Re: "Is There a Force of Gravity?"




Sue... wrote:
Tom Roberts wrote:
Koobee Wublee wrote:
On Nov 27, 2:11 pm, Tom Roberts <tjroberts...@xxxxxxxxxxxxx> wrote:
There are literally hundreds of experiments that support and confirm SR,
and many of them refute Newtonian mechanics. Look in the FAQ for references.

This is not true. There are no experiments out there that completely
support SR.

You are wrong. Look it up. <shrug>


However, there are plenty of experiments out there which
agree with the Lorentz transform but not its immediate reciprocal form
which is also the Lorentz transform. To agree with SR, you need an
experiment that show both the Lorentz transform is true as well as its
reciprocal form. <shrug>

You clearly do not know how theories are tested in physics.

There are plenty of experiment that support SR 1920.
But they are not the cranky ones listed in the FAQ
Many are specifically designed to exploit well known
errors in the 1905 paper.


"The Incompatibility of the Law of Propagation of Light
with the Principle of Relativity" is ONLY apparent.
http://www.bartleby.com/173/7.html

PERIOD.


Sue....


This is so fundamental mistake and shows why the man was a crank.

"But this result comes into conflict with the principle of relativity
set forth in Section V. For, like every other general law of nature,
the law of the transmission of light in vacuo must, according to the
principle of relativity, be the same for the railway carriage as
reference-body as when the rails are the body of reference. But, from
our above consideration, this would appear to be impossible. If every
ray of light is propagated relative to the embankment with the velocity
c, then for this reason it would appear that another law of propagation
of light must necessarily hold with respect to the carriage-a result
contradictory to the principle of relativity."

In order to prove universal compatibility, one must prove there is no
case of conflict under any conditions. It is not merely enough to show
a case of agreement. Example of conflict: twin paradox.

This illustrates the major problem of all cranks: no adherence to
logical principles. Actually, he got his agreement because he used
Galilean velocity addition. When he uses the relativistic velocity
addition formula he gets the conflict in twin paradox.


Mike






Time-independent Maxwell equations
Time-dependent Maxwell's equations
http://farside.ph.utexas.edu/teaching/em/lectures/lectures.html

Weber knew that because his field equations were relativistic.

Sue...
http://wwwcdf.pd.infn.it/~loreti/science.html
http://www.quackwatch.org/01QuackeryRelatedTopics/pseudo.html





There are dozens of experiments that support and confirm GR, and most if
not all of them refute Newtonian mechanics. Look in the FAQ for references.

Most of all these experiments are faulty. For examples, [...]

Your first two "examples" are the earliest tests, which have since been
repeated with vastly better resolutions and/or accuracy. Your statements
about geodesics are complete and utter nonsense.


But ultimately the equations of motion come from the Einstein field
equation:

G = T G is the Einstein curvature tensor, and T is the
energy-momentum tensor; units are such that c=1
and 8*pi*k=1, k is Newton's gravitational constant.

The Einstein field equations only allow one to solve what the metric
is. These equations do not deal with the geodesics directly.

You CLEARLY do not understand this. For starters, the geodesic equation
follows directly from the field equation, when applied to test particles
(the only particles for which the geodesic equation is valid). In any
case, the field equation determines BOTH the metric and the
energy-momentum tensor, and the latter includes how all objects and
fields in the manifold move and interact.


They are actually not difficult to solve if assuming a diagonal metric
in spherically symmetric coordinate system where the orbital motion is
confined to the equatorial plane.

As I said, "simple systems with lots of geometric symmetries". What you
said is completely unrelated to the spring-mass system I was discussing
-- it is NOWHERE CLOSE to "spherically symmetric", and quite clearly
does not have a "diagonal metric" in any sensible coordinate system that
includes the whole thing.


> [... further outrageous nonsense, such as claiming the Riemann
> tensor was "designed by Ricci"...]


Tom Roberts

.