_Gravitational mass_ as described by Newton's Universal law of gravitation _is_ inertia in the first place. Newton derived his inverse square law from looking at the momentum of bodies in elliptical orbits, their geometry and applying Kepler's laws. However, for local gravity, where gravitating objects press on others, what Einstein was saying was that the pressures (stresses inside or between objects) are the same for gravitational or any other acceleration. But, actually, this idea is missing something.. Gravitational TENSION whilst in FREEFALL, which does distinguish gravitational acceleration from other accelerations.
_Gravitational mass_ as described by Newton's Universal law of gravitation _is_ inertia in the first place. Newton derived his inverse square law from looking at the momentum of bodies in elliptical orbits, their geometry and applying Kepler's laws.
However, for local gravity, where gravitating objects press on others, what Einstein was saying was that the pressures (stresses inside or between objects) are the same for gravitational or any other acceleration.
But, actually, this idea is missing something.. Gravitational TENSION whilst in FREEFALL, which does distinguish gravitational acceleration from other accelerations.
same is what i wanted to say