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New research

Should this be added to the page?
Exotic cause of 'Pioneer anomaly' in doubt
I'd do it, but I can't be bothered to absorb the entire page well enough to put this in the right place. :)
Aristotle 11:48, 22 June 2007 (UTC)

This used to be on the page, though in a paper by Iorio rather than the paper referenced in the article (though they have exactly the same conclusion). I checked and it was removed by an anonymous editor 63.130.192.57 on 25 May, while also removing some more dubious stuff. I've re-added it to the possibility of gravitational causes. LouScheffer 15:33, 22 June 2007 (UTC)

New Horizons

According to Alan Stern, prime investigator of New Horizons space probe (former Pluto-Kuiper Express), this probe will be spin-stabilized during cruise and thus his radio team is hoping to look for the Pioneer Anomaly in their data. -- Mandevil 09:15, 24 Feb 2005 (UTC)

Interesting. Do you have a reference for this? I couldn't find any coverage.
Dr. Stern's info is in this thread in New Horizons forum on MER forum; it is a reply to my direct question about this matter.-- Mandevil 16:37, 8 Mar 2005 (UTC)
That's brilliant, thanks. I've mentioned it. -- JTN 21:10, 2005 Mar 8 (UTC)
The last reference in Pioneer anomaly states:
In addition, many of the deep-space missions that are currently being planned either will not provide the needed navigational accuracy and trajectory stability of under 10−8 cm c−2 (i.e. Pluto Express) [...]
but then it is drumming up support for a dedicated mission, and also they refer to "Pluto Express" which seems a bit outdated.
-- JTN 13:00, 2005 Feb 24 (UTC)

' As far as i have heard, the radiation pressure from the rtg should mask the 'anomaly' for new horizons. nevertheless, people might try to use the REX instrument (which is basically a radio transmission expreriment as a "probe") and to compute precisely the thermal radiation pressure.

a recent reference for that : New Horizons and the Onset of the Pioneer Anomaly, Michael Martin Nieto http://arxiv.org/abs/0710.5135v1

OK, added this to the article. -- LouScheffer (talk) 21:16, 16 November 2007 (UTC)

Are all already known effects accounted for?

I just wonder have the scientists accounted for Sol gravitational well when estimating the drift? What i mean is that electromagnetic wave increase/decrease in frequency when escaping/incoming the gravity center

one more thing to be careful about is the speed of the pioneer - how big the relativistic effects are at that speed (time dilation) - have this effect been accounted for?

one more question - "The drift can be interpreted as due to a constant acceleration of (8.74 ± 1.33) × 10−10 m/s2 directed towards the Sun." could this be caused by the masses of all the planets and asteroids in the solar system (especialy the Jupiter) ?


Regarding your questions: yes, the gravitational Doppler effect has been accounted for in the calculations, and introduces a negligible correction which cannot explain the anomaly. This is a standard procedure in telemetry and Doppler analysis of any spacecraft.

Also, the crafts are travelling at a speed that is many order of magnitudes lower than the speed of light, so that time dilation cannot account for the effect. Furthermore, since the effect reveals itself through the unexplained Doppler shift, the relevant relativistic correction is the aforementioned gravitational Doppler effect.

Finally: although the numbers don't match, it could be possible that, at a certain time and position throughtout its voyage, the probes were subject to a gravitational pull from Jupiter and other bodies that equals the anomaly. However, the key word here is "constant acceleration": all gravitational forces decrease with the inverse of the distance squared, so it appears impossible to describe a constant effect through it. And, of course, all known gravitational effects were previously accounted: NASA engineers do mean business (Anderson et. al.)!

A slightly more convoluted discussion involves the gravitational force due to objects in the Kuiper belt. It has been shown (Bertolami and Vieira) that only a exceedingly odd density profile for these objects could approximate the effect, and even so only within a narrow region of space.

Hope I was of some help.

Jorge

The source of the constant acceleration could simply be due to the earth's rotation. The uncertainty with which the latter is known corresponds practically exactly to the observed discrepancy (see my page http://www.physicsmyths.org.uk/pioneer.htm for more).
Thomas

Thomas your page has one additional piece of information, that the beam of the antenna is not wide enough to deduce anything but a earth directed acceleration, if that is true the story is possibly a hoax , as it tends to digress to sun-pointing accelleration instead. Anyway i can imagine gravitational drags or magnetic shifts of some influence, I would also not be surprised if it was the shadow of the antenna. perhaps the relevance of the earth magnetic field naturally gets more pronounced on certain trajectorys but i would think that had very limited windows.(1g per au is suggestive) I don't know in how far metal molds correspond to the overall earth magnetic field(not to bad i think) and i can't imagine it would matter this much(the flyby effect seems the effect of earth magnetic (gravitational) variation but i dont know if that could induce that variety, i would think yes since the effect is small and the earth is big, perhaps eg. it matters if the part you fly over is warm).77.248.56.242 23:34, 13 June 2007 (UTC)

