On Oct 24, 2009, at 1:51 PM, Harry Veeder wrote:
----- Original Message -----
From: Horace Heffner <[email protected]>
Date: Saturday, October 24, 2009 11:43 am
Subject: Re: [Vo]:Gravity role in fusion
Masses do not react to potentials, they react to fields.
Gravitational fields superposition, just like Coulombic fields.
The
gravitational field intensity is zero midway between two equal mass
objects. Gravitational field intensity is zero at the center of
the
earth. If you are in a closed box at the center of a large planet
there is no way to tell you are not located out in space away from
any gravitational mass.
This is only true for a hypothetical "point person".
In practice a person has extension so each part of their body will
experience a net force and their body will expand slightly. The same
person out in space far away from any gravitational masses will not
expand.
I said "away from any gravitational mass. "Perhaps I should have said
far far away from any gravitational mass, far enough that tidal
effects are not detectable. I should have also noted that Einstein's
equivalence principle only applies for point masses, and that he was
well aware of tidal effects.
On the other hand, it is true for a person inside a hollow sphere,
since
the net pull of gravity everywhere inside a hollow sphere is zero.
Harry
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
