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![]() Craig Markwardt wrote: "GSS" writes: Craig Markwardt wrote: "GSS" writes: ... DNu_mod/Nu_0 = 2 v_mod/c ..... (4) And 2 v_obs/c = DNu_obs/Nu_0 ..... (5) ... It has been mentioned in the above quoted reference that *all relativistic corrections* have been incorporated in the model. In this regard kindly give your opinion whether it is possible that the so called relativistic corrections themselves could be the source of the Anomalous effect?? No. Switching from relativistic to classical physics only worsens the solution, not improves. Has this been tried out? If so by whom and what is the quantitative difference in the Anomalous effect? Yes, by me. Changing from relativistic to classical Doppler shifts essentially adds noise to the solution, which is of order a few Hz. This is appropriate since the difference between the two kinds of Doppler shifts occurs at second order in (v/c). It's also understandable since the dominant Doppler shifts are the earth's motion and rotation (factor of 2-3 times larger than the spacecraft speed w.r.t. the sun). The anomaly itself is still present with both methods, just noisier with classical Doppler shifts. From the above quoted reference [arXiv:gr-qc/0104064 v5] it appears that the Relativity corrections have been used both for improving accuracy of the model and to use such an improved model for testing the Relativity Theories. Quoting from pages 12 and 14 of this reference - "Responding to the increasing demand of the navigational accuracy, the gravitational field in the solar system is modeled to include a number of relativistic effects that are predicted by the different metric theories of gravity. Thus, within the accuracy of modern experimental techniques, the parameterized post-Newtonian (PPN) approximation of modern theories of gravity provides a useful starting point not only for testing these predictions, but also for describing the motion of selfgravitating bodies and test particles." "Indeed, this dynamical model has been good enough to perform tests of general relativity." Or, from the above quoted reference [arxiv.org/gr-qc/0208046], "The equations of motion I used [... included ... ] aN ... due to Newtonian gravity" and "[Anderson et al 2002] considers additional terms for the acceleration which allow for alternate theories of gravity (their equation 3). I find that over the span of the data, these terms are always smaller than 3x10^{-12} cm/s^2 and thus I neglect them for the purposes of Doppler tracking analysis. So, despite using Newtonian gravity, the anomaly was the same. Adding the relativistic terms to the equation of motion did not change the solution appreciably. Thanks for the clarification. Doesn't it appear to be fundamentally illogical to first use Relativity to perfect the model and then to use that model to test Relativity. If the Relativity does need to be tested then why use it till its clearance through authentic testing? Ignoring for the moment that your question is moot -- given the above description -- the first "P" in the PPN theory of gravity is "parameterized." The PPN theory is parameterized family of gravity models, *not* just GR. And is it also possible that some theoretical error in the Doppler relations (4) and (5) could lead to the observed Anomalous effect? Relations 4 and 5 are inexact representations of the Doppler shift. The exact relativistic formulation improves the solution. Craig Kindly provide the ' exact relativistic formulation ' in place of relations (4) and (5) or atleast provide a reference for the same. Kindly consult the referred-to papers, for example, gr-qc/0208046 eq 2. CM Let me try to reproduce equation 2 from your paper gr-qc/0208046 since I intend to have a detailed discussion on this issue. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ˆr12 · v2/c^2)/(1 - ˆr12 · v1/c^2)] ............. (2) The unit vector ˆr12 points from the transmitting station to the spacecraft, i.e., ˆr12 = r12/r12. This equation appears to be wrong since it is not dimensionally balanced. Perhaps it should have been as given below. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ˆr12 · v2/c)/(1 - ˆr12 · v1/c)] ............. (2') Kindly confirm. GSS |
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![]() "GSS" writes: Craig Markwardt wrote: "GSS" writes: Craig Markwardt wrote: "GSS" writes: ... DNu_mod/Nu_0 = 2 v_mod/c ..... (4) And 2 v_obs/c = DNu_obs/Nu_0 ..... (5) ... It has been mentioned in the above quoted reference that *all relativistic corrections* have been incorporated in the model. In this regard kindly give your opinion whether it is possible that the so called relativistic corrections themselves could be the source of the Anomalous effect?? No. Switching from relativistic to classical physics only worsens the solution, not improves. Has this been tried out? If so by whom and what is the quantitative difference in the Anomalous effect? Yes, by me. Changing from relativistic to classical Doppler shifts essentially adds noise to the solution, which is of order a few Hz. This is appropriate