Originally Posted By: Orac
Absolute gravimeters, which nowadays are made compact so they too can be used in the field, work by directly measuring the acceleration of a mass during free fall in a vacuum, when the accelerometer is rigidly attached to the ground

A gravimeter is not an accelerometer. A gravimeter is used to measure the force of gravity at a place on the surface of the Earth. They may include accelerometers but they aren't accelerometers. Don't try changing the rules of the game in the middle.

Bill Gill

C is not the speed of light in a vacuum.
C is the universal speed limit.