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From: Tom Roberts on 16 Mar 2010 14:50
John Duffield wrote:
>> RVHG: And what about the electric force between two charged entities? It is also a "pseudoforce"
>
> I wouldn't call it that myself. But if you've got a system consisting
> of an electron and a positron accelerating towards one another,
> conservation of energy tells you they can't give each other more
> energy.

Indeed, due to radiation they "give each other" less energy. In any case,
electric force is not a pseudo-force.


A pseudo-force, aka fictitious force, is something like centrifugal and Coriolis
"forces" -- not any natural phenomenon, but rather an artifact of a human choice
of coordinates. In GR, "gravitational force" is fictitious in exactly the same
way. The word "force" in these names is an anachronism.

Stated differently, the equation of motion in GR for small pointlike objects is:

D/d\tau P = F [D/d\tau is the covariant derivative wrt the
object's proper time, P is the object's
4-momentum, and F is the force on the object]

Forces appear on the RHS, while centrifugal, Coriolis, and gravitational
"forces" appear on the LHS, buried inside the covariant derivative. In
particular, the former are necessarily 4-vectors, while the latter are not
tensors at all (they are components of the connection).


Tom Roberts
From: mpc755 on 16 Mar 2010 15:05
On Feb 16, 11:10 am, "Liater" <lia...(a)verizon.net> wrote:
> v

The pressure associated with the aether displaced by massive objects
is gravity.
From: BURT on 16 Mar 2010 17:20
On Feb 16, 9:50 am, John Duffield <johnduffi...(a)btconnect.com> wrote:
> Yes, there is a force of gravity. But it isn't the same kind of force
> as when you push an object to make it move. In the latter situation
> you are transferring energy to the object. Gravity doesn't do this.
> Instead it converts potential energy into kinetic energy, and is
> sometimes called an "internal force" as opposed to an "external
> force". It's also sometimes called a "pseudoforce", but definitions
> can be ambiguous and the subject of debate.

Some mass becomes acceleration. Mass becoming motion energy that is
conserved.
Energy is pushed faster into slower time.

Mitch Raemsch
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