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Alternative theories being tested by Gravity probe B |
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| Jan8-07, 10:24 AM | #35 |
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Alternative theories being tested by Gravity probe B
Thank you Frederic henryco and welcome to these Forums! Join the club of those waiting for the GP-B results!
Has your Dark Gravity theory been published in a recognised peer reviewed journal? If so we could discuss it in a separate thread, if not you may want to submit it to the Independent Research Forum for discussion, but read the "Rules for submission" first! We now have a line up of eight theories competing in the Gravity Probe B stakes, which are: Einstein's General Relativity(GR) Barber's Self Creation Cosmology (SCC), Moffat's Nonsymmetric Gravitational Theory (NGT), Hai-Long Zhao's Mass Variance SR Theory (MVSR), Stanley Robertson's Newtonian Gravity Theory (NG), and Junhao & Xiang's Flat Space-Time Theory (FST). R. L. Collin's Mass-Metric Relativity (MMR) and F. Henry-Couannier's Dark Gravity Theory (DG). The predictions are: 1. GPB Geodetic precession (North-South) GR = 6.6144 arcsec/yr SCC = 4.4096 arcsec/yr NGT = 6.6144 - a small [itex]\sigma[/itex] correction arcsec/yr MVSR = 6.6144 arcsec/yr NG = 1.6536 arcsec/yr FST = 4.4096 arcsec/yr MMR = -6.56124 arcsec/yr DG = 6.6144 arcsec/yr 2. GPB gravitomagnetic frame dragging precession (East-West) GR = 0.0409 arcsec/yr SCC = 0.0409 arcsec/yr NGT = 0.0409 arcsec/yr MVSR = 0.0102 arcsec/yr NG = 0.0102 arcsec/yr FST = 0.0000 arcsec/yr MMR = -0.01924 arcsec/yr DG = 0.0000 arcsec/yr There is the question of whether these alternative theories pass all the other tests of GR as detailed in Clifford Will's paper The Confrontation between General Relativity and Experiment. Three months to go, whatever those results may be! Garth |
| Jan31-07, 12:06 AM | #36 |
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Hi Garth – New here to the forum but saw your posts and thought I would mention a potential discovery resulting from the GP-B experiment. Please add it to your list.
No, I do not have an alternative gravity theory but I do question the current model of precession and I believe GP-B (with its perfect gyros far above the wobbling earth) is in an ideal position to determine if the precession of the equinox observable (a change in earth orientation of about 50”p/y) is due to the torque of lunisolar forces acting on the oblate earth (current theory) or the observable of a solar system in motion (binary theory of precession). If I guess right, the spacecraft will mimic the precession observable even though it is floating free high above a wobbling earth. This is because we believe the precession observable is due to the motion of the sun and solar system curving through space. I met with the GP-B team at Stanford a few months ago and they listened and were open minded about the possibility that our sun may have an unknown companion star (which is the theoretical cause of the solar system curving through space at 50”p/y). We discussed the polhode issue and they implied they were getting more signals than originally anticipated and it was a big task to try and separate all of the signals into identifiable buckets. But they were careful to keep the integrity of the experiment and remind me that they could not release results until the public announcement. Nonetheless, we spent a fair amount of time discussing companion star scenarios, which I found interesting. Bottomline, I think they will either report that it will take more time than expected to sift and interpret all the signals, and or, that our solar system is curving through space at a rate that exceeds the expected results from the relativity experiment. I have posted a model (of the results I expect them to find) on my website at the Binary Research Institute: http://www.binaryresearchinstitute.o...avprobeb.shtml Regardless of the results of the initial GP-B report I think NASA and Stanford are providing almost priceless research. The raw data should prove to be fundamentally helpful to scientists for years to come as we probe the motions of the earth and solar system on our journey through space. Bravo to Dr. Everitt and team! |
| Jan31-07, 01:00 AM | #37 |
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Polestar 101, I loved your website. What I would like to see is more detailed explanation of why the usual calculations are incorrect.
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| Jan31-07, 01:27 AM | #38 |
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Carl - Your point is well taken. While I do not have any good theory as to why the current model fails we do have pretty good observable evidence that the earth hardly wobbles at all relative to local objects within the solar system. In other words, our best calculations are that we see about 4"p/y of precession relative to the Moon, Venus and the Persieds (which we are using as local markers) while at the same time we can observe a full 50"p/y of re-orientation relative to the fixed stars and quasars far outside the SS. This tells me there must be a logical explanation to allow the two simultaneous observables but we have not focused on flaws with the current local dynamics model - as of yet.