Possible explainations

The wrong sign? Please explain

"The pressure of sunlight is too small at this distance, and the wrong sign, as are the spacecraft's radio emissions"

You mean, "and is on the wrong side"?? --129.139.18.18 18:54, 9 April 2007 (UTC)

Not really, see the very first post above. The "sign" of the force created by the radio emissions, for instance, would be the wrong one, it would accelerate the craft ourward, not inward. Maury 21:18, 18 April 2007 (UTC)

Zoran Ozimec ?

I removed today (April, 18, 2007) the likely self-promoting external link to [1], compilation of JPEG files of non-peer-reviewed scanned manuscripted work (see the historic to see when and how it had been added, November 2006). Nevertheless, I have no clue in physics, so it would be useful that anyone a bit more aware than I am have a look at his page and see if the link needs be added once more.

People have been doing Eotvos experiments with non-similar masses for a very long time now, pretty much right from the start, in order to test this concept. They've even done it with anti-matter because some supersymmety threories suggested antimatter would fall slower. In every peer-reviewed case I have heard of, the equivalence principle remained perfect to measurable capabilities. That page has a link to several such experiments, with modern ones that are to parts in the trillions. The P10 effect is parts per ten billion. These experiments directly contradict this guy's claim, over 30 years ago. Maury 21:16, 18 April 2007 (UTC)

The Many Directions of Time

Someone took issue with my addition of a link to Alexander Mayer's The Many Directions of Time, so I thought I'd expand on it a little here. First, I have absolutely no connection with Mayer other than having read his work. Yes, it is a self-published ebook. However, the transverse gravitational redshift theory is firmly grounded in general relativity and makes many empirically testable predictions. This is the hallmark of a good scientific hypothesis. If this was obvious quackery such as Time Cube removing it would be justified, but that's not the case here. Whether Mayer is right or wrong, removing a reference to a possible explanation because you don't like the web page is, in my opinion, a disservice to Wikipedia readers.

I took a look at this, and don't think it belongs in an encyclopedia article. As far as I can see it has at least 6 strikes against it. (1) On the very first page, it says "This book is going to change the course of scientific history. Many old ideas (and inflated reputations) will pass away." This is a VERY BAD SIGN. If your theory is really that good, you don't need to assert it, and the reputations will take care of themselves.(2) The document claims not only to solve the Pioneer anomaly, but reverse many other long-standing physics ideas. For example, all conventional redshift interpretations are wrong. "The 1929 [conventional] interpretation of cosmological redshift is certainly incorrect and therefore all the WMAP team's confident conclusions outlined below actually have no bearing on empirical reality". Also general relativity - "The common obsequious drivel about the "beauty" of Einstein's equations is ironic to say the least. In fact, his theory incorporated a momentous error that created an artificially convoluted monstrous tangle of tensor equations that do not accurately reflect physical reality", Einstein's equivalence principle is not correct, and so on. (3) Explaining away inconvenient experimental results: His theory predicts the atomic clocks in Paris will see the American clock go more slowly, *and* vice versa (the Americans will see that the French clocks are going slow. ). But this is not observed, so he claims that for political reasons (his italics) everyone ignores this and just sets their clocks to the global average to avoid controversy. (As a personal note, has he ever met any of these folks?? These are folks to whom an unexplained variation in the 16th decimal place is cause for panic. These are the *last* people in the world to simply ignore an error and calmly set their clock to a politically acceptable value.) (4) The document quotes great swaths of other publications, and goes to great pains to say why this is needed for an accurate discussion of other's ideas. But his document itself is locked against any selection of text. I had to type in the above quotes above.
And this is not just me - (5) It has never been published in any scientific literature I could find, including arXiv. And arXiv standards are pretty loose, at most you need one endorsement from some existing author. And this is plenty to get people to take your ideas seriously. Craig Markwardt's "Independent Confirmation of the Pioneer 10 Anomalous Acceleration" has never been published anywhere else, but has 26 cites. (6) It is never referred to anywhere I can find in any scientific literature (google scholar, arxiv, citeseer), either as "the many directions of time" or "traverse gravitational redshift".
So I think this should go. Any other votes??

I'll try to address each of your points.

