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Figaro
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From the weak EP, inertial mass is equivalent to the gravitational mass. The weak EP implies the universality of gravitation. Some implications of the EP are:
1) Gravity is inescapable - there is no such thing as gravitationally neutral object with respect to which we can measure the acceleration due to gravity so acceleration due to gravity is not something that can be reliably defined.
2) Gravity is not a force, a force is something that leads to acceleration, and the definition of zero acceleration is moving freely in the presence of whatever gravitational field happens to be around.
1) If acceleration due to gravity is not something that can be reliably defined, what about 9.8m/s^2?
2) I know that gravity is not a force but how do we resolve the usual way of calculating the "force due to gravity" and "acceleration due to gravity" as in some general physics books? I know that these are due to the equivalence of inertial mass and gravitational mass but can someone expound on it?
Reference: Spacetime and Geometry by Carroll
1) Gravity is inescapable - there is no such thing as gravitationally neutral object with respect to which we can measure the acceleration due to gravity so acceleration due to gravity is not something that can be reliably defined.
2) Gravity is not a force, a force is something that leads to acceleration, and the definition of zero acceleration is moving freely in the presence of whatever gravitational field happens to be around.
1) If acceleration due to gravity is not something that can be reliably defined, what about 9.8m/s^2?
2) I know that gravity is not a force but how do we resolve the usual way of calculating the "force due to gravity" and "acceleration due to gravity" as in some general physics books? I know that these are due to the equivalence of inertial mass and gravitational mass but can someone expound on it?
Reference: Spacetime and Geometry by Carroll