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The Pioneer Anomaly & Other Breaking Physics News 100

Posted by kdawson
from the explaining-the-unseen dept.
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.
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The Pioneer Anomaly & Other Breaking Physics News

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  • Sloppy editing (Score:5, Insightful)

    by Harmonious Botch (921977) * on Sunday April 13, 2008 @02:33PM (#23055422) Homepage Journal
    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?
    • by Anonymous Coward on Sunday April 13, 2008 @02:41PM (#23055462)

      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.

    • by Valdrax (32670) on Sunday April 13, 2008 @02:44PM (#23055466)

      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.
      • Re: (Score:2, Insightful)

        by McGiraf (196030)
        self fulfilling prophecy
      • by Anonymous Coward on Sunday April 13, 2008 @03:20PM (#23055624)
        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.
        • by barath_s (609997) <[barath.sundar] [at] [gmail.com]> on Sunday April 13, 2008 @06:13PM (#23056834)
          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 [wikipedia.org] The issue is that the current best guesses for these effects do not yet account for the anomaly.
          • by Tablizer (95088)
            It seems to me it would be fairly easy to test the anomaly. The craft merely has to transmit "dumb" radio beeps. Sputnik-like even. Have a capacitor that stores up power from a weak nuclear-decay source and beeps off every few minutes. Because of the limited functionality, it may weigh say 10 pounds, meaning its relatively cheap to launch. I'm not sure it even needs to be a directional antenna.
          • Re: (Score:1, Insightful)

            by Anonymous Coward
            data were collected...
        • by IdleTime (561841)
          Now, what of we have failed to notice that gravity comes in two forms too, the weak and the strong gravitational force?

          The strong gravitational force is what we see the effect of on a daily basis, the weak is so weak it only is seen on large scale structures and the effect of it on Pioneer is the combined weak gravitational field from the inner solar system bodies working on the probe?
      • Re: (Score:2, Funny)

        by Anonymous Coward
        buried under senseless meme-tossing

        In soviet russia, memes toss you!
        • Re: (Score:1, Funny)

          by Anonymous Coward
          In Korea, only old tossers use memes!
      • (or other off-topic) ranting.
        like your post?
      • Re: (Score:3, Insightful)

        by PopeRatzo (965947) *

        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?
  • I read the article on Higgs, and it is entirely conjecture based on specified rumor after rumor. Is this TMZ.com?
    • Re:Rumor/conjector (Score:4, Informative)

      by FooAtWFU (699187) on Sunday April 13, 2008 @02:52PM (#23055506) Homepage

      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?
    • Re:Rumor/conjector (Score:5, Informative)

      by yomegaman (516565) on Sunday April 13, 2008 @03:07PM (#23055572)
      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.
    • by evil agent (918566) on Sunday April 13, 2008 @03:12PM (#23055602)
      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...
    • by HiggsBison (678319) on Sunday April 13, 2008 @03:51PM (#23055778)

      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.

  • Before LHC though? (Score:4, Interesting)

    by stevedcc (1000313) * on Sunday April 13, 2008 @02:52PM (#23055504)
    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.
    • by yomegaman (516565) on Sunday April 13, 2008 @03:00PM (#23055540)
      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.
      • Re: (Score:2, Funny)

        by maxwell demon (590494)

        and so far we are not seeing any excess of events there, but in fact somewhat fewer events than expected.

        So you are seeing Anti-Higgs? :-)
      • by bockelboy (824282) on Sunday April 13, 2008 @04:19PM (#23055930)
        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.
  • by smolloy (1250188) on Sunday April 13, 2008 @03:21PM (#23055626)
    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?

    • by yomegaman (516565) on Sunday April 13, 2008 @03:28PM (#23055652)
      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.
      • by smolloy (1250188)

        ...He is definitely a high-energy physicist, he was director of Fermilab for years and won a Nobel Prize for discovering the bottom quark....

        Ooops. Now I'm embarrassed. Got that pretty wrong, didn't I? :S

        I still think it's a crap nickname though.

