Ranging and Pioneer

John (Liberty) Bell wrote:
wrote:
..
The anomaly was observed for 20 years, thus giving an accumulated
round trip difference of ~ 400,000 km hence time difference of
1second.

The first report I have seen of the anomaly is gr-qc/9808081
and their last contact was in January 2003. If they had tried
your method as soon as the anomaly was seen as being
real and not just a flaw in the analysis, the best they could
get was less than 5 years and the last decent signal was
April 2002.

This makes the timing constraint somewhat more relaxed than you suggest
here. Furthermore, although an accurate figure for this distance
discrepancy would be ideal, it is only necessary to establish whether
there is any unambiguous distance discrepancy or not, within the
available timing uncertainties, in order to answer the question of
whether the apparent anomalous acceleration had real consequences or
not. This, I suggest, makes any total timing uncertainty of 1 second
adequate for answering that question.

They would need at least three readings (at best 2.5 years
apart) to separate a real acceleration from an error in the
initial vector, and timings in the 10s of ms or better would
be needed.

and remember that signal
was being sent from one station, say Madrid, and
the loss of signal detected at another, for example
Canberra, and millisecond accuracy would have been
needed at both ends.

Why?

Why two stations? Because the Earth rotated during the
signal flight time. Why millisecond accuracy - see above.

Finally you have perhaps the biggest problem of
measuring the switch-off of the signal with millisecond
accuracy through a receiver chain with a bandwidth of
less than 1 Hz which is what was needed to hold lock
on the carrier. That applies whichever method of timing
you use at the transmitter.

A 1 Hz bandwidth allows a signal to pass from maximum to zero and back
again in 1 second. This suggests that detecting a change from maximum
to zero in ~ half a second is, in fact, perfectly feasible with such a
receiver chain.

The problem isn't the speed as such, with a perfect
signal you can set the threshold at say 50% and
know the timing quite accurately. The problem is
that there is noise present too. You are hitting the
time-domain equivalent of Shannon's Theorem.

(Possible phase shifts implicit this close to the
bandwidth limit are not a problem since a Pioneer response can be
mocked up on Earth, and tested through that receiver chain to determine
in advance what that phase shift will be.)

Phase shift isn't a problem you are looking at the
output of an rms power detector for a "sudden"
reduction in (signal+noise) level.

Thanks for your additional comments.

Pleasure. I'm not really knocking your idea but rather
trying to show the problems that need to be worked
round. If you find a solution to the bandwidth problem
I would love to know it, it's a frequently encountered
limitation in my line of work ;-)

regards
George

Oh No wrote:
Thus spake "John (Liberty) Bell"

2) I have yet to see an adequately satisfactory explanation of how that
proposed effect can produce a red shift on one side of a galaxy, and a
blue shift on the opposite side, whilst still giving the observed
Pioneer blue shift, on both sides of the Solar System.

What is measured is a shift in the wavefunction corresponding to an
eigenstate of acceleration.

What, precisely, do you mean by this?

For a general motion in radial coordinates a
Newtonian acceleration toward the origin is given by -r^dotdot + r w^2,
where r is radial distance and w is angular velocity.

Quite so, when we are dealing with Newtonian gravitational physics.
However, you have already said under previous discussions that
Newtonian physics remains unaltered in your theory (hence MOND
compatibility), and have indicated your effect is just due to your
predicted changes in frequency of the emitter relative to the observer,
which does not represent a real change in velocity or acceleration.

Are you now saying that your predicted effect is dependent on the
Newtonian state of motion of the emitter relative to the observer or
not? If so, how, precisely?

In the case of
Pioneer the motion is principally radial and the first term dominates;
the result is an illusory radial acceleration.

Fine, provided your predicted effect is _independent of_:
a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

For a star in orbit the
motion is approximately circular, so the second term dominates. The
actual calculation is a little more complicated, but the net result for
a star in orbit is an apparent increase in orbital velocity, or rather a
shift in the wave function equivalent to such an increase.

Not fine if you are claiming to explain galaxy rotation curves without
dark matter or modifications to Newtonian physics, unless your
predicted effect is _dependent on_:

a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

Requirements abc and ABC appear to be mutually contradictory.

