cosmic ray

Tag archives for cosmic ray

“On what can we now place our hopes of solving the many riddles which still exist as to the origin and composition of cosmic rays?” -Victor Francis Hess We’ve come a tremendously long way in our understanding of the Universe, but there are plenty of mysteries still to be revealed. Way back in the late…

Why doesn’t Light Age?

There’s a graduate student that I’m sort-of mentoring/working with at Arizona, named Xiaoying Xu (hi Xiao!). She’s bright and curious, and she asks some very good questions. She asked me one yesterday that’s pretty tough to wrap your head around: How do I explain to someone why light doesn’t age? Well, here on Earth, time…