Re: GP-B Final results



On May 11, 1:37 pm, srp <srp2...@xxxxxxxxx> wrote:
On May 10, 5:48 am, "Ken S. Tucker" <dynam...@xxxxxxxxxxxx> wrote:









On May 9, 7:38 pm, John Polasek <jpola...@xxxxxxxxxx> wrote:

On Mon, 9 May 2011 18:07:25 -0700 (PDT), Eric Gisse

<jowr...@xxxxxxxxx> wrote:
On May 9, 11:15 am, John Polasek <jpola...@xxxxxxxxxx> wrote:
On Sat, 7 May 2011 07:20:07 -0700 (PDT), WalterOrlov

<wor...@xxxxxxxxx> wrote:
On May 5, 12:40 am, "Sue..." <suzysewns...@xxxxxxxxxxxx> wrote:
<<
NASA Headquarters Auditorium
300 E. Street SW
Washington, DC 20546-0001
Date: Wednesday, May 4, 2011
Time: 1:00-2:00 pm EDT

Final Results to be Posted on this Web Pagehttp://einstein.stanford.edu/highlights/status1.html

From the beginning the mission went wrong:

"The first analysis of this data revealed unexpected anomalies. The
gyroscopes had behaved badly - wandering around and pointing in
strange orientations. Irregular patches on the surfaces of the spheres
were to blame. Everitt knew about these patches and expected
interactions with the housing that would create small forces, or
torques. But unanticipated patches on the housing itself amplified
these electrostatic interactions. 'The torques were 100 times larger
than we were expecting,' says Everitt. 'It was a horrible shock.'"
http://www.sciencenews.org/view/generic/id/73870/title/Gravity_Probe_...

So, the error was 100 times the expected impact! Even for the amateur,
it is quite clear that the project failed. Today's jubilation over
alleged confirmation of general relativity is a mockery of the human
mind.

It is hard to understand how the team selected a perfect sphere to
represent a Gyro. The inertia tensor is completely degenerate-there is
no preferred axis. it would make the worst possible gyro. It's no
wonder they encountered a strange wandering about.

Absent other forces, it isn't going to wander. It would just spin in
place.

Of course it's not going to move laterally but the article pointed out
that it appeared to wander in angle at random just as if it were not
spinning.
Apparently they are not aware that that's because all the gyroscopic
forces self neutralize. A sphere is the worst possible choice for
gyroscopic action.

The ball has a tensor which can be shown as J times the identity
matrix
1 0 0
0 1 1 x J = J
0 0 1
If you apply arbitrary rotations R(A) the similarity transform, for a
second-rank tensor is, trivially,
-R[J]R = J
it is absolutely unaffected by the rotation and reduces to its
original native form.
In other words it doesn't matter how fast it is spinning, the sphere
itself can rotate independently, subject to random rotational drifts,
with zero gyroscopic consequences!
To me it appears that the experiment could not possibly have
succeeded.

John Polasek

Very little detail is available about the construction except to say
that it had no visible support and was kept centered
electrostatically. Nor any information as to how the data was read out
to the fantastic tolerances that are required.

Perhaps if you actually did a little reading on the subject.

The GP-B mission page has all that information.

Recall that with a degenerate inertia tensor the ball itself could be
turning as it pleased even despite the 4000 rpm. Since you can't read
the momentum vector how do you keep track of this thing?

An excellent question. Perhaps reading the website would answer it?

What is the form of the data that proves Einstein's dragging theorem?

There are many technical papers regarding this. Have you looked at any
of them?

Anyone who has had any experience with inertial guidance would know
that their ambitions far exceeded the possibilities.
John Polasek

You make a lot of good points John.
It is quite true that the apparatus in the experiment must be
well defined, and the experiment repeatable.
The sphere would oblate when spun, and of course, they can't
be perfectly homogeneous, and in turn that will cause vibration.
On Earth's surface we have good inertial guidance systems,
I think we should figure out how to make terrestrial surface
based experiment for economics and repeatability.
Let's respect the taxpayer.
Ken S. Tucker

Not a word either about the Moon gravity and Sun gravity that
are likely to have cyclically affected the experiment.

André Michaud

Ok, calculate the effects of the moon and the sun on a test body in
Earth's orbit.

A purely Newtonian calculation would be a more than acceptable opener.
The perturbation is going to be very small, if at all relevant. So you
can use classical perturbation theory and any further approximations
you wish. I just want to see you quantify the effect.

Plus, do you know what was actually measured? Be sure to get the right
answer on that.
.