since the difference between the two kinds of Doppler shifts occurs at second order in (v/c). It's also understandable since the dominant Doppler shifts are the earth's motion and rotation (factor of 2-3 times larger than the spacecraft speed w.r.t. the sun). The anomaly itself is still present with both methods, just noisier with classical Doppler shifts. From the above quoted reference [arXiv:gr-qc/0104064 v5] it appears that the Relativity corrections have been used both for improving accuracy of the model and to use such an improved model for testing the Relativity Theories. Quoting from pages 12 and 14 of this reference - "Responding to the increasing demand of the navigational accuracy, the gravitational field in the solar system is modeled to include a number of relativistic effects that are predicted by the different metric theories of gravity. Thus, within the accuracy of modern experimental techniques, the parameterized post-Newtonian (PPN) approximation of modern theories of gravity provides a useful starting point not only for testing these predictions, but also for describing the motion of selfgravitating bodies and test particles." "Indeed, this dynamical model has been good enough to perform tests of general relativity." Or, from the above quoted reference [arxiv.org/gr-qc/0208046], "The equations of motion I used [... included ... ] aN ... due to Newtonian gravity" and "[Anderson et al 2002] considers additional terms for the acceleration which allow for alternate theories of gravity (their equation 3). I find that over the span of the data, these terms are always smaller than 3x10^{-12} cm/s^2 and thus I neglect them for the purposes of Doppler tracking analysis. So, despite using Newtonian gravity, the anomaly was the same. Adding the relativistic terms to the equation of motion did not change the solution appreciably. Thanks for the clarification. Doesn't it appear to be fundamentally illogical to first use Relativity to perfect the model and then to use that model to test Relativity. If the Relativity does need to be tested then why use it till its clearance through authentic testing? Ignoring for the moment that your question is moot -- given the above description -- the first "P" in the PPN theory of gravity is "parameterized." The PPN theory is parameterized family of gravity models, *not* just GR. And is it also possible that some theoretical error in the Doppler relations (4) and (5) could lead to the observed Anomalous effect? Relations 4 and 5 are inexact representations of the Doppler shift. The exact relativistic formulation improves the solution. Craig Kindly provide the ' exact relativistic formulation ' in place of relations (4) and (5) or atleast provide a reference for the same. Kindly consult the referred-to papers, for example, gr-qc/0208046 eq 2. CM Let me try to reproduce equation 2 from your paper gr-qc/0208046 since I intend to have a detailed discussion on this issue. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ˆr12 · v2/c^2)/(1 - ˆr12 · v1/c^2)] ............. (2) The unit vector ˆr12 points from the transmitting station to the spacecraft, i.e., ˆr12 = r12/r12. A typo. This equation appears to be wrong since it is not dimensionally balanced. Perhaps it should have been as given below. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ˆr12 · v2/c)/(1 - ˆr12 · v1/c)] ............. (2') Kindly confirm. Confirmed. CM |
#83
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![]() John C. Polasek writes: On 27 Jun 2006 10:46:22 -0500, Craig Markwardt wrote: John C. Polasek writes: ... You must know that I am talking about all real, maser-verfiied clocks that accelerate compared to the artificial clock in the model which for several reasons must have a constant value. The result is the ramp function on the chart. ... For the nth time, there is no "artificial clock" in the model. The station clock at the time of the tracking session is used in the model. If you continue with your fiction, I can only assume that you are not interested in substantiated debate. CM I may be misinterpreting what is in the model, but what I have tried to represent in the upper model leg is a digital differential analyzer doing numerical integration on data taken from the ephemeris and double integrating it for range that would then update the ephemeris. In so doing only the constant G is involved, and it's all mathematical. Then to produce anything resembling frequency, for later comparison with the real hardware, from the point V(t), one must introduce the multiplier -f0/c. In this regard I would expect that the multiplier is a mathematic constant being 1/WL. If this is wrong, just say so and I can modify my model, but then tell me how this coefficient -f0/c is brought up to date with the transmitting clock. With an analog computer, yes, or using the station clock to drive the DDA, but that looks like a nullity also. It is clear there is substantial misunderstanding somewhere. Yes, you have a problem. Why don't you start to fix it by reading the referred-to papers, or George or my previous posts, which you seem to be conveniently ignoring? CM |
