A triumph of classical filmmaking for a modern audience, “Adventures of a Mathematician” revisits the Manhattan Project through scientific, ethical and Jewish lenses. Forgotten your calculus? Simple geometry is more than sufficient to follow the triangular saga of Polish Jewish brainiac Stanislaw Ulam: from the cloistered classrooms of Harvard to Robert Oppenheimer’s atomic-bomb “startup” in dusty New Mexico back to Lvov, Poland (where his parents, sister and niece live in tenuous safety until the Nazis blast across the border). The 102-minute biographical drama is available for streaming Feb. 26-28 in the S.F.-based Jewish Film Institute’s annual WinterFest, which is virtual this year.