Eifelheim - Michael Flynn [11]
“Christaller’s original survey,” said Tom, who had not noticed her sortie. “Land Württemberg, nineteenth century.”
Sharon spared the screen a cursory glance. “All right—” Then, almost against her will, she leaned toward the computer. “Another honeycomb,” she said. “Is that a common pattern?”
He didn’t answer. Instead he showed her a series of maps. Johnson’s study of Late Uruk settlements around Warka. Alden’s reconstruction of Toltec polities in the Valley of Mexico. Skinner’s analysis of Szechuan villages. Smith’s anomalous study of western Guatemala that found two grids, Indio and Ladino, superimposed on each other like parallel universes.
“Now check out this map. Verified sites of ancient Sumerian and Elamite pueblos.”
To her own annoyance, she found herself intrigued. One such map might be an oddity; two or three, a coincidence; but not this many. “Why is that dot red?” she asked.
Tom regarded the screen with indulgence. “My claim to fame. There was no known pueblo at that site. But ancient writings are full of references to places we’ve never pinned down. So, I sent old Hotchkiss an e-mail, telling him to move his dig. That made him mad—he’s an old-school microhistorian. But what really ticked him off was when he finally found the ruins, two years later, right where I’d told him they would be.”
So his patterns had predictive value, too. Patterns were interesting. They could lead, like astrology, to real science. “There has to be a cause,” she said.
He gave her a satisfied nod. “Ochen khoroshó.”
“Okay, I’ll bite. What is it?”
He tapped a fingernail against the display. “Each locus provides some degree of biopsychological reinforcement to its inhabitants. Rich bottomlands, a vein of silver, a plentiful supply of guano, anything. Andere Länder, andere Sitten. The intensity of that reinforcement defines a potential function over the landscape, and the gradient of that potential is a force we call affinity.”
Sharon withheld comment. She had never considered Tom’s “forces of history” as anything more than a metaphor. She was a physicist, and physicists dealt in real forces.
“If affinity were the only force,” Tom continued, “the entire population would be sucked into the local maximum. But population density itself creates a second potential because, cæteris paribus, people prefer wide open spaces to getting someone’s elbow in their ear. So there’s a countertendency for the population to spread out evenly across the landscape in a kind of cultural heat death. The interaction between these two forces generates the differential equations for a reaction-diffusion process. Population accumulates at the equilibrium sites, with settlement sizes distributed according to Zipf’s rank-size law. Each settlement generates a cultural potential field whose strength is proportional to its wealth and population and which diminishes with the square of the distance. Geographically, these settlements and their hinterlands form hexagonal patterns called Christaller grids. Ert, Nagy kisasszony?”
“Ertek jol, Schwoerin ur,” she answered. Sharon wasn’t entirely convinced, but if she argued the point, they’d be up all night, settle nothing, and she’d never get back to Janatpour space. Besides, the model did account for that remarkable consistency of settlement patterns. She pursed her lips. If she wasn’t careful, she’d get sucked into solving his problem instead of her own. “So, where does this Eifelheim of yours fit in?”
Tom flipped his hands up. “It doesn’t.” He called another map onto the screen. “Here’s the Black Forest. Notice anything odd?”
After all those maps, the empty cell fairly jumped out at her. Sharon touched the screen, her finger dancing from village to village. Bärental, Oberreid, Hinterzarten, St. Wilhelm … The roads all twisted around the blank spot, some doubling back on themselves to avoid it. She frowned. Tom was right. There should be a village there.
“That,” he announced sourly, “is Eifelheim.”
“The little town that wasn’t there,” she murmured. “But how can a town that isn’t there have a name?”