Gravity rules the universe at large and relativity explains it, but does so based on time and space not particles. Einstein concluded that the force of gravity isn’t a force at all, but just matter modifying the space and time that define movement. Gravity then divides physics into those that attribute it to graviton particles, and those that attribute it to space-time changes.
QR5.1.1. The Great Divide
QR5.1.2. Space and Time Change