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The Pioneer Anomaly & Other Breaking Physics News

David Harris, editor-in-chief at Symmetrymagazine.org (a joint publication of Fermilab and SLAC), sends us to his blog covering the American Physical Society meeting now going on in St. Louis. Among the breaking physics news relating to topics we have discussed in the past: results that explain about 1/3 of the Pioneer anomaly by differential heat flow in the spacecraft; an analysis of the Fermilab Tevatron's chances of spotting the Higgs "God particle"; and a hint that an Italian team has replicated their results from the year 2000 pointing to a detection of dark matter.

35 of 100 comments (clear)

  1. Sloppy editing by Harmonious+Botch · · Score: 4, Insightful

    We have three separate subjects crammed together in one article. So some of the briliant, insightful comments by my fellow shashdotters may get buried. How about three separate articles?
    Or is this a new trend? Are we going to see twenty subjects crammed into the one daily article tommorow?

    1. Re:Sloppy editing by Anonymous Coward · · Score: 4, Funny

      So some of the briliant, insightful comments by my fellow shashdotters may get buried.

      On the other hand, we may get somebody posting a fantastic Theory of Everything that shows that the other two-thirds of the reason why Pioneer is off-course is because it is being bombarded with Higgs particles while bumping into dark matter.

      But yes, I suppose that your prediction of stupid comments is also possible. It's 50/50 really.

    2. Re:Sloppy editing by An+ominous+Cow+art · · Score: 3, Funny

      Electric universe is stupid singularity evil. 4 Day Time Cube disproves 1 Day Electric Universe.

      Electric Universe is as evil as God singularity evil.

      I have $10,000.000 that I will wager that Cubicism transcends and disproves Electric Universism.

    3. Re:Sloppy editing by traveller.ct · · Score: 2, Funny

      IIRC, the answer to the Theory of Everything is 42, no?

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  2. You must be new here. by Valdrax · · Score: 4, Insightful

    So some of the briliant, insightful comments by my fellow shashdotters may get buried. When's the last time you've read the comments section on any science article on Slashdot, particularly over discoveries in physics?

    Insightful comments are *always* buried under senseless meme-tossing and political (or other off-topic) ranting.
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    1. Re:You must be new here. by Anonymous Coward · · Score: 2, Funny

      buried under senseless meme-tossing

      In soviet russia, memes toss you!

    2. Re:You must be new here. by PopeRatzo · · Score: 3, Insightful

      When's the last time you've read the comments section on any science article on Slashdot, particularly over discoveries in physics?
      Quite regularly thank you.

      I happen to believe Slashdot, even with minuscule expense of a subscription, is an excellent bargain.

      Except for the time I waste on whiners like you, Valdrax. As pointed out by McGiraf, do you really think you're going to improve the senseless meme-tossing by doing your own senseless meme-tossing?
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  3. Before LHC though? by stevedcc · · Score: 3, Interesting

    The article states that Fermilab can begin exploring to 160GeV in the summer. LHC is due to be switched on before that. From all I've read, LHC has a MUCH better chance of being sure of what it finds at around those energies. I think any article on this subject can't even pretend to be balanced without discussing LHC.

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    1. Re:Before LHC though? by yomegaman · · Score: 5, Informative

      The LHC will probably switch on this year, but it won't generate very much luminosity at first. Perhaps by the end of 2009 it will have made a couple of inverse femtobarns which would be enough, but it will be another year or so after that before the data are processed and analyzed. It takes quite a bit of time to understand and interpret the detector readout. The Tevatron does have a chance if the Higgs is around 160 GeV, but only with about one-in-a-thousand level statistical significance, and so far we are not seeing any excess of events there, but in fact somewhat fewer events than expected.

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      ...wearing a skin-tight topless leather jumpsuit, with cutaway buttocks and transparent crotch panel.
    2. Re:Before LHC though? by bockelboy · · Score: 4, Informative

      It's going to be a race, really, to see what happens first - the Tevatron squeaking out enough events to confirm detection, or the LHC operating smoothly enough to get all the calibration and background processes established, then finding the Higgs.

      It's going to be a close race. On one hand, the LHC will ramp up to have a huge advantage over the Tevatron. On the other hand, the Tevatron folks are at the top of their game.

  4. Re:Rumor/conjector by FooAtWFU · · Score: 3, Informative

    I read the article on Higgs, and it is entirely conjecture based on specified rumor after rumor. Is this TMZ.com? It's a summary of a physics conference. This is news of physicists describing to each other the state of the art and what they're busy conjecturing, considering, and hoping to prove. Perhaps you were looking for Nature?
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  5. Re:Rumor/conjector by yomegaman · · Score: 4, Informative

    The bump in the CDF two-tau decay channel went away with more data, which wasn't too surprising. I'm not sure how all that got so blown up in the science press, the original blog post that started it at Cosmic Variance surely didn't make any discovery claim. Having said that, the other half of the story, the rumored huge excess in the D0 three-b-quark channel, is still unresolved as they have not released any results for over a year. We'll probably see something within a few weeks I guess, I have heard that it is close to ready.

