[goatlover]

> Who cares if there's no gravity? Gravity wasn't sent down to us from heaven on a stone tablet, it's just a concept that lets us make predictions.

A concept that says gravity is the result of bending spacetime, with the speed of light being constant. It's not just a model, it's saying the universe is 4D spacetime, which explains why GR is so predictive.

[samloveshummus]

It is just a model though! Everything in science is just a model. We better hope it's just a model, because it's incompatible with quantum field theory, which is another very accurate model. The only consistent model that bridges the two, superstring theory, says that spacetime and gravity could fundamentally be many things, from closed strings travelling between D3-branes to the holographic projection of a conformal theory - and you still get the same predictions.