> Theoretical: a lot of these theories rely on people not understanding the domain of a function We thought it was an aberration of mathematics when Einstein's

> Theoretical: a lot of these theories rely on people not understanding the domain of a function We thought it was an aberration of mathematics when Einstein's equations blew up into singularities. A singularity couldn't exist in the real world, they said. Must just be an artifact of us using "real numbers", and we needed to be careful to respect the domains of those functions. Well, turns out singularities do exist and the math led us right to them.