than the one you observe. Even though your universe is tens of billions of light-years wide, it’s been established that it’s finite. My universe is infinite because thought is infinite.”

“Ah, not everybody’s thoughts are infinite but, Doctor, yours seem to be. As for astronomy, it’s not as rarefied as you think. Several thousand years ago on the banks of the Nile and several hundred years ago on a long sea voyage, it was a practical skill. An astronomer of the time often spent years marking the positions of thousands of stars on star charts. A census of the stars consumed their lives. Nowadays, the actual work of astronomical research is dull and meaningless. For example, I study the twinkling of stars. I make endless observations, take notes, then make more observations and take more notes. It’s definitely not sublime as well as not rarefied.”

His eyebrows rose in surprise. “The twinkling of stars? Like the kind we can see?” When he saw her laugh, he laughed, too, shaking his head. “Oh, I know, of course, that’s atmospheric refraction.”

“However, as a visual metaphor, it’s pretty accurate. Get rid of the constant terms, just show the fluctuations in their energy output, and stars really do look like they’re twinkling.”

“Is it because of sunspots?”

She stopped smiling. “No, this is the fluctuation of a star’s total energy. It’s like how when a lamp flickers, it’s not because of the moths surrounding it, but because of fluctuations in voltage. Of course, the fluctuations of a twinkling star are minuscule, detectable only by the most precise measurements. Otherwise, we’d have been burned by the twinkling of the sun long ago. Researching this sort of twinkling is one way of understanding the deep structure of stars.”

“What have you discovered so far?”

“It’ll be a while before we discover anything. For now, we’ve only observed the twinkling of the star that’s the easiest to observe—the sun. We can do this for years while we gradually expand out to the rest of the stars…. You know, we could spend ten, twenty years taking measurements of the universe before we make any discoveries and come to some conclusion. This is my dissertation topic, but I think I’ll be working on this for a long while, perhaps my whole life.”