Back in December I posted a picture of the poster that I was taking to the Dallas Astrophysics Symposium. Lots of people asked what it all meant and I promised I’d answer eventually. Well, I've finally found the time to at start expanding on the poster in small chunks. The following is a first attempt and will make far more sense to physicists than it will to anyone else, (at least I hope it’ll make sense to someone).. I’m using these posts as a practice ground for explaining these concepts simply and the explanations should get better as time progresses. In the meantime, thanks for being my practice audience if you decide to read this! If you have questions, please ask them, and if you can see an obviously better way of expressing the ideas, and you’d like to share it that would be awesome and help a lot! Physicists in the early 1900s defined a quantity called rapidity that serves as a way of measuring how fast a particle is traveling in spec...