What book(s) would you all recommend for learning about these two theories? I have limited math knowledge; most of the equations I see look like a greek sentence to me. Is it even possible to really comprehend relativity without the math? I keep asking questions that turn out to be rather foolish, and I fear I'm trying the patience of those few here who can truly answer such questions. Efforts at reading online are proving to be problematic and even contradictory. For example, I read this statement: I believe Einstein gave up the ether concept and definitely opted for the physical relativity principle at least a couple of years before the final formulation of SRT, perhaps even earlier. At any rate, at some point well before the 1905 formulation of the theory, he made this choice and adhered to it thereafter. in How Did Einstein Discover Relativity<. Admittedly, this article is focused on atempting to answer "how", but nevertheless it does state that Einstein "gave up" on the concept of "ether" by 1905. And yet, Ether and the Theory of Relativity, apparently given by Einstein in 1920 clearly shows he at the least "allows for" the existence of ether, or "aether" as they put it. Point is, material I've been reading can be (apparently) contradictory. I cannot find online versions of Einstein's theories (at least not in English). So, what book(s) might I look for? And if math is essential to understand the theories, what math do I ned to learn? I have merely basic algebra to work with. What's the shortest path through calculus or whatever to understand the math required? Thanks in advance.