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From: Surfer on 22 Feb 2010 02:26
On Sun, 21 Feb 2010 22:34:19 -0600, Tom Roberts
<tjroberts137(a)sbcglobal.net> wrote:

>
>There are TWO essential aspects to doing science: developing a theory, and then
>TESTING it experimentally. You need to do part 2 before you have anything of use.
>
Thanks for your feed back. The main concern of my post was to justify
the formula on theoretical grounds. That seems a necessary first step
before considering experimental tests.

>
>Other people, of course, know this. And the assumptions you used have been known
>for well over a century. Other people have developed theories based on those
>assumptions, but unlike you they have TESTED them. In all cases to date, such
>theories have failed the experimental tests.
>
Well here is a test. The spacecraft earth flyby anomalies have been
bothering the space agencies for some years. NASA even re-employed
John D. Anderson to try to find a solution. But as this recent paper
shows, it has still not been possible to find a solution using
mainstream physics.

Earth Flyby Anomalies
Michael Martin Nieto, John D. Anderson
Physics Today {\bf 62} (No. 10 Oct.), 76-77 (2009)
http://arxiv.org/abs/0910.1321

"In a reference frame fixed to the solar system's center of
mass, a satellite's energy will change as it is deflected by a planet.
But a number of satellites flying by Earth have also experienced
energy changes in the Earth-centered frame -- and that's a mystery"

However, during an earth flyby, space craft speed (and hence energy)
is determined using radar Doppler shift. This suggests the
possibility that the anomalies could be an illusion caused by use of
an inaccurate radar Doppler shift formula.

So a way to test the formula that I presented, would be to use it to
calculate the anomaly in spacecraft speed that would be observed, if
the new formula was correct but the standard formula was applied.

That has been done.

The figures below for observed anomaly in speed are taken from,
Anomalous Orbital-Energy Changes Observed during Spacecraft Flybys of
Earth
JD. Anderson et. al.
PRL 100, 091102 (2008)
http://virgo.lal.in2p3.fr/NPAC/relativite_fichiers/anderson_2.pdf

The predicted values are taken from.

Resolving Spacecraft Earth-Flyby Anomalies with Measured Light Speed
Anisotropy
RT Cahill
Prog. Phys.3:9-15,2008
http://www.ptep-online.com/index_files/2008/PP-14-02.PDF

Observed Predicted
3.92+/-0.3 3.92+/-0.1
-4.6 +/-1.0 -4.60+/-0.6
13.46+/-0.01 13.40+/-0.1
-2+/1 -0.99+/-1.0
1.80+/-0.03 1.77+/-0.3
0.02+/-0.01 0.025+/-0.03

The agreement is very good.

>You may think your theory is somehow "special". But given the actual history of
>physics, it is highly unlikely to survive experimental tests. So don't expect
>anyone else to care, until and unless you come up with a test that your theory
>passes and SR does not.
>
> Merely having an experimental record equal to that of SR is
> insufficient, as LET demonstrates. Your theory, of course,
> cannot be equal to SR (it makes some different predictions).
> That's another reason to be skeptical of your theory, as SR
> is completely unrefuted within its domain of applicability.
>

>
>> If one assumes the speed of light is isotropic in the frame of the
>> radar system, [...]
>
>That is, of course, an EXCELLENT assumption, because it has been OBSERVED for
>every locally-inertial frame an earthbound laboratory ever occupies.
>
But that can be confirmed with certainty only for the two way speed of
light.

Laboratory tests don't allow us to determine the one way speed of
light, because clocks are synchronized on the assumption that the one
way speed is equal to c. Laboratory tests using clocks will therefore
always show that the one way speed is c, irrespective of whether that
is actually the case.

So if we can't be sure of the true one way speed of light, then it is
probably inappropriate to apply SR to situations where results depend
on knowledge of the one way speed.

That appears to be the case with the Doppler radar formula.

That doesn't mean that the formulae of SR are wrong, only that they
may need to be more carefully applied.

-- Surfer




From: PD on 22 Feb 2010 15:33
On Feb 20, 9:08 pm, Surfer <n...(a)spam.net> wrote:
> The formula for radar Doppler shift can be derived without invoking
> Einsteins' theory of special relativity, because all observations are
> made in the same frame of reference.
>
> The result with c as the speed of light, V as the target velocity and
> Ft as the transmitted frequency, gives the shifted frequency Fr as:
>
>         Fr = Ft  (c+V)/(c-V)                                         (1)
>
> However I will show below that this formula would be inaccurate if the
> one way speed of light were to be isotropic only with respect to a
> preferred frame and justify an alternative formula.
>
> Suppose a frame of reference is identified in which the one way speed
> of light is 'truely' isotropic, referred to below as the 'isotropic
> frame'.  

Filippas and Fox showed experimentally that this is not the case.

