Important contributions to physics don't always come from career physicists. The fields of theoretical physics and mathematics overlap, well, a lot. Theoretical physics is mainly math, and there are times when mathematicians contribute landmark theorems to physics. One such person, whom no-one ever seems to learn about in high school or even introductory college physics (I certainly had no idea this person existed until late in my physics education) was Emmy Noether. Described by such heavyweights like Albert Einstein, Norbert Wiener, and Hermann Weyl as "the most important woman in the history of mathematics," it's a bit surprising that more people don't know her name, or what she did. It may be due to the fact that her eponymous theorem in physics requires rather advanced physics and mathematics, but I'm going to endeavor to explain it anyway.
Time is a funny thing. It's passage may seem constant, but it totally isn't. And I'm not just talking about how boring or tedious days drag by. See, this pretty obscure physicist by the name of Albert Einstein managed to codify a new area of physics back in the early 1900's which we call Special Relativity. He was the main reason the idea of the luminiferous aether (which I talked about in my post on Light) was discarded, because it showed the speed of light to be an absolute, universal constant, regardless of reference frame. Which is cool and all, but what does light have to do with time?