Re: Tom Van Flandern and Newtonian Gravity

From: Mike (eleatis_at_yahoo.gr)
Date: 08/12/04 

Date: 12 Aug 2004 04:25:08 -0700

"Tom Van Flandern" <tomvf@starpower.net> wrote in message news:<411ab962$0$5896$61fed72c@news.rcn.com>...
 
> and "Mike" <eleatis@yahoo.gr> writes:
>
> > [Mike]: He [tvf] uses the silly rubber *** analogy in an attempt to
> convince laymen that a force is required to initiate motion in GR.
>
> I use only the "no magic allowed" axiom of physics.

This axiom you refer to cannot be one of physics but of metaphysics.
Please try to understand the difference otherwise we cannot have an
intelligent discussion. What do you mean by the world "magic"?
Aboriginals thought that flying planes above Australian desserts were
some kind of magical things. Is that you notion of magic? Something
you cannot comprehend?

> The
> rubber *** analogy works as an analogy for explaining why a force is
> needed just as well as it worked as an analogy for how GR explains
> gravity. But in both cases, the absence of a source for new momentum for
> the target body and the absence of a transfer mechanism for this
> momentum can be explained in only two ways: (1) a force acts ("force"
> being defined as "the time rate of change of momentum"); or (2)
> mathematical magic.

Read GR gain and try to understand that 4-momentum time rate of change
is zero in geodesic motion in 4-space. I hope you know that is the
time rate of change of something is zero, that something has a
constant value and it does not increase of decrese in time.

>
> But perhaps you have a third way that no one else has yet
> thought of? Before you repeat your misunderstanding of what "spacetime"
> is, I suggest you read my article "Does space curve?" (which
> demonstrates what spacetime is in physics), and refresh on the physics
> definition of "force".

You do not accomplish anything by stating this non-sense and making
these remarks. You have no clue of what the term "spacetime" stands
for and you have proved that.

>
> > [Mike]: Thus, he [tvf] uses curved space to argue about curved
> spacetime. Obviously wrong.
>
> Let me get this straight. Bilge and I are having a
> discussion about my article in which I demonstrate that curved space
> plays no role in GR or in "curved spacetime"; and Bilge disputes me on
> that point, maintaining that space and its curvature do play a role in
> curved spacetime. But you are now criticizing *me*, not Bilge, for
> trying to use curved space in GR?

Obviously Bilge is right and you have gross misconceptions even about
the point of the discussion. Obviously curved space plays a role but
NOT the one you attribute to it ot claim it plays or use to justify
you naive theories.

>
> If I have that right, I'd be forced to conclude that your
> comprehension levels are low. Please tell me that you just got your net
> personalities mixed up, or had a brief brain lapse.

Ad hominenation will get you nowehere. I mean nowwhere.

>
> > [Mike]: He [tvf] assumes that the object magically appears suddenly on
> his silly rubber *** and needs then a cause to move.
>
> Where did this come from? I was discussing the 3-space
> trajectories of real objects such as comets. If we start them from the
> stationary point on a linear orbit straight into the Sun, what initiates
> motion?

I will now start wondering about your skills. How in the world can you
start from some "statiobary" point? Is there such a point? Is there
such a thing as a linear orbit in 3-space?

But to answer your questions, in GR there is no requirement for an
agent to initiate motion. Motion is always there at all times. It's
your thought experiment that is silly.

> And what difference does it make if the comet was injected into
> that linear orbit by the passage of a star, or it a spaceship dropped it
> off there? The same physics question exists either way.

Red herring

>
> > [Mike]: The point is that every body in spacetime already exists and
> has a trajectory already uniquely defined.
>
> All physical bodies in orbit have an initial point in time
> before which they did not exist in their present form, or were not yet
> in orbit.

Are you implying there were not "substance" but 'spirits"? I see...

> Suppose an asteroid is resting peacefully by itself in deep
> space relative to the distant stars...

Sorry, but I cannot suppose these things. These are wild dreams devoid
of any physics context.

> then suddenly a planet ejected from
> a distant solar system during a nova explosion comes rushing by and .
> Well, I can't say "applies a gravitational force to the asteroid"
> because you don't seem to accept the physics definition of force.

If you pay attention to me and others in here you will understand that
no one is disputing the definition of force, the known correleation
beteen it and time rate of change of momentum. Current physics has
advanced enough to question the causal connection between dp/dt and F.
Obviously, you have not remained current and you are still stuck with
the causal interpretation, which by the way will gets you nowhere.

> But
> surely something happens to the location of the asteroid in 3-space
> relative to the distant stars. Please describe that something and what
> makes it happen if there is no force applied. (Hint: In physics,
> curvature alone cannot initiate 3-space motion unless a force acts.)
>

Your hint is good for a TV show but ridiculus as far as physics and
its current advanced state.

> > [Mike]: Another simple fact that Van Flandern does not understand is
> that geodesic motion is inertial motion in 4-space where Newton's first
> law holds, i.e. no forces are required for it. He argues what happens if
> projections in 3-space are taken. The answer is that GR does not hold
> any longer and he is left with Newtonian mechanics and the problem of
> causality and fictitious forces needed to explain motion in local
> non-inertial frames of reference.
>
> Congratulations! In one sweeping statement, you just wiped
> out the entire field of relativistic celestial mechanics, which takes
> place in 3-space.

No Sir, relativistic celestial mechanics takes place in 4-space.
Otherwise it cannot be called relativistic. It is called Neo-Newtonian
in the best case.

> I suggest you crack a book and get up to speed. If GR
> did not apply in 3-space, where all observations are made, then it would
> be an observationally untested theory.
>

This is another fallacious argument of yours, that of disconected
premises and conclusion. A non sequitur. Measurements in three space
are made in a way compatible with the theory using clocks and rulers.
That does not alter the foundation of the theory but only used to
verify its predictions.

> You almost seem to be arguing that 3-space is not reality.
> Are you perhaps a 4-space being, forever unchanging? :-)
>

I noe see your metaphysical confusion. You are arguing in terms of a
preconceived idea of what constitutes reality. This is not the subject
of physics but that of ontology, a subject of metaphysics. I have
suggested to you in tha past to avoid ontology and stick with
epistemology at best. You ignore the suggestion.

It remains for you to answer the questions you keep avoiding while
resoring in your agly ad hominen attacks: Tell me, how does you Meta
Model justifies the need to consider ficticious forces in local
non-inertial reference frames in your 3-space. Are those ficticious
forces, like the centrifugal, real for you? Abswer of you have what it
takes to be a serious scientist.

Mike

Quantcast