>
> Suppose that relative to such a frame a radar system is moving with
> speed vi in the direction of a target, and that the target is moving
> towards the radar system with speed V relative to the radar system.
> (So vi, V and radar signals are collinear.)
>
>    ------------                                           ------------
>   | Radar   | ----------------c-vi------------>|Target |  
>   | System |<---------------c+vi------------ |           |
>   -------------                   signal               -----------
>     ---vi-->                      speeds             <--V--  
>    Radar system              relative            Target speed
>    speed  relative            to radar            relative to
>    to isotropic                 system             radar system
>    frame                                    
>
> To ensure consistent representation of distance and time, let time in
> the radar system frame be synchronized with time in the isotropic
> frame and let distance measurements be derived from the spatial
> coordinates of the isotropic frame. These conditions require the
> frames to be mapped to each other via Galilean transforms.
>
> Then in the frame of the radar system the transmitted signal will have
> a speed of
>           c-vi
>
> and the reflected signal will have a speed of
>           c+vi.
>
> Notes:
>   1) It would be usual to synchronize clocks in the frame of the
>       radar system such that signal speeds in this frame APPEAR
>       to be c in both directions.  This would be consistent
>       with mapping the frames to each other via Lorentz transforms.
>       But doing so here would cause representation of signal
>       propagation timing in the radar system frame to differ from
>       that in the isotropic frame. That would prevent derivation of
>       correct results.
>
>   2) The above speeds will give a calculated two way speed in
>        the frame of the radar system of c (1 - vi^2/c^2) using
>        the measures of length and time of the isotropic frame.
>        This would convert to a value of c if converted to the measures
>        of length and time that would apply in the radar system frame,
>        if the mapping was via Lorentz transforms. So the way the
>        Galilean transform is being used here does not conflict with
>        observed constancy of the two way speed of light in inertial
>        frames.
>
> In the radar system frame of reference, let the transmitted signal
> have frequency Ft, then the corresponding outgoing wavelength is,
>           Lt = (c - vi)/Ft    
>
> This signal will impinge on the target with period
>           T = Lt/(c - vi + V)
> or frequency
>           F = (c - vi +V )/Lt.
>
> The reflected signal has the same frequency, and so has wavelength
>           Lr = (c + vi - V)/F,
>
> and is received by the radar system with frequency
>           Fr = (c + vi)/Lr.
>
> Then overall we obtain,
>
>                         (c + vi)        (c - vi + V)
>           Fr =    ---------------    ----------------    Ft .                (2)
>                      (c + vi - V)        ( c - vi)      
>
> This formula was derived using the measures of length and time of the
> isotropic frame, but since changing the measures at this point would
> change the denominators and numerators in equal proportion,  such a
> change would not affect the ratio of Fr to Ft.
>
> So the formula can also be validly used with the measures that would
> normally apply in the radar system frame, that is, if the mapping
> between it and the isotropic frame had been performed with Lorentz
> transforms.
>
> When vi is zero the formula reduces to,
>
>            Fr = (c+ V)/(c - V) Ft
>
> which is equivalent to the standard formula (1) above.
>
> But if the one way speed of light is truely isotropic only wrt to a
> preferred frame, then in general vi will not be zero and the standard
> formula will give inaccurate results.
>
> -- Surfer

From: Surfer on 22 Feb 2010 20:55
On Mon, 22 Feb 2010 11:25:29 -0800 (PST), "Dono." <sa_ge(a)comcast.net>
wrote:

>On Feb 20, 7:08�pm, Surfer <n...(a)spam.net> wrote:
>> The formula for radar Doppler shift can be derived without invoking
>> Einsteins' theory of special relativity, because all observations are
>> made in the same frame of reference.
>>
>> The result with c as the speed of light, V as the target velocity and
>> Ft as the transmitted frequency, gives the shifted frequency Fr as:
>>
>> � � � � Fr = Ft �(c+V)/(c-V) � � � � � � � � � � � � � � � � � � � � (1)
>
>I showed you that deriving this formula is a simple exercise in SR.
>The above formula is confirmed by experiment.
>

I don't believe experiments performed so far have been accurate enough
to detect a difference.




From: Surfer on 22 Feb 2010 21:55
On Mon, 22 Feb 2010 12:33:02 -0800 (PST), PD
<thedraperfamily(a)gmail.com> wrote:

>On Feb 20, 9:08�pm, Surfer <n...(a)spam.net> wrote:
>> Suppose a frame of reference is identified in which the one way speed
>> of light is 'truely' isotropic, referred to below as the 'isotropic
>> frame'. �
>
>Filippas and Fox showed experimentally that this is not the case.
>
I found.

Velocity of Gamma Rays from a Moving Source
T. A. Filippas and J. G. Fox
Phys. Rev. 135, B1071�B1075
http://prola.aps.org/abstract/PR/v135/i4B/pB1071_1

That tested the idea that photons might travel at speed c relative to
the source from which they are emitted.

But what I wrote above is quite different.



From: eric gisse on 22 Feb 2010 23:02
Surfer wrote:

> On Mon, 22 Feb 2010 11:25:29 -0800 (PST), "Dono." <sa_ge(a)comcast.net>
> wrote:
>
>>On Feb 20, 7:08 pm, Surfer <n...(a)spam.net> wrote:
>>> The formula for radar Doppler shift can be derived without invoking
>>> Einsteins' theory of special relativity, because all observations are
>>> made in the same frame of reference.
>>>
>>> The result with c as the speed of light, V as the target velocity and
>>> Ft as the transmitted frequency, gives the shifted frequency Fr as:
>>>
>>> Fr = Ft (c+V)/(c-V) (1)
>>
>>I showed you that deriving this formula is a simple exercise in SR.
>>The above formula is confirmed by experiment.
>>
>
> I don't believe experiments performed so far have been accurate enough
> to detect a difference.

Is that belief based on the results of an actual literature search? Or a
guess?
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