Yushun Zeng squishes cancer cells in a petri dish at work. No, not with his ungainly, macroscopic human fingers. Zeng, an engineering graduate student at the University of Southern California, has ...

Heat is not supposed to behave like this. In everyday life, warmth seeps and diffuses, spreading from hot to cold in a slow, smearing process that never looks anything like a crisp sound wave. Yet ...