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  6. Re:Rumor/conjector by evil+agent · · Score: 4, Funny

    I know right? And what about that sensationalist headline: "Breaking Physics News"??? If they had actually broken physics, I probably would have heard it on the news...

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  7. On the Pioneer anomaly by Anonymous Coward · · Score: 5, Informative

    I read a discussion somewhere that many spacecraft pick up a sizable electric charge and keep it (they are after all in a vacuum), and that electrostatic forces from the Sun and the solar wind are enough to account for course deviations. It's certainly true that gravity is not the only force operating out there.

    1. Re:On the Pioneer anomaly by barath_s · · Score: 5, Informative

      Right, radiation pressure, gas leaks, drag, electric charge are all suspects, as are changes in the way data was collected. http://en.wikipedia.org/wiki/Pioneer_anomaly The issue is that the current best guesses for these effects do not yet account for the anomaly.

  8. Enough of the "God Particle" please by smolloy · · Score: 4, Insightful
    Who first used the name "The God Particle" for the Higgs? It certainly wasn't a high energy physicist!

    The Higgs field is supposedly responsible for mass generation -- and that's it. Nothing else. Maybe something about "spontaneous symmetry breaking...mumble... big bang.. mumble... inflationary expansion... mumble", but hardly anything "God-like".

    This nickname comes across as something dumb invented by the popular press in a half-assed attempt to communicate to regular folk how exciting the LHC is to us physicists.

    Maybe /. could lead the charge to kill this nickname?

    1. Re:Enough of the "God Particle" please by yomegaman · · Score: 5, Interesting

      I think it was Leon Lederman who coined it in his book. He is definitely a high-energy physicist, he was director of Fermilab for years and won a Nobel Prize for discovering the bottom quark. I agree with the sentiment, though, if I never heard it again it would be fine with me. I read the book some years ago but can't remember why he called it that.

      --
      ...wearing a skin-tight topless leather jumpsuit, with cutaway buttocks and transparent crotch panel.
    2. Re:Enough of the "God Particle" please by spun · · Score: 4, Informative
      --
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    3. Re:Enough of the "God Particle" please by kfort · · Score: 2, Insightful

      Mass generation is as God-like as it gets.

    4. Re:Enough of the "God Particle" please by turgid · · Score: 2, Insightful

      Unfortunately, "regular folk" who are interested in celebrity affairs, plasitc surgery and drug abuse ,pay for physics experiments.

      It's impossible to convince them how important such experiments are, so we need to patronise them.

    5. Re:Enough of the "God Particle" please by emm-tee · · Score: 3, Informative

      Maybe /. could lead the charge to kill this nickname That would be nice. It's correct name is the Higgs boson. http://en.wikipedia.org/wiki/Higgs_boson

      I'm amazed that currently no comment on this article contains the word "boson". I've heard it called the Higgs boson more times than I have the "god particle". Maybe it's just the media I choose to read/watch.
    6. Re:Enough of the "God Particle" please by SteelAngel · · Score: 3, Interesting

      The quarks are supposed to be named in pairs thusly:

      Up down

      Strange Charm

      Truth Beauty

      But somewhere in the 70's some particle group with little sense of wonder renamed Truth and Beauty to Top and Bottom, thus leaving Strange and Charm as sounding anachronistic.

    7. Re:Enough of the "God Particle" please by smolloy · · Score: 2, Interesting
      I'm not sure about that. The Higgs boson is a consequence of waves in the Higgs field, which strongly suggests that it isn't unvarying.

      Of course, I'm not an expert on this, so I'm prepared to be wrong.

  9. Breaking Physics News by Anonymous Coward · · Score: 2, Funny

    hey baby, wanna see my large hardon collider? I'll make you see the God particle.

  10. Re:Rumor/conjector by HiggsBison · · Score: 5, Funny

    I read the article on Higgs, and it is entirely conjecture based on specified rumor after rumor. Is this TMZ.com?

    Rumors? About me? *sigh* I'm always the last to hear of them.

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  11. Re:Dark Matter... by jmorris42 · · Score: 2, Insightful

    > Is it so hard to see that they're just dealing with the (luminiferous) (a)ether?!?

    Oh course. History doesn't repeat exactly but it does tend to rhyme. Is it any wonder that science falls prey to the same human failings since it IS just another human activity?

