Chilean author Benjamin Labatut has created a tour de force fiction-nonfiction hybrid, “When We Cease to Understand the World,” that in a slim volume barely longer than a novella pulses through key early 20th Century physics, mathematics, and mass evil, focusing on key luminaries. Fritz Haber invents poison gas, Schrodinger and Heisenberg engage in a titanic battle over the invention of quantum physics, Karl Schwarzschild invents the black hole … all these tales told as pithy education but also imagining personal battles commensurate with the scientific ones. A final chapter sees the narrator engage with a “night gardener” about the merits of all this thinking. To an ex-mathematician like me, the most spellbinding chapter concerns Alexander Grothendieck, a mathematical prodigy of such obsession that he mesmerized a generation, and his baffling disciple Shinichi Mochizuki who in 2012 published six hundred pages of proof of a key conjecture, but published it on his own blog, and no one, but no one, could understand it! Labatut writes with a lyrical fervor that hypnotizes, even if sometimes you wonder where he is going. “The quantity of fiction grows throughout the book,” confides the author, and the mixing of “real” and “imagined” could irk some readers. I rode with the flow and experienced a sustained rush of intellectual and emotional pleasure. When We Cease to Understand the World is a maverick, kinetic boon.