#84
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![]() Craig Markwardt wrote: John C. Polasek writes: On 27 Jun 2006 10:46:22 -0500, Craig Markwardt wrote: John C. Polasek writes: ... You must know that I am talking about all real, maser-verfiied clocks that accelerate compared to the artificial clock in the model which for several reasons must have a constant value. The result is the ramp function on the chart. ... For the nth time, there is no "artificial clock" in the model. The station clock at the time of the tracking session is used in the model. If you continue with your fiction, I can only assume that you are not interested in substantiated debate. CM I may be misinterpreting what is in the model, but what I have tried to represent in the upper model leg is a digital differential analyzer doing numerical integration on data taken from the ephemeris and double integrating it for range that would then update the ephemeris. In so doing only the constant G is involved, and it's all mathematical. Then to produce anything resembling frequency, for later comparison with the real hardware, from the point V(t), one must introduce the multiplier -f0/c. In this regard I would expect that the multiplier is a mathematic constant being 1/WL. If this is wrong, just say so and I can modify my model, but then tell me how this coefficient -f0/c is brought up to date with the transmitting clock. With an analog computer, yes, or using the station clock to drive the DDA, but that looks like a nullity also. It is clear there is substantial misunderstanding somewhere. Yes, you have a problem. Why don't you start to fix it by reading the referred-to papers, or George or my previous posts, which you seem to be conveniently ignoring? CM Dear Craig Markwardt, please, look at: http://groups.google.com/group/sci.p...e=source&hl=en My arguments and interpretation of anomaly of "Pioneers" can change your approach to interpretation of the problem. |
#85
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On 29 Jun 2006 02:05:58 -0500, Craig Markwardt
wrote: John C. Polasek writes: On 27 Jun 2006 10:46:22 -0500, Craig Markwardt wrote: John C. Polasek writes: ... You must know that I am talking about all real, maser-verfiied clocks that accelerate compared to the artificial clock in the model which for several reasons must have a constant value. The result is the ramp function on the chart. ... CM I may be misinterpreting what is in the model, but what I have tried to represent in the upper model leg is a digital differential analyzer doing numerical integration on data taken from the ephemeris and double integrating it for range that would then update the ephemeris. In so doing only the constant G is involved, and it's all mathematical. Then to produce anything resembling frequency, for later comparison with the real hardware, from the point V(t), one must introduce the multiplier -f0/c. In this regard I would expect that the multiplier is a mathematic constant being 1/WL. If this is wrong, just say so and I can modify my model, but then tell me how this coefficient -f0/c is brought up to date with the transmitting clock. With an analog computer, yes, or using the station clock to drive the DDA, but that looks like a nullity also. It is clear there is substantial misunderstanding somewhere. Yes, you have a problem. Why don't you start to fix it by reading the referred-to papers, or George or my previous posts, which you seem to be conveniently ignoring? I see where I muddied the waters by talking about -f0/c. I should have said f0: The model is totally artificial, a mathematical construct, and it requires 3 prescribed numerical coefficients G, -f0/c and finally f0. The important one is f0 which I say retains a constant prescribed value, while the real clocks run away from it by Hubble acceleration. (The part depending on -f0/c is as I have said, a negligible contributor.) The additive f0 in my flowgraph has to be a constant with the same value today as it had 20 years ago, or show me how, and why, it has been altered. You say "the station clock at the time of the tracking session is used in the model". Please tell veryspecifically how this can be done. (We are looking for nothing more nor less than a new NUMERICAL value of f0 to go into the model). (As can be seen from the graph a new offset to f0 would simply offset the graph). To be facetious, (or realistic) what would cause the technician, who has just turned on the station clock, to call up the computer room and announce a new number for f0? Checking the frequency with NIST would be simplest. You can update an atomic clock over the telephone. Their site has a sample daily record of a clock being checked, that shows infinitesimal *random* daily changes about +-2e-13 which is nothing. Remember that by hypothesis, NIST's masers have advanced by exactly the same fraction as the statioin clock, so they all march together. But f0 in the model is stuck in the past. Tell me how the number f0 is custom adjusted to the station clock's frequency, when there is no way of determining its frequency in the first place. My argument is simply that f0 is set in stone, and by hypothesis, all atomic real clocks are secularly advancing, leading to the 1.5/8 discrepancy. It simply accounts for the anomaly. CM John Polasek http://www.dualspace.net |
