 Didn’t Einstein show that space and time are basically the same thing? It’s true that Einstein’s two theories of relativity radically altered our scientific picture of space and time, although it is more controversial what consequences the theories have for metaphysics. (See section 3 of the separate entry on  being and becoming in modern physics  for more detail on this issue.) It is the Special Theory of Relativity (STR) which has had most impact on the debate about temporal parts: three quite different arguments have been proposed, each of which purports to show that STR lends support to the perdurantist claim that things have temporal parts.