Correct, it's all just spacetime. This is what Einstein was after in the last years of his life - a unified geometric theory, where mass was not separate from t

Correct, it's all just spacetime. This is what Einstein was after in the last years of his life - a unified geometric theory, where mass was not separate from the sheet, but rather, part of it - a deformation of it. [1] https://www.arxiv.org/pdf/0706.0190v2 https://www.arxiv.org/pdf/0706.0190v2 Water waves can crash into eachother. There's no reason that spacetime waves cannot either. You can get some hint of this if you look at the oscillations that comprise the Higgs field. The negative curvature of gravitation should be cancelled out by the positive curvature of matter and energy. https://en.wikipedia.org/wiki/Zero-energy_universe https://en.wikipedia.org/wiki/Zero-energy_universe