Misconceptions in Relativity

Over at THE END OF EVOLUTION thread, Lucy the Ape claimed that I had stated that "mass increases with velocity", and that I was wrong. Well, if I had ever made such a vague statement, I would probably have to agree that it is wrong. But equally wrong would be the statement "mass does not increase with velocity". Both are "wrong" in their vagueness, and both can be correct given the right context.This thread is to explore and banish the myriad of misconceptions that arise in Relativity (and related physics areas). We can look at the "paradoxes" of Special Relativity, revisit Percy's favourite topic of cosmological vs doppler red-shift, and delve into black holes, wormholes and time-travel... QM could do with a thread of its own, but there could well be some overlap.The idea is for brief responses that may lead, if interest dictates, to new threads on specific topics. I would prefer not to get bogged down in any one area in this thread. My time can be limited, so hopefully Son Goku can jump in and help, plus anyone else who thinks they can clarify a situation. But as it is a thread on banishing misconceptions, I will not be pulling any punches if replies start to exacerbate those misconceptions Lucy the Ape has introduced our first misconception, so I suggest we start there...Big Bang and Cosmology, please...Edited by cavediver, : No reason given.