        • by Sique (173459)
          But hey - charm quark. What the heck a name is that?
          (Especially for a German like me... where quark means white cheese.)

          God particle is not much worse.
          • Re: (Score:3, Interesting)

            by SteelAngel (139767)
            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.
            • by JamesP (688957)
              Then if they discover a new pair of quarks it will be called VIM and EMACS then??
          • by Muad'Dave (255648)
            The name "Quark" came from the story Finnegan's Wake [wikipedia.org] by James Joyce.

            From the wikipedia article:

            The phrase "Three quarks for Muster Mark" on page 383 of Finnegans Wake is the origin of the spelling given by physicist Murray Gell-Mann to quarks, a type of subatomic particle.[88] (In the novel, the phrase is sung by a chorus of seabirds, and probably means 'three cheers' or--judging from Joyce's notes--three jeers.)

        • by ceoyoyo (59147)
          It actually isn't such a bad name, except for the unfortunate resonance with some silly people. At the time it was coined those people weren't as high profile, so it was more like "God doesn't play dice."

          The Higgs field is supposed to suffuse everything. We're constantly immersed in it, and it is responsible for both some of the fundamental properties of the basic constituents of the universe and its largest features. That is, it sticks its fingers in pretty much everything.
          • by smolloy (1250188)

            The Higgs field is supposed to suffuse everything. We're constantly immersed in it, and it is responsible for both some of the fundamental properties of the basic constituents of the universe and its largest features. That is, it sticks its fingers in pretty much everything

            Qui-Gon Jinn? Is that you?

            Actually, the fact that the Higgs field is universal makes it much like gravity or electromagnetism. Theoretically, these fields extend to infinity, and, especially in the case of gravity, have/had a very profound effect on the evolution of the Universe. Perhaps gravitons should be considered the "God Particle"?

            • by ceoyoyo (59147)
              The Higgs field is supposed to be the same everywhere. Unvarying, and an intrinsic part of space itself. Gravity is associated with a very obvious and material cause.
              • Re: (Score:2, Interesting)

                by smolloy (1250188)
                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.

      • It was originally known not as the God particle but the "Oh my God" particle- As in "Oh my god, that single particle had the kinetic energy of a falling brick!"

        More here-
        https://www.fourmilab.ch/documents/OhMyGodParticle/ [fourmilab.ch]

        -b
        • by Luyseyal (3154)
          No. That Fermilab article specifically says the "Oh My God" Particle was a "proton with an energy of 3.2±0.9×10^20 electron volts."

          -l
    • by spun (1352) <loverevolutionary@@@yahoo...com> on Sunday April 13, 2008 @03:29PM (#23055654) Journal
      Its from the book The God Particle: If the Universe Is the Answer, What Is the Question? [wikipedia.org]. It's a joke, son, laugh.
    • Re: (Score:2, Insightful)

      by kfort (1132)
      Mass generation is as God-like as it gets.

    • by Plazmid (1132467)
      Dude, I think you fail to recognize what understanding mass means. Mass is just so fundamental. Just about everything has it.
      • by smolloy (1250188)
        That's why I said, "to communicate to regular folk how exciting the LHC is to us physicists"

        It *is* exciting. I just think that the nickname is dumb.

    • Re: (Score:3, Insightful)

      by turgid (580780)

      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.

    • Re: (Score:3, Informative)

      by emm-tee (23371)

      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 [wikipedia.org]

      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.
    • Anyone who can get Joe and Jane Public to pony up billions of dollars to create a particle that lasts for a billionth of a second is God in my books. Let God name his particle.
  • by Anonymous Coward
    hey baby, wanna see my large hardon collider? I'll make you see the God particle.
  • Sweet! These breakthroughs bring us ever closer to a portal gun.
  • Dark Matter... (Score:1, Informative)

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

    See Tesla [1][2], Lyne[1], Silvertooth[3] and many others.

    Oh, but aether has become a term that is a no-no.. so let's call it dark energy, dark matter, the zero point field, etc.