#86
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![]() Craig Markwardt wrote: "GSS" writes: Craig Markwardt wrote: "GSS" writes: ...... So, despite using Newtonian gravity, the anomaly was the same. Adding the relativistic terms to the equation of motion did not change the solution appreciably. Thanks for the clarification. ...... Let me try to reproduce equation 2 from your paper gr-qc/0208046 since I intend to have a detailed discussion on this issue. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ^r12 · v2/c^2)/(1 - ^r12 · v1/c^2)] ............. (2) The unit vector ^r12 points from the transmitting station to the spacecraft, i.e., ^r12 = r12/r12. A typo. This equation appears to be wrong since it is not dimensionally balanced. Perhaps it should have been as given below. d_12 = {sqrt[1 - |v1|^2/c^2]/sqrt[1 - |v2|^2/c^2]} . [(1 - ^r12 · v2/c)/(1 - ^r12 · v1/c)] ............. (2') Kindly confirm. Confirmed. CM Again quoting from page 4 of your paper, "The epoch of transmission from the Earth is t1, the epoch of interaction of the signal with the Pioneer 10 spacecraft is t2, and the epoch of reception back at the Earth is t3. All of these times are referred to the Barycentric Dynamical Timescale (TDB), which is a coordinate time at the solar system barycenter. TDB is also the effective argument of the JPL planetary ephemerides. The 3-vectors r1, r2, and r3 represent the positions of the corresponding antenna at the corresponding epoch, and v1, v2, and v3 represent the velocities. *The vector difference, r12, is defined as r1 - r2.* These vector quantities are measured in the solar system barycenter frame." Perhaps the vector difference, r12, should have been defined as r2 - r1. Further, ----------------- "The final term in equation 1, DNu_path, represents additional Doppler effects caused by small effective path length changes, aside from those due to geometric antenna motions. Generally speaking, this term can be written as, DNu_path = -2 dl/dt.Nu_0/c, where dl/dt is the time rate of change of effective photon trajectory path length along the line of sight. The factor of 2 comes from the two legs of the round trip path. In this paper I consider the effective path length due to the "Shapiro" delay. The Shapiro delay reflects the extra proper distance traveled by a photon, beyond the classical geometric distance, in the Sun's gravitational potential, as predicted by general relativity," " l_shap = 2.(GM/c^2).ln[(r1+r2+r12)/(r1+r2-r12)] ..... (3)" "On an annual timescale, the impact parameter of the photon trajectory increases and decreases, with a minimum distance of about 8×106 km. Conversion to a Doppler shift is achieved by numerically differentiating equation (3), which yields an annual signal with amplitude ±150 mHz." ---------------------- During the period of your analysis (1987-1994), r2r1. Therefore, apart from a cyclic term given by annual variation of r1 in equation (3), we get a dominant, steadily varying term dependent on steadily increasing r2 as, l_shap = 2.(GM/c^2).ln[r2/r1] ..... (4) This yields (approximately), DNu_path/Nu_0 = -4(GM/c^2).(1/r2).(v2/c) .... (5) This is the term which is expected to make a significant contribution to the Doppler residuals apart from a cyclic term dependent on annual variation of r1. Can you kindly give some quantitative figures for this contribution to the Doppler residuals during the period of your analysis? GSS |
#87
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![]() "Aleksandr Timofeev" writes: Craig Markwardt wrote: John C. Polasek writes: On 27 Jun 2006 10:46:22 -0500, Craig Markwardt wrote: John C. Polasek writes: ... You must know that I am talking about all real, maser-verfiied clocks that accelerate compared to the artificial clock in the model which for several reasons must have a constant value. The result is the ramp function on the chart. ... For the nth time, there is no "artificial clock" in the model. The station clock at the time of the tracking session is used in the model. If you continue with your fiction, I can only assume that you are not interested in substantiated debate. CM I may be misinterpreting what is in the model, but what I have tried to represent in the upper model leg is a digital differential analyzer doing numerical integration on data taken from the ephemeris and double integrating it for range that would then update the ephemeris. In so doing only the constant G is involved, and it's all mathematical. Then to produce anything resembling frequency, for later comparison with the real hardware, from the point V(t), one must introduce the multiplier -f0/c. In this regard I would expect that the multiplier is a mathematic constant being 1/WL. If this is wrong, just say so and I can modify my model, but then tell me how this coefficient -f0/c is brought up to date with the transmitting clock. With an