John (Liberty) Bell
http://global.accelerators.co.uk
(Change John to Liberty to respond by email)

Thus spake "John (Liberty) Bell"

Oh No wrote:
Thus spake "John (Liberty) Bell"

2) I have yet to see an adequately satisfactory explanation of how that
proposed effect can produce a red shift on one side of a galaxy, and a
blue shift on the opposite side, whilst still giving the observed
Pioneer blue shift, on both sides of the Solar System.

What is measured is a shift in the wavefunction corresponding to an
eigenstate of acceleration.

What, precisely, do you mean by this?

In quantum theory a general state is not measured and it is not possible
to discuss values of measurable properties in such a state. When a
measurement is done the measured property acquires an exact value and
the state is said to be in an eigenstate for the corresponding
observable operator. Corresponding to any state there is a wave
function. In standard quantum theory in flat space the wavelength of the
wave function corresponds to momentum in inverse proportion. I am
suggesting that in curved space this proportionality is broken. That the
wavelength is shifted but the classical momentum of an orbiting body is
not altered.

For a general motion in radial coordinates a
Newtonian acceleration toward the origin is given by -r^dotdot + r w^2,
where r is radial distance and w is angular velocity.

Quite so, when we are dealing with Newtonian gravitational physics.
However, you have already said under previous discussions that
Newtonian physics remains unaltered in your theory (hence MOND
compatibility), and have indicated your effect is just due to your
predicted changes in frequency of the emitter relative to the observer,
which does not represent a real change in velocity or acceleration.

yes

Are you now saying that your predicted effect is dependent on the
Newtonian state of motion of the emitter relative to the observer or
not? If so, how, precisely?

If motion is, as for pioneer, essentially radial, acceleration
determined is determined by r^dotdot. In this case the effect appears as
a Doppler drift. For an orbital motion acceleration is r w^2. In this
case constant acceleration corresponds to a fixed Doppler shift.

In the case of
Pioneer the motion is principally radial and the first term dominates;
the result is an illusory radial acceleration.

Fine, provided your predicted effect is _independent of_:
a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

yes

For a star in orbit the
motion is approximately circular, so the second term dominates. The
actual calculation is a little more complicated, but the net result for
a star in orbit is an apparent increase in orbital velocity, or rather a
shift in the wave function equivalent to such an increase.

Not fine if you are claiming to explain galaxy rotation curves without
dark matter or modifications to Newtonian physics, unless your
predicted effect is _dependent on_:

a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

Requirements abc and ABC appear to be mutually contradictory.

Very briefly, to show how this works, and without going into gory
detail: At any time we actually measure velocity, not acceleration.
Inward acceleration for a body in a circular orbit is v^2/r. If the true
orbital velocity of a star in orbit about a mass M due to gravity is v_g
= sqrt(GM/r) and the apparent orbital velocity due to a constant inward
acceleration is v_P = sqrt(Hcr/32) (the factor 32 comes in because of a
weird stretching needed for quantum coordinates) then the net observed
apparent orbital velocity is

v = v_g + v_P

As you say, this satisfies requirements abc. But the apparent
acceleration is

v^2/r = (v_g + v_P)^2/r

= GM/r^2 + sqrt(GMHc/8)/r + Hc/32

The first term is standard Newtonian gravity, the second is the apparent
MONDian acceleration. The third is a term which comes from taking the
centre of the galaxy as the origin of coordinates, while actually we are
looking at light from a star. It is actually a mathematical artefact and
cannot be directly observed.





Regards

--
Charles Francis
substitute charles for NotI to email

Oh No writes:
Thus spake "John (Liberty) Bell"
Oh No wrote:
Thus spake "John (Liberty) Bell"

2) I have yet to see an adequately satisfactory explanation of how that
proposed effect can produce a red shift on one side of a galaxy, and a
blue shift on the opposite side, whilst still giving the observed
Pioneer blue shift, on both sides of the Solar System.

What is measured is a shift in the wavefunction corresponding to an
eigenstate of acceleration.

What, precisely, do you mean by this?

In quantum theory a general state is not measured and it is
not possible to discuss values of measurable properties
in such a state. When a measurement is done the measured property
acquires an exact value and the state is said to be in an eigenstate
for the corresponding observable operator. Corresponding to any state
there is a wave function. In standard quantum theory in flat space the
wavelength of the wave function corresponds to momentum in inverse
proportion. I am suggesting that in curved space this proportionality is
broken. That the wavelength is shifted but the classical momentum of an
orbiting body is not altered.

