As the United States experiences a brain drain, Europe is emerging as a key research partner for China as both benefit from an influx of young scientists from America. Rapid changes in geopolitics have brought “massive changes in the global flow of talent”, according to Patrick Cramer, the president of Germany’s Max Planck Society, a leading research body in Europe. “These are exactly the questions that I think about all day,” Cramer said during an interview in Shenzhen in April. “One trigger is...