Barney relaxed a trifle. “You may,” he said. “Especially since we’ve got to explain it to some of the others.”
He stubbed out his cigar and began on a fresh one. “Let me put the proposition in nickel words first,” he said, “then the experts can correct and amplify according to their specialties. Our universe has a straightforward space‑time geometry, except in odd places like the cores of white dwarf stars. Demons can move around in it without trouble?in fact, they can play tricks with distance and chronology that gave them the reputation of being supernatural in olden days?because their home universe is wildly complicated and variable. Modern researchers have discovered how to get there, but not how to travel around or remain whole of body and mind.
“Well, Steve’s information that we could reach any point in hell time, if we knew the method opened a door or broke a logjam or something. Suddenly there was a definite basic fact to go on, a relationship between the Low Continuum and ours that could be mathematically described. Dr. Falkenberg set up the equations and started solving them for different conditions. Dr. Griswold helped by suggesting ways in which the results would affect the laws of physics; Bill Hardy did likewise for chemistry and atomistics; et cetera. Oh, they’ve barely begun, and their conclusions haven’t been subjected to experimental test. But at least they’ve enabled Dr. Nobu, as a metaphysicist, and me, as a practical engineer, to design some spells. We completed them this morning. They should protect the expedition, give it some guardianship when it arrives, and haul it back fast. That’s more than anybody previous had going for them.”
“Insufficient.” Charles was the new objector. “You can’t have a full description of the hell universe?why we don’t have that even for this cosmos?and you absolutely can’t predict what crazy ways the metric ‘there varies from point to point.”
“True,” Barney said.
“So protection which is adequate at one place will be useless elsewhere.”
“Not if the space‑time configuration can be described mathematically as one travels. Then the spells can be adjusted accordingly.”
“What? But that’s an impossible job. No mortal man?”
“Right,” Ginny said.
We gaped at her.
“A passing thing Steve heard, down in the crypts, was the clue,” Ginny said. “Same as your remark, actually, Admiral. No mortal man could do it. But the greatest geometers are dead.”
A gasp went around the table.