Why our universe is ever expanding. My own theory.

Maybe the universe is racing so fast and ever expanding because of Einstein’s theory of relativity.
Because of the curvature in space and time it means that heavy objects have strong gravitational curvatures they form, and these curvatures entail that all objects are constantly falling towards each other, creating an existing ripple effects that’s ever-pushing masses towards larger surfaces.
This could mean that there is a much larger universe that’s bending the parameters around it. This hence leads our universe to ever be in an expanding state.