Spacetime

Spacetime is the four-dimensional manifold proposed by current physics as the arena for Nature’s show. Although Newtonian physics can very well be reformulated in a spacetime setting, the idea of spacetime was not developed until the twentieth century, in connection with Einstein’s theories of special and general relativity. Due to the success of special relativity in microphysics and of general relativity in astronomy and cosmology, every advanced physical theory is now a spacetime theory. Spacetime is undoubtedly an artificial concept, which our hominid ancestors did not possess, but the same is true of Newtonian space and time.