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**Starblade Darksquall**

(Gordon D. Pusch) wrote in message ...
(Starblade Darksquall) writes:

There seems to be a very big split between those who beleive that
gravity is a force between two bodies mediated by the graviton 2-boson
and can be unified with the other forces, and those who beleive that
gravity is the bending of timespace, and that freefall can be taken to
be a proper reference frame.

There is no such "conflict," any more than there is a "conflict" caused by
a quantum-mechanical object exhibiting both "wave-like" and "particle-like"
properties. The "particle" picture is what is appropriate when one is
discussing quatum particles exchanging a small number of gravitons,
so that quantum effects are important; the "curved spacetime" picture
is appropriate in the classical limit when one has a huge enough number
of gravitons that one can approximate them as a classical "field."
A proper quantum theory of gravitation and spacetime will presumably
smoothly interpolate between these limits, just as quantum mechanics
smoothly interpolates between "particle-like" and "wave-like" behaviors
as the allowed resolution of the measurement apparatus is dialed from
"fine" spatial resolution (and necessarily coarse momentum resolution)
to fine momentum resolution (and necessarily course spatial resolution).
The "loop-space approach" to quantum fields being pursued by Lee Smolin
and others is perhaps a crude initial attempt at such a description.

But there is a test we can do which will distinguish between them.

Sorry, no.

If gravity is a force that can be mediated by graviton particles, then
in a non-free falling reference frame, Newton's laws would be
preserved. This means anything that can be effected by gravity also
has a gravitational effect on the first object. Since we all know that
light is effected by gravity, then analogously it ought to have a
gravitational field, so that Newton's laws are then correct in a
regular inertial reference frame.

However, if gravity is the bending of timespace, and is a natural
state of motion like inertia, then Newton's laws would only be
conserved in a state of free-fall. Newton's laws would be preserved in
a reference frame of free fall. Since light falls with a constant
acceleration, then it would not be required to exert a gravitational
force on anything in order to preserve Newton's laws, and therefore it
would not have a gravitational field of any sort.

Sorry, it doesn't work that simply. A beam of light only exerts
"no gravitational force" on _another beam of light traveling in
the same direction_. On a massive particle, it exerts =TWICE=
the "gravitational force" one would naively calculate by Newton,
just as it experiences =TWICE= the gravitational deflection that
one would naively calculate by Newton --- and two light beams
traveling in opposite directions each experience _FOUR TIMES_
the "gravitational force" and gravitational deflection one would
naively calculate using Newton.

All we have to do, then, is determine whether light exerts a
gravitational force on things around it. Then we could determine
which of the models is correct and which is incorrect.

This experiment has already been done: Since a photon is deflected by
=TWICE= the angle one naively expects from Newton, by conservation of
momentum (which still holds in relativity), the Sun must have experienced
an _EQUAL AND OPPOSITE RECOIL DUE TO THE GRAVITATIONAL FORCE THE PHOTON
EXERTED ON IT_ --- and again, this recoil is =TWICE= as large as Newton
would have naively predicted. If this recoil did not occur, conservation
of both momentum and energy would be violated, and it would be possible
to build both reactionless drives and perpetual motion machines by
directing photons past masses --- and no one except crackpots take
either of those possibilities seriously !!!

Note, BTW, that the factor of =TWO= in the deflection calculation results
because of _SPACETIME CURVATURE_ by the mass of the Sun. Particles moving
at nearly the speed of light "feel" both the spatial and temporal components
of the curvature tensor, whereas "slowly" moving particles "feel" only the
temporal component. The deflection smoothly interpolates from "Newtonian"
to "double-Newtonian" as the "test particle" approaches lightspeed relative
to the gravitating source.

-- Gordon D. Pusch

perl -e '$_ = \n"; s/NO\.//; s/SPAM\.//; print;'

Alright, so now what? Does that mean if matter goes fast enough, it
has twice the gravitational attraction to other objects? That G
ultimately depends on speed? Then how do you reconcile this with the
equation for gravity? What is the REAL equation for gravity then?
Something like F = GM1(1+per1)M2(1+per2)/r^2sqrt(1-S/r) where per1 is
the percentage of matter that is in energy form in the first particle,
per2 is the percentage of matter that is in energy form in the second
particle, and S is the Schartzchild radius?

I mean, it would HAVE to be something weird like that!

Do you have the 100% RELATIVE TO THE TOP NOTCH SCIENTISTS equation for
gravity for every type of thing that they know? Or are you just
another crank, pretending that you know as much as them?

(...Starblade Riven Darksquall...)