One simple guess is the Moon tugs on the earth and this is responsible for the nutation observable (the 18 year Saros cycle signature reflects the known motions of the Moon). But the much longer precessional cycle (which is slowly speeding up) does not reflect any known motion of the Moon. Perhaps the unaccounted for dynamic is the SS motion through space (possibly offsetting the tendency towards local precession). Anyway, there are a lot of issues. We hope to address some of them in a new paper once we have access to the GPB public data. Until then...you take a crack at it, and if it stands the test of time, I will nominate you for the Galileo Award. Walter |
| Jan31-07, 01:58 AM | #39 |
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Polestar welcome to these Forums and welcome to this thread!
What I do not understand about your theory is the 26,000 year precession has been well known since the Ancient Greeks and caused by the Moon & Sun's attraction on the Earth's equatorial bulge, causing a well understood gyroscopic motion. This is a precession of ~50"/yr. I cannot believe that the analysis by Newcombe at end of the 19th Century and then Lieske with satellite technology in the 1970's is all totally erroneous. Are you saying that there is another precession of ~ 50"/yr that has not been modelled? In which case why has it not already been observed by stellar observations? If the Sun and its retinue were in orbit with a companion star with period 25,800 years the companion star would have been discovered by now. In the 1980's I did some work on 'Nemesis', the possible cause of perturbations of the Oort cloud and a possible ~32Myr periodicity of mass extinctions on Earth. That would have had an orbital period of ~32Myr (SMA ~ 105 AU), and the conclusion was it should have already been seen either optically or in the IRAS data (if a brown dwarf). I notice on your website that you link to several of your papers, but I do not find any references to them being published in peer reviewed journals. In which case such discussion is not appropriate here. You may wish to submit your ideas to the Independent Research Forum after first reading their submission rules. Garth |
| Jan31-07, 03:24 PM | #40 |
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Hi Garth – It is not really my theory as others have mentioned it for years. And you’re right the precession of the equinox has been observed for thousands of years, and yes, that is the ~50”p/y observable we are discussing.
It has long been assumed to be the result of strictly local forces acting upon the oblate earth producing a gyroscopic motion. Traditionally, it has been measured (by VLBI and others) relative to very distant reference points (stars or quasars far outside the SS) because distant points obviously move less than local points. However, in recent studies of the motion of the equinox relative to objects within the SS it turns out the earth wobbles very little compared to local points of reference (like the Moon). At BRI we have been working to better understand this seeming paradox: an earth that wobbles ~ 4”p/y relative to objects “inside the SS”, while at the same time showing ~ 50”p/y relative to objects “outside the SS”. One possibility is that part of the total observable, that we have attributed to local forces, might actually be due to the geometric effect of the SS's angular motion through space. This of course brings up the question of what it could be moving around, and hence several astronomers are examining companion star scenarios. As you aptly noted, one of those is a brown dwarf concept, like Nemesis, but there are other Newtonian scenarios that run from blackholes to unknown planet like masses, as well as non-Newtonian scenarios such as MOND, that would raise the far out possibility that it could even be a nearby visible star. Please understand I am not advocating any particular solution on this board, I am just trying to obtain more data at this time to better understand the precession observable. Can hardly wait until the GPB data is released - so please keep us posted! Walter |
| Jan31-07, 05:35 PM | #41 |
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Walter, what prediction of the East-West and North-South precessions does this theory make?
I still find it difficult to believe that a substantial object with SMA ~ 877 AU would not have already been discovered. And yes I agree that Francis Everitt and team are doing a marvellous job and roll on April 14th! Garth |
| Feb2-07, 12:04 AM | #42 |
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Garth - No prediction as I do not believe SS motion would affect the GR part of the experiment. It is my understanding that just as the GPB team has to remove the effect of the motion of the spacecraft around the earth (~5"), and remove the effect of the motion of the earth around the sun (~20"), so too would they need to remove any signal from the motion of the solar system curving through local space as all of these affect the abberation of light relative to the guidestar. For a graphic see:
http://www.binaryresearchinstitute.o...avprobeb.shtml Your calculation sounds about right for a brown dwarf scenario. And I agree it is doubtful that we would not have seen that type of object by now. Consequetly, if SS motion is confirmed in the ~ 50"p/y range, as the precession data leads me to believe, and we do not find anything in the 500-1000AU range, we need to condsider more exotic scenarios. Mid April is probably optomistic. My guess is that due to the sheer volume of data (including possible unexpected signals) and the need to better understand and crunch that data, the GPB team will likely need more time. With an experiment this profound we should probably expect the unexpected. Walter |
| Feb10-07, 01:51 AM | #43 |
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Latest news on the publication of GP-B results:
I knew it! ![]() The April APS meeting: Garth |
| Feb10-07, 02:06 AM | #44 |
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And it is to be hoped that we won't find 50 years from now that "the reduction of the margin of error" was done with the same kind of "enthusiasm" as Eddington did in 1919. |
| Feb10-07, 02:35 AM | #45 |
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Well that prediction did't take long to come true! Here is another: At least one of their unexpected signals (that they have to seperate out) is magnitudes larger than the GR effects they are looking for.
