Re: [Phys-l] definition of gravity

[John Mallinckrodt <ajm@csupomona.edu>]

Robert Cohen wrote:

> Follow-up question: does it matter whether I say "Earth's gravitational field" or "locally measured gravitational field"?  For example, is it appropriate to say the Earth's gravitational field is zero at the location of the space shuttle orbit?

No, it isn't because that statement implies that the gravitational field is not frame-dependent.  However, the gravitational field IS zero in all freely falling frames (which are necessarily "local," i.e. of sufficiently small extent to be able to neglect spacetime curvature) by definition no matter where they are.

John Mallinckrodt
Cal Poly Pomona