>>11787381einstein would have said that space is basically the manifold described by the metric tensor, and the metric is the fundamental thing, and the metric is basically dictated by the presence of mass/energy plus the cosmological constant plus possible boundary conditions that can have nontrivial topology. so in other words, space is not a fundamental entity but emerges in the relationships of matter and topology and possibly the cosmological constant and boundary conditions .
string theory says the same thing in a lot of ways, but it makes things a bit more explicit. the background metric tensor is represented by a coherent background of gravitons. the gravitons represent a normal strong state and the einstein equations are just an emergent sector of the theory of strings. so in string theory, space is just an emergent aspect of the interactions of fundamental strings