The obvious problem with your above claim is that, even if one assumes that
one _can_ construct a self-adjoint "acceleration operator," an "eigenstate
of acceleration" would almost certainly be unphysical and non-normalizable,
for the same reasons that eigenstates of position or momentum are unphysical
and non-normalizable.

In particular, one may expect that an "eigenstate of acceleration" would be
_completely delocalized_, much as an eigenstate of momentum is completely
delocalized --- leaving one with absolutely no information about position.

By contrast, in "Real World" measurements, one would only be able to observe
position, velocity, and acceleration to _finite precision_, and hence, even if
one believes that "wave function collapse" is a "physical process" rather
than an artifact of the observer's revised knowledge about the state of the
quantum system, the result of a finite precision "acceleration measurement"
will =NOT= in fact be an "eigenstate of acceleration," but rather an
incoherent _MIXTURE_ of eigenstates of acceleration, with an uncertainty
determined by the precision of the "acceleration measurement"...


-- Gordon D. Pusch

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

Thus spake "John (Liberty) Bell"

Oh No wrote:
Thus spake "John (Liberty) Bell"

2) I have yet to see an adequately satisfactory explanation of how that
proposed effect can produce a red shift on one side of a galaxy, and a
blue shift on the opposite side, whilst still giving the observed
Pioneer blue shift, on both sides of the Solar System.

What is measured is a shift in the wavefunction corresponding to an
eigenstate of acceleration.

What, precisely, do you mean by this?

In quantum theory a general state is not measured and it is not possible
to discuss values of measurable properties in such a state. When a
measurement is done the measured property acquires an exact value and
the state is said to be in an eigenstate for the corresponding
observable operator. Corresponding to any state there is a wave
function. In standard quantum theory in flat space the wavelength of the
wave function corresponds to momentum in inverse proportion. I am
suggesting that in curved space this proportionality is broken. That the
wavelength is shifted but the classical momentum of an orbiting body is
not altered.

For a general motion in radial coordinates a
Newtonian acceleration toward the origin is given by -r^dotdot + r w^2,
where r is radial distance and w is angular velocity.

Quite so, when we are dealing with Newtonian gravitational physics.
However, you have already said under previous discussions that
Newtonian physics remains unaltered in your theory (hence MOND
compatibility), and have indicated your effect is just due to your
predicted changes in frequency of the emitter relative to the observer,
which does not represent a real change in velocity or acceleration.

yes

Are you now saying that your predicted effect is dependent on the
Newtonian state of motion of the emitter relative to the observer or
not? If so, how, precisely?

If motion is, as for pioneer, essentially radial, acceleration
determined is determined by r^dotdot. In this case the effect appears as
a Doppler drift. For an orbital motion acceleration is r w^2. In this
case constant acceleration corresponds to a fixed Doppler shift.

In the case of
Pioneer the motion is principally radial and the first term dominates;
the result is an illusory radial acceleration.

Fine, provided your predicted effect is _independent of_:
a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

yes

For a star in orbit the
motion is approximately circular, so the second term dominates. The
actual calculation is a little more complicated, but the net result for
a star in orbit is an apparent increase in orbital velocity, or rather a
shift in the wave function equivalent to such an increase.

Not fine if you are claiming to explain galaxy rotation curves without
dark matter or modifications to Newtonian physics, unless your
predicted effect is _dependent on_:

a) distance from centre of gravity
b) radial velocity relative to observer
c) gravitational field

Requirements abc and ABC appear to be mutually contradictory.

Very briefly, to show how this works, and without going into gory
detail: At any time we actually measure velocity, not acceleration.
Inward acceleration for a body in a circular orbit is v^2/r. If the true
orbital velocity of a star in orbit about a mass M due to gravity is v_g
= sqrt(GM/r) and the apparent orbital velocity due to a constant inward
acceleration is v_P = sqrt(Hcr/32) (the factor 32 comes in because of a
weird stretching needed for quantum coordinates) then the net observed
apparent orbital velocity is

v = v_g + v_P

As you say, this satisfies requirements abc. But the apparent
acceleration is

v^2/r = (v_g + v_P)^2/r

= GM/r^2 + sqrt(GMHc/8)/r + Hc/32

The first term is standard Newtonian gravity, the second is the apparent
MONDian acceleration. The third is a term which comes from taking the
centre of the galaxy as the origin of coordinates, while actually we are
looking at light from a star. It is actually a mathematical artefact and
cannot be directly observed.