  1. Yes, Mayer has a habit of making bold and/or arrogant statements. This may be unfortunate, but it has little bearing on the science.
  2. Yes, the theories are radical. So were relativity, quantum theory and the big bang. You seem to have one error here though - Mayer does not claim that the equivalence principle is wrong. In fact it's part of the basis of the TGR hypothesis and Mayer states "Einstein's Equivalence Principle is one of the most powerful ideas in the history of science and one of the simplest."
  3. I do not understand your comments on the atomic clocks at all. Mayer makes the claim as you say, and then proceeds to produce data and graphs that support the claim - he's not explaining away anything. In one paragraph he mentions that this experiment should be fairly easy to do, given the falling cost of highly accurate clocks. I believe that he hopes that someone will do the experiment.
  4. Yes, the PDF is digitally signed and protected against selection. I believe this is simply an attempt to maintain control over hardcopy publishing of the book, since he is selling the printed version.
  5. I'm afraid I can't say much about Mayer's choice of publishing method.
  6. This material is quite new - it didn't emerge in any form until late last year and the book is only a few months old. I don't find it surprising that it hasn't been cited anywhere.

In summary, I have no idea if Mayer is right. He may well be wrong. But I find his claims and supporting data compelling enough to warrant some investigation. Given the plethora of empirically testable predictions made in the book, some enterprising experimentalists ought to be able to discover whether or not Mayer is on to something - but for that to happen, they have to at least be aware of the theories, hence my motivation for making the information available. The list we are editing is called "Possible explanations", not "Ironclad explanations" and all of the new physics portion involves controversial modifications to current theories. I don't see why Mayer is any different in that regard. I'll say one thing - he seems to be doing a heck of a lot better than the superstring theorists at making testable predictions.

I think his theories fail some common sense tests. For example, we both agree that he thinks that the clocks in the USA and Paris should each perceive each other as running more slowly. Let's see what this implies.
  • First set up fiber optic lines between the clocks. They will transmit ticks to each other, each at a rate determined by their own clock. They merely observe the other's clock, and do not control it. Pick the tick rate such that at most one tick is in transit between the clocks at any time, as seen by either clock.
  • Now have the USA clock count the ticks until it has ticked 3 more times than Paris. This will eventually happen since the USA perceives the Paris clock to be slower. Call the USA clock count at this point N. At this time the Paris clock has ticked at most N-2 times, since at most 1 tick can be in transit. Now switch to the Paris clock, and consider when it has ticked N-2 times. At this time it has seen N-5 ticks from the American clock. (since it perceives the American clock as going slower, and the effect is symmetrical). So the American clock has emitted at most N-4 ticks, since only one can be in transit.
  • So the theory predicts than when the USA clock has ticked N times, we can also show it has ticked at most N-4 times. This is a contradiction.
This is a very specific example of a much more general case. Two clocks, ticking at rate R, separated by a bounded time T, cannot each see the other ticking at rate uniformly lower than themselves. Eventually the difference will exceed T *in both directions*, and a contradiction is assured. You might as well seek two functions, each smaller than the other by a uniform multiplier. LouScheffer 05:34, 28 June 2007 (UTC)

The case you are talking about (two clocks each perceived as running more slowly than the other) is extremely common within Einsteinian special relativity - that's how relativistic time dilation works. If one observer is moving at high speed relative to another and each are transmitting clock data, they will perceive each other's clocks as being slower than theirs. Do you also assert that special relativity is wrong? I think the problem with your scenario is that you are making the assumption that there really is a consistent universal time axis that you can measure against, which is just not the case for Mayer's geometric time or for relativistic time dilation. It defies common sense, but each observer really will have different tick counts because the perceived frequencies of each clock is not the same. In fact, if you read Mayer's work you find that the whole concept of geometric time is rooted within special relativity, much as TGR is rooted in general relativity. Pheran 15:39, 28 June 2007 (UTC)

No, the reason these cases work in special relativity is that they only happen when there is relative motion, and the limit of the speed of light. The number of ticks in transit varies, and always adds/subtracts to the clock differences, at least so that all events that happen in the same place happen in the same order to all observers, independent of their frame of reference.
This is not true in the proposed theory. Take a satellite equally spaced between the US and Paris atomic clocks. It emits a flash of light and each group starts their clock when they see it. After 1 year (each as measured by their own clocks) each group emits a flash of light. Which does the satellite see first? The USA group will say the USA flash will be seen first, since they see the Paris clock as running slower. The Paris group will expect the Paris flash first. But only one of these two results is possible. Any theory that makes two different predictions of the order of events *at the same place* is inconsistent. (And if the result is a tie, then each group must conclude the other clock is running at the same rate.)
At some larger level, you don't need me to be a skeptic - there are plenty of skeptics. What you need are people (preferably people with a track record in physics) who believe in this theory, or at least that it *might* be right.
Finally, this theory is much larger than the Pioneer anomaly. Putting a reference here is like putting a reference to atomic energy on a page on night-lights. It's certainly true that atomic energy might make a longer lasting night-light, but that's not its main importance. Likewise, if the cosmological interpretation of redshift is wrong, or general relativity is wrong, that's a much bigger deal than explaining the Pioneer anomaly. If anywhere it should go on these pages.

