> But, I don't buy the argument made here: > > To call gravity a force, is to privilege flat space as somehow being special. > Flat space is special, and we d

> But, I don't buy the argument made here: > > To call gravity a force, is to privilege flat space as somehow being special. > Flat space is special, and we didn't make it special. Neither is curved spacetime. Metrics like the Schwarzschild metric merely let us map between the two. They inherently do this, so flat spacetime seems like inherently as real as -no more, and no less than- curved spacetime. And in flat spacetime gravity is very much a force. We should really not teach that gravity curves spacetime, but that there are equivalent representations of what massive objects do to their surroundings. The reason we should teach both alternatives is that humans have a hard time wrapping their minds around "curved spacetime". Giving a person two different ways to think about the same effects will increase the likelihood that they will understand, and only at a very small cost of increased cognitive load (but since understanding eases the cognitive load, the overall effect should be to reduce cognitive load). Pedagogy matters.