An article from Quanta Magazine (below) recaps the history of space-time symmetries in physics and how those symmetries have, in a sense, been simplified: Galilean (Newtonian) static, separate space and time. Relativistic “flat” space-time – Minkowski / Poincaré / Einstein. de Sitter spherical space-time: “… in the same way that the finite speed of light… Continue reading Universal symmetries – what really is broken?