    --
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  12. Fermi and the Higgs by stox · · Score: 3, Interesting

    Sadly, 10% of Fermi's staff is being laid off, and the rest must take a mandatory week off of unpaid leave every two months due to the funding SNAFU at the DOE.

    --
    "To those who are overly cautious, everything is impossible. "
  13. Pioneer Anomaly by calidoscope · · Score: 2, Insightful

    I was a bit put off by the tone of TFA with respect to the Pioneer anomaly. While it is unlikely that the anomaly will disprove our models of gravity, it is an excellent example of a gap in our understanding of physics.

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    1. Re:Pioneer Anomaly by Protonk · · Score: 2, Interesting

      Well, let's be fair. the Pioneer anomoly is just that, anomalous. We don't see the impact in other situations, we don't have a good explanation for it and it isn't very large. It is entirely possible that this could be the same sort of anomaly as the orbit of Mercury or the Michelsonâ"Morley experiment. It's possible, but it is also possible that it falls into the category of experimental error.

      Please understand that the pioneer anomaly isn't treated in the same way as we remember (historically) anomalous results. No one disowned the researchers or completely dismissed their research. BUUUUTTTT...most of the explanations result in changes to the underlying framework of gravity (or alternatively, EM radiation) that don't really make sense. As far as we can tell it is better explained as an anomaly.

      Hopefully we are wrong and we discover something really awesome out there!

    2. Re:Pioneer Anomaly by Protonk · · Score: 2, Interesting

      Oh. Well that is an interesting problem. Keep in mind that the oort cloud isn't really as dense as we might think it would be. If we assume only regular matter (no dark matter), then the density of the oort cloud is fantastically low. It is higher than the density of space between the earth and Mars only because there isn't the tidal and graviational forces of a Jupiter like body to pull stuff out of it.

      Then, from a gravitational standpoint, we are looking at VERY small curvature imposed by the comets and such floating around. Moreover, it is probably not something that translates well into some net field. We can abstract it, think of the oort cloud as a uniform density object, but that abstraction doesn't hold well to the truth.

      If we WERE to abstract it, the well created by the oort cloud might just overcome that created by the sun at distances far away from the sun. But remember, that is a spherical cow evenly distributed with milk (har, har). The reason the oort cloud exists is because the comets and dust caught up in it are orbiting the sun. So we would have to imagine that the point where that influence wanes is very close to the edge of what we might call the oort cloud.

      Even IF that is the case, we would see the impact of such a well (again, keeping with our assuption of a uniformally distributed Oort cloud) on light coming into the solar system from outside it. Much like seeing like passing a star (gets 'lensed') is sort of like seeing light emanating from that star seeing light from outside the solar system would be like seeing light from inside the oort cloud. We would have been able to find this anomaly by looking at any infra-solar source than comparing it to light from outside the solar system.

      In the case of pioneer, we need to explain a slight red shift growing larger as pioneer gets further from earth. a red shift seen on BOTH probes but not from (as far as we can tell) any source other than those two probes. It's a pickle. :)

    3. Re:Pioneer Anomaly by sturle · · Score: 2, Informative

      The plutonium source in Pioneer emits 2000W of heat. If only 64W of that heat is radiated asymmetrically away from Pioneer, that will explain the whole anomaly. This is perfectly understandable, and it is even very likely that the heat dissipates a little bit unevenly from Pioneer. You don't need to change the theory of gravity to explain this. Reference here: http://66.102.1.104/scholar?hl=en&lr=&q=cache:Yw3pMm306akJ:www.aanda.org/articles/aa/full/2007/07/aa5906-06/aa5906-06.right.html+

  14. Something doesn't fit...like.... by 3seas · · Score: 2, Funny

    ....the god particle????

    Is god that small?

  15. Re:Dark Matter... by Tenebrousedge · · Score: 4, Informative

    I would post that sort of nonsense as an AC, too. For those that are unaware, the theory of a luminiferous aether posits that there exists some sort of medium in interstellar space which conducts light. It was completely superseded around the beginning of the last century, mostly by the theories of a man named Einstein. Which explain quite well our observations of the universe on a large scale. Dark matter is an entirely unrelated question related to the amount of matter in the universe. Dark energy, zero-point field...you're just throwing around terms. What we know about the forces in the universe is not exhaustive, but to invent a completely new one just to account for a minor anomaly is not good science. What you are doing here is the equivalent of fighting for the Flat Earth theory, and it disturbs me to see that modded informative here...

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  16. Re:Dark Matter... by ceoyoyo · · Score: 2, Interesting

    The Higgs field and dark energy are about the closest things directly comparable to the aether in modern physics. Dark matter is very different: it clumps, so it isn't everywhere.

  17. Re:Rumor/conjector by dintech · · Score: 2, Funny

    That's just the creationists. Everyone else is fine with it.