text:  You know when a child constantly asks the question, why, after every answer? Maddening, right? Particle physicist Harry Cliff admits he was probably that kind of kid. You kind of end up either a physicist or a cosmologist. And so that's the kind of mentality, I think. It's that kind of curiosity about the world. And I think I was one of those kids who was probably exhausted my parents by continually asking questions.