Regards

--
Charles Francis
substitute charles for NotI to email

Oh No wrote:

For an orbital motion acceleration is r w^2. In this
case constant acceleration corresponds to a fixed Doppler shift.

But this is clearly wrong! For a spiral galaxy viewed from above or
below, no such Doppler shift is observed (beyond second order
relativistic effects). For a spiral galaxy observed edge on, with its
nearest part moving from left to right, extremities on the left hand
side of the galaxy are observed to be blue shifted (far more than
predicted by Newtonian theory without dark matter), whilst extremities
on the right hand side of the galaxy are observed to be red shifted
(far more than predicted by Newtonian theory without dark matter).

For observers in different directions, the Doppler shifts of all the
stars change!

This is why your thesis doesn't make any sense.


John (Liberty) Bell
http://global.accelerators.co.uk
(Change John to Liberty to respond by email)

wrote:
John (Liberty) Bell wrote:
wrote:
.
The anomaly was observed for 20 years, thus giving an accumulated
round trip difference of ~ 400,000 km hence time difference of
1second.

The first report I have seen of the anomaly is gr-qc/9808081
and their last contact was in January 2003. If they had tried
your method as soon as the anomaly was seen as being
real and not just a flaw in the analysis, the best they could
get was less than 5 years and the last decent signal was
April 2002.

I refer you to section 2.1 of gr-qc/9903024 v2 which confirms that the
anomaly was first noticed in 1980. If my arithmetic is correct, this
makes 22 years elapsed from first observation to the last decent
signal, and 26 years to the present.

This makes the timing constraint somewhat more relaxed than you suggest
here. Furthermore, although an accurate figure for this distance
discrepancy would be ideal, it is only necessary to establish whether
there is any unambiguous distance discrepancy or not, within the
available timing uncertainties, in order to answer the question of
whether the apparent anomalous acceleration had real consequences or
not. This, I suggest, makes any total timing uncertainty of 1 second
adequate for answering that question.

They would need at least three readings (at best 2.5 years
apart) to separate a real acceleration from an error in the
initial vector

You are mistaken. There is no ambiguity over where or when Pioneer 10
was launched.
There is similarly no ambiguity over the Doppler figures monitored
thereafter.

John (Liberty) Bell
http://global.accelerators.co.uk
(Change John to Liberty to respond by email)

John (Liberty) Bell wrote:
wrote:
...
I refer you to section 2.1 of gr-qc/9903024 v2 which confirms that the
anomaly was first noticed in 1980.

I previously read this as saying that in 1987, they
identified the anomaly which showed an effect on
the craft from 1980 onwards. It would be reasonable
to take it your way as well.

If my arithmetic is correct, this
makes 22 years elapsed from first observation to the last decent
signal, and 26 years to the present.

If they had realised the measurement was needed
and had done it straight away in 1980 then yes
about 20 years might have been available. The SNR
in 2002 might not have allowed an accurate measure
but a year or two earlier should have provided an
adequate signal.

They would need at least three readings (at best 2.5 years
apart) to separate a real acceleration from an error in the
initial vector

You are mistaken. There is no ambiguity over where or when Pioneer 10
was launched.

Over 20 years the anomaly produces a displacement
of about 174000 km. An error in inital speed of just
0.276 m/s would produce the same displacement in
the same time.

There is similarly no ambiguity over the Doppler figures monitored
thereafter.

On the contrary, the usefulness of the range
measurements would be to distinguish whether
the frequency was shifted due to motion of the
craft via the Doppler effect or whether the
frequency was being directly affected in some
manner without matching displacement.

George

"John (Liberty) Bell" writes:
Craig Markwardt wrote:
....
The fact that such _off_ control was only used by NASA/JPL to provide
extra power for manoeuvres, does not restrict humanity to blindly
following that precise procedure in perpetuity. My point was that we
might potentially exploit our own intelligence and originality to
perform an experiment which was not part of the original Pioneer plan.

One of the top rules of spacecraft operations is: "don't turn anything
off unless you absolutely must." There is a finite chance that
whatever is turned off won't be recoverable. The communications
system is vitally important to the mission, so there is no reason to
ever turn it off.[*]
[*] ... except in the case when power is low and maneuvers must be
performed to preserve communications of course!