analog computer, yes, or using the station clock to drive the DDA, but that looks like a nullity also. It is clear there is substantial misunderstanding somewhere. Yes, you have a problem. Why don't you start to fix it by reading the referred-to papers, or George or my previous posts, which you seem to be conveniently ignoring? CM Dear Craig Markwardt, please, look at: http://groups.google.com/group/sci.p...e=source&hl=en My arguments and interpretation of anomaly of "Pioneers" can change your approach to interpretation of the problem. The principle of equivalence has been tested quite narrow tolerances in the solar system already (Williams et al 1996), so your supposition will probably not be fruitful. CM References Williams, Newhall & Dickey 1996, Phys Rev D, 53, 6730 |
#88
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![]() "GSS" writes: " l_shap = 2.(GM/c^2).ln[(r1+r2+r12)/(r1+r2-r12)] ..... (3)" "On an annual timescale, the impact parameter of the photon trajectory increases and decreases, with a minimum distance of about 8×106 km. Conversion to a Doppler shift is achieved by numerically differentiating equation (3), which yields an annual signal with amplitude ±150 mHz." ---------------------- During the period of your analysis (1987-1994), r2r1. Therefore, apart from a cyclic term given by annual variation of r1 in equation (3), we get a dominant, steadily varying term dependent on steadily increasing r2 as, l_shap = 2.(GM/c^2).ln[r2/r1] ..... (4) This yields (approximately), DNu_path/Nu_0 = -4(GM/c^2).(1/r2).(v2/c) .... (5) This is the term which is expected to make a significant contribution to the Doppler residuals apart from a cyclic term dependent on annual variation of r1. Can you kindly give some quantitative figures for this contribution to the Doppler residuals during the period of your analysis? You are welcome to estimate it yourself, but they are negligible. The "Shapiro effect" is very strongly detected; one can't simply ignore some terms and accept other terms as you have done. CM |
#89
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![]() "Joe Jakarta" writes: Craig Markwardt wrote: [...] The principle of equivalence has been tested quite narrow tolerances in the solar system already (Williams et al 1996), so your supposition will probably not be fruitful. I wonder how the anomalous Pioneer blue-drift compares for size with GR one due to the Sun's gravity? Do you mean the difference gravitational redshift between the earth and the spacecraft? Since the spacecraft re-transmits the uplink signal on the downlink channel, including the same frequency and phase, any redshift of the signal on the uplink leg is cancelled by an equal blueshift on the downlink leg. CM -- -------------------------------------------------------------------------- Craig B. Markwardt, Ph.D. EMAIL: Astrophysics, IDL, Finance, Derivatives | Remove "net" for better response -------------------------------------------------------------------------- |
#90
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![]() John C. Polasek writes: I see where I muddied the waters by talking about -f0/c. I should have said f0: The model is totally artificial, a mathematical construct, and it requires 3 prescribed numerical coefficients G, -f0/c and finally f0. The important one is f0 which I say retains a constant prescribed value, while the real clocks run away from it by Hubble acceleration. (The part depending on -f0/c is as I have said, a negligible contributor.) The additive f0 in my flowgraph has to be a constant with the same value today as it had 20 years ago, or show me how, and why, it has been altered. Your model description is not reflective of reality, therefore it is irrelevant. You say "the station clock at the time of the tracking session is used in the model". Please tell veryspecifically how this can be done. It's easy. The transmission frequency was *recorded* at that time, thus it is available to be used in the model. ... (We are looking for nothing more nor less than a new NUMERICAL value of f0 to go into the model). There is no f0. Every tracking session contains its own record of the frequency used *at that time*. Those frequencies are used in the model. THERE IS NO "F0" FROM 1987 STORED IN THE MODEL. When will you get this? ...(As can be seen from the graph a new offset to f0 would simply offset the graph). To be facetious, (or realistic) what would cause the technician, who has just turned on the station clock, to call up the computer room and announce a new number for f0? Actually, the uplink frequency for a given session is crudely adjusted so that when the signal arrives at the spacecraft, it will be within the spacecraft receiver's bandpass. So the uplink frequency for each tracking session is customized to the conditions. .... My argument is simply that f0 is set in stone, and by hypothesis, all atomic real clocks are secularly advancing, leading to the 1.5/8 discrepancy. It simply accounts for the anomaly. Since your argument is erroneous, your conclusions are irrelevant. CM |
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