Re: The Laws of Intelligence Examined

Tom Van Flandern:
David A. Smith writes:

[DASmith]: I was not discussing "speed of gravity", but your
misrepresentations of GR.

And I was explaining that there is more than one physical
interpretation of GR.

No, there is not, tom. General relativity is a geometric theory
of spacetime - by design.

You are clearly only familiar with the geometric
interpretation, in which gravity is not a classical force. There is also a
field interpretation of GR used most commonly in celestial mechanics, my
field of specialization, in which gravity remains a classical force.

Try again, tom. The field to which you refer happens to be the
connection coefficients. General relativity is not a classical
force.

[...]
Feynman stopped at saying your preferred geometric interpretation
of GR was "not needed, just marvelous".

Feynman also said that a very long time ago at a time when quantum field
theories were beginning to have incredible success as theories of the
strong, weak and electromagnetic interactions during a time that general
relativity had not made a lot of progress. He, (and as far as I know) most
of the other particle physicists of that same era expected gravity to
follow suit. That did not happen and during the interim, a great deal has
been learned about both quantum field theory and general relativity.
Perhaps you should get caught up. The bottom line is that if you interpret
general relativity as a field theory, the field carries the curvature via
the connection coefficients. You can easily compare general relativity
with the field theories in the standard model by simply noting that the
curvature tensor in general relativity, the electromagnetic, weak and
strong interactions are _all_ given by the commutator of the covariant
derivative which includes the connection for the respective field. Your
distinction is without a difference. In fact, your distinction is made out
of (even greater) ignorance in the subjects you are trying to use for
comparison.

Vigier and I went
farther and said the geometric interpretation obscures the physics of
gravitation because it provides no cause to initiate motion and no source of
new momentum. ["Experimental Repeal of the Speed Limit for Gravitational,
Electrodynamic, and Quantum Field Interactions", T. Van Flandern and J.P.
Vigier, Found.Phys. 32:1031-1068 (2002)]

That has to one of the most inane conclusions you've ever drawn.
To use your own non-sequiturs, you only need to invoke forces and
``causes'' to ``initiate motion'' if you impose you own personal
ideology of the geometry such that you require those things. Sheesh...


So it will get us nowhere for you to keep repeating "That's not
right because that isn't what I was taught." But we can make progress if you
can address the substance of the problems I've mentioned with the geometric
interpretation.

So long as you continue to misconstrue your misunderstanding as a
different interpretation, despite having your misconceptions pointed
out _repeatedly_ to you, you shouldn't be lecturing anyone on ``making
progress.''

[...]

Please don't reduce these important distinctions to semantics.

You are the one who has reduced it to semantics.
[...]

[DASmith]: [In Feynman's quote], gravitation is presented not as a force,
but as a field invoking exchange particles.

"Field" means gravitational potential field. The nature of this
field is still debated. But if momentum-carrying particles are involved (as
the source of the new 3-space momentum transferred to target bodies), they
are applying a force to the target body by definition or 3-space "force":
the time rate of change of momentum. In gravitation, force is also the
gradient of the potential, so "field" (meaning potential field) also implies
force in that sense too.

No, it doesn't. You apparently do not know the difference between a field
potential and a newtonian pothential function. The two are not the same
thing. A potential in field theory _is_ the actual field. For example in
E&M the potential is four-potential, A^u. It has both time and space
components. In geometric language, the coonection coefficients, A_u and
the partial derivative together (i.e., the covariant derivative) is a
connection on a fibre bundle. In general relativity, the potential
(i.e.,gravitational field) is the christoffel symbols (connection
coefficients). The partial derivative together with the connection
coefficients (i.e., the covariant derivative) is a connection on a tangent
bundle. The curvature tensors are otained the same way in each case.
Take the commutator of the covariant derivatives.


[...]

[DASmith]: Not really.

Okay, then please explain the physics that causes the 3-space
acceleration of a target body toward a source mass, and the details of the
momentum transfer from source to target.

That is _your_ problem, since _your_ misconceptions are the source
of your question. I'll put it in perspective. Do you have any real
problem understanding that you and your buddy vigier could both walk
in opposite directions starting from the north pole at a constant speed
and end up walking toward each other at the south pole? Now, if neither
of you experienced any forces, then precisely how did you manage to
end up walking toward each other? Does this ``dilemna'' cause you a
lot of anguish? If someone kept insisting that a force was necessary
to cause the acceleration that changed your direction, because the earth
is flat, about how many times would you be willing to explain why that
argument is non-sensical if the person stops insisting the earth is flat
and tries to imagine the earth as round?

If you picture _yourself_ as the ninny who insists that proponents
of a round earth explain the force that causes people to change
directions because he refuses to picture the earth as not being flat,
(despite claiming otherwise), then you have the situation with you
and general relativity. You refuse to picture the universe as general
relativity depicts it (despite all of your bull*** claiming otherwise),
and your arguments are arguments against your own misconceptions.

[...]

You left it ambiguous whether you do accept that gravity is a
classical force in 3-space relativistic physics, or whether you dispute
this. Elsewhere, you appear to dispute it.

Your ``three-space relativistic physics'' is known as galilean
relativity. While newtonian gravity is a theory of gravity that
can be formulated in a galilean spacetime, newtonian gravity is
known to e incorrect.

[...]
[DASmith]: Right. What orbits with the bodies is the "spacetime effects"
they individually create. No need for any sort of propagation for
"ordinary effects".

This runs up against the physics-based objection to the
geometric interpretation of GR. Your description requires magic. Not even a
rigid rod can move as a singlet body when a force is applied to some part of
it. The force merely starts a pressure wave traveling at the speed of sound
along the rod (or through the body), and the far end of the rod (or body)
doesn't respond until the pressure wave gets there.

And your point is what?

The fact that this
occurs too fast to see for most materials should not deceive us into
thinking there can be instantaneous action at a distance, as would be
required by your description.

Tom, some people consider the possibility that others employ some
intelligence when reading a reply and make an attempt to get the
point rather than deliberatly miscontrue anything allowed by the
semantics. You asked for a qualitative description and he gave you
one. Now, you want to play semantics games. There is no magic here
any more than a round earth makes it possile for parallel lines
to intersect -- just your own copious outpouring of legerdemain.

[..shovelled away..]

[DASmith]: You are speaking of specific solutions, "approximations" if you
will, to GR. Not GR itself. Newtonian gravity is one such approximation.

And your point is ... ? If these "approximations", which may be
made as exact as we please, are not representative of GR, then GR has never
been tested.

So then, is it your contention that newtonian gravity and newtonian
physics has never been tested because the only tests that have ever
been done have been against approximations? Last time I checked, the
N-body problem was still intractable, so according to you, it is obviously
impossible to determine whether or not newtonian physics can make
any testable predictions about the solar system. According to your
argument, no theory could have ever been tested nor could any theory ever
be tested. That would seem like a good reason for you to take up a
different hobby.




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