Re: Gravitational Radiation from the source

On Fri, Joe Fischer <efischer@xxxxxxxxx> wrote:

> This is about the early mention of gravitational
>gravity waves, or gravitational radiation.
>
> I don't know anything about gravitational radiation,

And I apologize for taking your time if LIGO happens
to produce results contrary to what I discuss below.

Note that my impression of the LIGO instrument
is that it does not have any antenna component that
is connected in such a way that electromagnetic or
magnetic attenuation would be detected, and no
induction or discriminator coils are used (except well
shielded optical to electronic circuitry to drive output
displays and recorders.


In the period 1911 through 1919, General Relativity
was in it's formation stage, and was lead by a number of
papers by Einstein, at least one or more co-authored by
others.
An earlier one co-authored with Gross man (an old
schoolmate of Einstein's) did not seem to create much
interest, but I am not qualified to comment on it's merits.

There is no way to know how many documents that
Einstein wrote, and especially working notes, that did
not survive or even may be in the archives but not of
interest in the view of the curators.

In my opinion, most of Einstein's writing was based
on good physics concepts. But in the period of the
development of General Relativity, even simple radio
frequency electromagnetism was in it's infancy, and
speculation about what new things it might apply to
had fewer constraints than today.

The early writings about gravitational radiation
probably are based on a stronger basis than I can
give them credit for, sorry.

I see clearly the reasoning in Einstein's Principle
of Equivalence and the superior logic of freefall being
inertial motion.
I do not understand the basis for gravitational
radiation, nor do I understand exactly what modern
physics expects them to be.

If gravity involved a real physical field like a
magnetic field, I could readily accept the concept
of gravitational radiation as a side effect.

I do not think any such "field" is involved with
gravity. Therefore my impression of what might be
expected of LIGO and other large detectors is very
biased, and the results should be limited to what I
would call "undulations" in matter.

These undulations should only exist as a result
of _changes_ in the motion of the "source" of the
gravity effects.
If the motion was simply linear (unaccelerated)
motion, like that of the planets, then the "frequency"
of the undulations should be very low corresponding
to the change in distance of the source from the
detector or the change in angle of the source.

This should mean that a symmetric explosion of
a star should not cause any appreciable change in
the mean/average distance of all the mass of the star.

Also, two stars colliding if both are moving
perpendicular to the line of sight might not cause
a change that could be detected.

A collision of a star moving away from the
detector with a "stationary" star could possibly
be detectable because the average mass of both
stars would then moving away from the detector,
but this might only result in one "undulation"
when the change in motion occurred.

Binary stars having a very long major axis
length perpendicular to the detector should
produce undulations of greater strength than
a major axis in the line of sight, or of close orbits.

Binary stars very close to the detector should
be a source of undulations corresponding to the
orbital frequency.
But binary stars or neutron stars in other
more distant galaxies would not present a major
axis subtending an angle large enough to produce
a strong detectable undulation in the detector arm.


In one of his papers, Joe Weber described a
laboratory gravitational radiation generator that would
have to spin at high RPM.
I do not understand why a higher RPM would
produce "stronger" gravitational radiation.

He also mentioned a piezo-electric gravitational
radiation generator, and that is also way over my head.
I do not think he meant piezo electric detection
of gravitational radiation.

I am writing this not because of what I think, but
because I am not sure what others think gravitational
radiation is or might be.

Joe Fischer

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