I probably could have been more explicit. To be clear, the opposites here are 'the big bang is an expansion of spacetime' and 'the big bang is an expansion in s

I probably could have been more explicit. To be clear, the opposites here are 'the big bang is an expansion of spacetime' and 'the big bang is an expansion in spacetime.' Swebs claimed the diagram showed the former, but it acually literally shows an expansion in space (which, it so happens, also works for an expansion of space, and so does not, as it stands, show a way to choose between the two.)