Google DeepMind CEO Demis Hassabis used to get some of his most fulfilling work done between midnight and 3 a.m. A self-described “nocturnal person,” the Londoner devoted the solitude of his overnight shift to catching up on scientific papers, coming up with new ideas, and just plain thinking.Lately, however, even Hassabis’s wee hours are in demand. Much of his team is now based at Google’s home turf in Silicon Valley, where it’s eight hours earlier. As a consequence, video meetings for him ofte...