strong equivalence principle

The strong equivalence principle states that the laws of physics, including gravity, are the same everywhere and in all circumstances, whether you're in a gravitational field or accelerating through space. It extends Einstein's idea that local experiments can't tell the difference between being at rest in a gravitational field or accelerating in empty space, to include not just test particles but also the influence of gravity itself. Essentially, it means gravity affects everything uniformly and that local experiments in freely falling reference frames cannot distinguish between uniform gravity and motion in gravity-free space.