Walter |
| Feb10-07, 07:25 AM | #46 |
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However I take their statement above: Garth |
| Feb12-07, 07:05 AM | #47 |
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I have just read your email (i had forgotten to check this extra email box all these days). Your idea looks very interesting also from the point of view of the expectations in the framework of my dark gravity theory. Indeed, in this theory i assumed my preferred frame to be the sun frame and then i got an anomalous angle deviation related to the motion of earth (and GP-B) around the sun. But if the preferred frame is defined by a larger group of stars, then the effect should be much larger and may be, as you say, related to the equinoxe precession. All this is very exciting. I will try to attend the april meeting where the first announcement of GP-B results is expected. Unfortunately i cannot access the URL you give. I'm also convinced that the GP-B results will be a major breakthrough in our understanding of gravity. Could you please let me know why i'm not able to access your website...may be its secured isn't it. best regards F Henry-couannier |
| Feb15-07, 02:02 PM | #48 |
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Garth |
| Feb15-07, 05:45 PM | #49 |
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Just as GPB will pick up the 5"+ per orbit signal as an aberration of light between the spacecraft and the guidestar, and just as they pick up the 20"+ p/y signal due to the earth's orbit around the sun, so too should they pick up a nearly 50"p/y signal if we are correct the precession observable is mainly the geometric effect of a solar system in motion. My concern is what that signal looks like in the data. The spacecrafts orbital motion has a waveform in synch with the spacecrafts orbit periodicity, which will show many waves during the experiment period, so this known signal will be easy to spot. The orbit of the earth around the sun should also be clear since it is a known motion and the experiment period allows time for both an ascending and descending phase. However, the binary motion (if it exists) would only reveal about 1/26,000ths of its waveform during the experiment period. Since it is completely unexpected, and no one is looking for it, it might just be attributed to anomalous drift or assumed to be part of the pollhode motion?? I just don'y know. Fortunately, the controls on this experiment are so tight and the people involved so professional I am encouraged they will take all precautions to carefully identify every signal before announcing the final GR results. Time will tell. Walter Cruttenden |
| Feb16-07, 06:01 PM | #50 |
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Well Walter, as I said, I find it hard to believe that:
1. The Moon does not induce the observed 26,000 yr period precession on the Earth as all the models of the geoid predict and, 2. There is an unobserved ~ stellar mass object, which is a binary companion to the Sun with a SMA of ~ 877AU that is responsible for the said observed precession. On the other hand the Abstract for Francis Everitt's paper to be given at the APS Jacksonville conference in April reads. Einstein's General Relativity(GR) Barber's Self Creation Cosmology (SCC), Moffat's Nonsymmetric Gravitational Theory (NGT), Hai-Long Zhao's Mass Variance SR Theory (MVSR), Stanley Robertson's Newtonian Gravity Theory (NG), Junhao & Xiang's Flat Space-Time Theory (FST). R. L. Collin's Mass-Metric Relativity (MMR) and F. Henry-Couannier's Dark Gravity Theory (DG). The predictions are: 1. GPB Geodetic precession (North-South) GR = 6.6144 arcsec/yr SCC = 4.4096 arcsec/yr NGT = 6.6144 - a small [itex]\sigma[/itex] correction arcsec/yr MVSR = 6.6144 arcsec/yr NG = 1.6536 arcsec/yr FST = 4.4096 arcsec/yr MMR = -6.56124 arcsec/yr DG = 6.6144 arcsec/yr 2. GPB gravitomagnetic frame dragging precession (East-West) GR = 0.0409 arcsec/yr SCC = 0.0409 arcsec/yr NGT = 0.0409 arcsec/yr MVSR = 0.0102 arcsec/yr NG = 0.0102 arcsec/yr FST = 0.0000 arcsec/yr MMR = -0.01924 arcsec/yr DG = 0.0000 arcsec/yr But first, as I said, these alternative theories have to also pass all the other tests of GR as detailed in Clifford Will's paper The Confrontation between General Relativity and Experiment. Garth |
| Feb21-07, 10:19 PM | #51 |
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Please also notice that DG predicts a small preferred frame effect to be seen by GP-B. It's a one year periodicity angular deviation with amplitude 0.005 arcsec...at the limit of GP-B sensitivity but i hope still detectable...and i thinck this is the "subtle effect " they need 10 more months to understand. PLease have a look at gr-qc/0702028 the latest paper by Turyshev, Nordtvedt and co regarding gravitomagnetism and Lunar Laser Ranging. It says something incredible! It says that the frame-dragging is seen in the frame of the observer (earth frame) where there should be nothing at all since in this frame the speed of the earth vanishes...but they keep using there (badly incorrect) the gravitomagnetic field formula of the sun rest frame. Crazy isn't it? PLease check this and tell me if i'm wrong!Best regards Fred |
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