....
The traveling wave tube amplifier, the device that
is turned off and then on again after the maneuver, is a macroscopic
device with elements that must warm up and stabilize.

That is also irrelevant, if the proposed measured action is a switch
_off_, not switch on, as I suggested, originally to overcome the signal
lock time uncertainty.

Still, given the various elements inside of the device, it's likely
that it will not just "switch off" quickly. [ For example, if there
is an heated cathode electron gun in the amplifier, it will not be
possible to cool it instantly. ]

....
The spacecraft
and ground receiver have acquisition and tracking loops which are not
totally deterministic (and take at least several seconds to acquire).
Such a technique would also only produce one estimate of the light
travel time. Thus, your proposed technique is totally unreliable for
precision navigation.

You seem to have misunderstood the purpose of the proposal. It was not
to provide precise navigation. It was to establish whether the apparent
anomalous acceleration was demonstrably real, in the sense of resulting
in a different elapsed distance, or illusory, as suggested by Charles
Francis.

I think that is a distinction without a difference. Nobody would
believe one or two round trip travel times. To be believable and
robust, many ranges would be needed, and they would need to be placed
in context of a trajectory model. I.e. a full navigation solution
would be needed.

....

CM

wrote:
John (Liberty) Bell wrote:
wrote:
..
I refer you to section 2.1 of gr-qc/9903024 v2 which confirms that the
anomaly was first noticed in 1980.

I previously read this as saying that in 1987, they
identified the anomaly which showed an effect on
the craft from 1980 onwards. It would be reasonable
to take it your way as well.

If my arithmetic is correct, this
makes 22 years elapsed from first observation to the last decent
signal, and 26 years to the present.

If they had realised the measurement was needed
and had done it straight away in 1980 then yes
about 20 years might have been available. The SNR
in 2002 might not have allowed an accurate measure
but a year or two earlier should have provided an
adequate signal.

They would need at least three readings (at best 2.5 years
apart) to separate a real acceleration from an error in the
initial vector

You are mistaken. There is no ambiguity over where or when Pioneer 10
was launched.

Over 20 years the anomaly produces a displacement
of about 174000 km. An error in inital speed of just
0.276 m/s would produce the same displacement in
the same time.

There is similarly no ambiguity over the Doppler figures monitored
thereafter.

On the contrary, the usefulness of the range
measurements would be to distinguish whether
the frequency was shifted due to motion of the
craft via the Doppler effect or whether the
frequency was being directly affected in some
manner without matching displacement.

That was precisely my point in the first place. However, I still
maintain that a single direct ranging observation (the later the
better) would have sufficed (and still might suffice) to answer that
question.

As I understand it, the basic principle of ranging using Doppler data
is as follows:
Measuring the Doppler shift gives an accurate figure of the radial
velocity of the probe relative to the observer, at any given time.
Integrating that data over time gives an accurate figure for the total
radial distance travelled by the probe relative to that observer.
Looked at another way, the total difference between the number of
signal oscillations since launch, and the total number that would have
been observed in the same time if the probe remained on Earth, provides
a direct (Doppler) measure of the total radial distance travelled by
the probe, in that time.

Yes, we can jiggle our model of the exact trajectory somewhat to
modify both tangential relativistic corrections to Doppler shifts and
the predicted decelerations of our model due to gravity. However, the
reported anomaly is the _minimum_ anomaly that remains after all such
adjustments are taken into account, given e.g. the tight constraints
provided by observations performed during planetary catapaulting.

Such data indicates
a) that the probe has travelled less far than predicted
b) that the probe is travelling slower than predicted
c) that the probe is continuing to decelerate faster than predicted.

Consequently, all we need to do to test if the conclusions reached by
Doppler observations are physically meaningful is to test if the total
distance travelled is greater than the distance admitted by Doppler
ranging. The _minimum_ additional distance required for a round trip
signal (if Doppler conclusions are illusory) would already have been
greater than 1 light second (using your own figure for 1980 to the last
good signal), and would have been even larger if that Pioneer Doppler
effect was present (but unrecognised) prior to 1980. It is thus
completely irrelevant when the effect was first noticed, for the
purpose of testing that hypothesis.

John Bell
http://global.accelerators.co.uk
(Change John to Liberty to respond by email)