(Carlos L) wrote in message . com...
(Andr? Michaud) wrote in message ...
(Carlos L) wrote in message ...

Note: I posted this 5 days ago but since that post has not appeared I
remove the follow_ups to sci.physics.research and sci.astro research
and I post it again (because I don't want to leave the impression that
I've been convinced that my ideas on this issue have been proven
wrong).
----------------------

These monitored forums are reserved for discussions on currently
accepted orthogox theories and ideas that can be directly related
to them.

No other ideas will be discussed.

Thanks André for having looked and for your comments about my
non-orthodox explanation that was posted in the thread "Pioneer
Anomaly" URL: http://groups.google.com/groups?selm...g.g oogle.com

Here is my comment. It is pretty well established without any
doubt that the speed of light of photons is invariant in vacuum
and completely independant of the velocity of the source, which
is precisely why Doppler ranging can be used at all.

I know "that" and I believe it is true. Unfortunately everybody finds
difficult to understand my (very simple) interpretation of the
constancy of the speed of light in vacuum. (It must be that I don't
explain myself clearly enough). I try again:
I do believe that the speed of light is independent of the speed of
the source. But I believe that the speed of light in vacuum is always
c *relative to the physical apparatus* that detects it.

Isn't that somewhat contradictory with what you say in the previous
sentence?

You do imply here that velocity c of EM energy, although independent
of the source (which implies that c may be an absolute velocity for
EM energy in vacuum), would not be independent of the velocity of
a physical apparatus that would detect it.

That's what brought my comment. If c were an absolute velocity in vacuum
for EM energy, it seems to me not to be reconcilable with the idea that
it could at the same time be relative to an apparatus that may itself
have a velocity. I would agree if said apparatus could be immobilized
with respect to vacuum, but how could this be achieved?

Aren't we confronted here whith the age old lack (or perceived lack) of
an absolute reference with respect to which such zero velocity could
be achieved in vacuum?

The speed of
light will also be c relative to the reference frame of description if
the detector is at rest in it (as is generally the case). But since SR
does not dare forbid to use detectors that move relative to the
reference frame of description, I assume that in these cases the speed
of light will no longer be c relative to the frame of description
(until some experiment, in vacuum, proves me wrong).

I see your point, but ref to my interrogation above.

An implication of
such interpretation is that since "all" detectors, whatever their
speed relative to the source, are known to receive light from moving
sources it must be assumed that a typical source emits light-type
disturbance at a continuum of speeds.

Your postulate seems to imply this of course, but I personally lean
towards concluding, from all experimental evidence that I considered,
that c would be an absolute velocity in vacuum, unless experiments
could show otherwise.

(I don't want to discuss in this
thread the details of the *other* implications or problems with this
idea). My hope here was to find some reader able to believe in the
possibility that such idea is compatible with the experimental facts
and be willing to discuss my interpretation of the Pioneers anomalies.

I would be willing to discuss but I must say that I have been convinced
for long time that velocity of EM energy is invariant in vacuum and not
relative to any source or observer.

As for the doppler data, if it were not to be trusted in this case,
this would make this case the only one on record where Doppler data
would be found not to be totally precise.

I also believe that this case (of the Pioneers) is indeed the first in
which the Doppler data do not agree with the expected position of a
body governed by the very trustable celestial mechanics laws.

Trustable only in light of what we knew before.

Consider that both Pioneers are the first small bodies that have
been sent on hyperbolic escape trajectories from the Solar system
with us receiving EM signals from them for quite a while.

This is the first data available for small bodies on such trajectories.
I am not that surprised that our physics theories (classical as well as
relativistic) may not be able to predict with precision observed
behaviour that could be observed only in such cases and that had not
been observed before.

But this
is a special case because, for the Pioneers: (1) the position (as a
function of time, therefore including velocity, acceleration, ...) is
(supposedly) known with enormous precision

As I said, according to the state of our theories, which are based on
the only data that was available previously.

and the experimenter is not
allowed to say "the disagreement with our Doppler data must be due to
our imprecise knowledge of their position".

If the Doppler data is ok, then I say our theories simply need to be
reconsidered in light of this new data on top of all previously verified
data.

(2) the velocities of the
observed bodies (the Pioneers) have a "big" component v along the line
of sight, and according to my interpretation, the effect is
proportional to such component.

Yes, making the Doppler data all the more significant in my view,
almost "ideally" significant.

That is not the case for the moon that is AFAIK the only other celestial
body whose position is known with such precision.

And that are not small bodies on hyperbolic escape trajectories.

To my knowledge, all cases where verification by other means could
be used, the precision cannot be questioned.

I believe that also.

When orthodox theories can't explain some phenomenon, it is common
practice to distrust and finally discard the data as being tainted.

Well, after having studied and discarded all other "reasonable"
explanations, I suppose that it is the best thing to do.

It is one option of course. But in view of the fact that it is the
first time in history that we lay hands on Doppler data (that in all
other cases proved trustworthy) from small bodies sent on hyperbolic
escape trajectories, I lean rather towards thinking that our theories
simply need a long overdue final shake down to integrate and explain
coherently this behavior in light of all that we now know.

Mine has not been contradicted yet except by you that has not fully
understood it, (my fault). But anyway, thanks again.

Maybe I understood your view.


Carlos L.

André Michaud