THE INFERNAL By Mark Doten Graywolf. 422 pp. Paperback, $18In a torture chamber in the Middle East, the man asking the questions waxes poetic. “Imagine,” he dreams, a “fully expressive body, not this burnt and ruined thing.” The yearning seems a hideous irony — a torturer’s job, after all, is both to ruin a body and render it “expressive” — but in Mark Doten’s prodigious, provocative debut, “The Infernal,” it’s more.