1. Effect, 1.1 Possible explanations: effects in the gravitational field

Dear editors, the data provided below was added earlier into the article, in the related section, but then removed with the comment "ESA ref does not mention pioneer, second ref is another self-published TOE by a non-scientist". Well, although the ESA link, 2006, does not mention the pioneer anomaly it does demonstrate the possible deviations from Einstein-Newtonian law of gravitation that Kunst's paper already in 1999 refers as being measured in laboratory and at astronomical scale; the second ref as you may very well deduce, and as it is known by several "relativity" editors around, it is a 2002 paper from a scientist with a highly reputable background, yet a taboo among the academic physics community (ask yourselves why!):

« The research into the apparent deviations from the Einstein-Newtonian law of gravitation, both on laboratory and astronomical scale,(1) suggest that the phenomena (the Pioneer 10/11 gravitation anomaly) is due to the gravitational effects of the mass of the gravitational field, the mass of the field-vacuum (2); a similar conclusion was also reached by an elderly aether theorist, suggesting that the phenomena is due to an effect attributable to retarded energy deployment in the gravitational field.(3)
References
(1) ESA News, Towards a new test of general relativity, March 2006
(2) Kunst, Ernst Karl. Do Gravitational Fields Have Mass? (arXiv:physics/9911007v1 [physics.gen-ph])
(3) Aspden, Harold (MInstP). A New Insight into the Pioneer 10/11 Gravitation anomaly »

Obviously, from my past editing experiences here at Wikipedia there seems to be many individuals around not interested that the lay public becomes acquainted with these other perspectives within the scientific community. Friendly. —The preceding unsigned comment was added by 213.58.99.92 (talkcontribs) 23:17, 23 July 2007 (UTC).

Yes, choosing to interpret the removal "unsupported self-published" material as unfriendly is certainly easy. Unfortunately it doesn't change the fact that it's unsupported self-published material, which is clearly against wikipedia guidelines. You're perfectly free to make your own site and publish as you see fit, which is what I assume is what the site in question is. Further, the ESA report has nothing to do with the topic at hand, and we have only your word that it is in any way related. The only useful link was the arxiv one, and its link to the ESA is likewise unmentioned. There have been many other theories of gravity, scalar-tensor for instance, but their existence, by itself, is meaningless. Maury 00:39, 24 July 2007 (UTC)

In line with WP:BOLD, I am removing a pile of external links that I think are better not in the article. If someone, after double checking relevant wikipedia guidelines, feels that some of these should be restored, do please feel free to revert individual links as you see fit. If this occurs, I will not revert back. I may tag the link, and engage discussion here.

Here are links I have removed.

Re: No current PhD, or any other scholastic grade, is able to offer you even the shadow of the knowledge that this elderly author (see the backgound) has uncovered in a whole life devoted to pursuit Truth, not the instituted dogma nor its proud and vain honorific titles and prizes. And you label it as "dubious credibility"!? You should at least consider to do what the rest of the his peers appear to have been doing already for a while: to be silent and learn (read a book) about how the future paradigm of Science, not the current materialist-reducionist science, will look like. Hope it helps; A layman.

These are the links that remain.

Duae Quartunciae (talk · cont) 22:17, 29 July 2007 (UTC)

Consider this (a non-broken version of the Yahoo link) for re-inclusion, although I think much of it is already covered. Maury 21:31, 30 July 2007 (UTC)

Is this really significant?

Maybe I did the math wrong, but a force of (8.74 ± 1.33) × 10^−10 m/s2 across 35 years (1.10449241 × 10^9 seconds) works out to just a few meters. We don't even know the exact location of GPS satellites orbiting Earth within a few meters. So I would imagine that it's well within the range of measuring error for the Pioneer spacecraft. —Preceding unsigned comment added by 69.244.30.43 (talk) 18:37, 14 October 2007 (UTC)

Sorry, but your math *is* wrong. The change in *speed* = a*t is about 1 m/sec, relatively easy to measure with doppler shift, which is orders of magnitude more sensitive. The change in distance is quite big: s = 1/2 a t^2. Assuming for simplicity 10^-9 m/s^2 and t=10^9, the distance differs by 5x10^8 meters, or about 500,000 km. So the measurement is quite secure. —Preceding unsigned comment added by LouScheffer (talkcontribs) 18:50, 14 October 2007 (UTC)