    Currently no university is teaching the real work of Maxwell, but rather the simplified (and lacking!) version by Heaviside.

    [1] http://netowne.com/technology/important/ [netowne.com]
    [2] http://www.bibliotecapleyades.net/tesla/occultether/occultether.htm [bibliotecapleyades.net]
    [3] http://ww [unusualresearch.com]
    • Ahem, has it been peer reviewed?
    • Re: (Score:3, Insightful)

      by jmorris42 (1458) *
      > 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?
    • by Protonk (599901)
      It is hard to see that because they AREN'T just dealing with the aether. This isn't some substrate at rest upon which the motions of the galaxy play out. I know it is comforting to take refuge in crackpot science, but there really isn't a zero speed reference frame. It doesn't exist. I'm sorry.
    • Re:Dark Matter... (Score:4, Informative)

      by Tenebrousedge (1226584) <tenebrousedgeNO@SPAMgmail.com> on Sunday April 13, 2008 @06:46PM (#23057130)
      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...
    • Re: (Score:3, Interesting)

      by ceoyoyo (59147)
      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.
  • Fermi and the Higgs (Score:4, Interesting)

    by stox (131684) on Sunday April 13, 2008 @04:15PM (#23055898) Homepage
    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.
    • by barath_s (609997)
      The funding fiasco [http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=1D650F43-3048-8A5E-106FD610574B73C8] impacts more [http://www.hpcwire.com/hpc/2153825.html ] than just this slim chance to find the Higgs
    • by schmiddy (599730)

      I was a little shocked to read the parent post, but he's absolutely right. See the story (from December) here: http://www.nytimes.com/2007/12/22/science/22fermi.html?_r=1&oref=slogin [nytimes.com]

      However, I'm not sure I'd characterize the cuts as a "funding SNAFU". According to the NYTimes article, the cuts were "to meet bottom-line spending targets demanded by Mr. Bush, Congress rolled back the planned increases for the Energy Department and other science agencies." If I were more cynical I'd say that money jus

  • Pioneer Anomaly (Score:3, Insightful)

    by calidoscope (312571) on Sunday April 13, 2008 @05:12PM (#23056320)
    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.
    • Re: (Score:3, Interesting)

      by Protonk (599901)
      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) an
      • by Baron_Yam (643147)
        My Newtonian physics is a little weak - does the effect of gravity within a sphere change as you travel from the center to the surface?

        I'm wondering whether the Pioneer Anomaly can be explained by the Oort cloud. /Hey, I may be ignorant, but I'm ASKING, right?
        • by Protonk (599901)
          kind of. Imagine gravity as a vector field pointing toward the center of the celestial body (assuming here that the body is a point mass). So as you move from the center to the surface, the vector field appears to be less and less curved--you go from seeing things flow like they would into a funnel (where you are close to the source) to seeing a field that effectively looks like it is perpendicular to the surface. Again, this assumes that you have a point mass. but this is basically why you can do those
          • by Baron_Yam (643147)
            I was thinking of the Oort cloud as the surface of a sphere - would there be a lessening of gravitational effect while inside the sphere (because some of the mass is still ahead of you) followed by an increase once you passed it?

            Or, does it all effectively balance out at the center of the sun as far as the math is concerned...
            • Re: (Score:3, Interesting)

              by Protonk (599901)
              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 a
        • by ceoyoyo (59147)
          The Oort cloud would have to have a lot of mass in it to have much effect, and you wouldn't see much effect until a good part of that mass was between you and the sun.
        • by Zelrak (1213628)
          To answer your orignial question, the gravity in a hollow sphere is zero everywhere inside it and as if it was all concentrated at the center if you are outside it.

          So the gravity of a sphere at some point in it is the same as if you had all the mass of radius less than the point concentrated at the center.

          Basically, as you travel outwards from the center of a sphere of matter the gravity increases.(Mass grows like r^3 so gravity grows like r)

          -----------

          Note: all this assumes that I remember my classi

          • In other words, if you assume that the mass of the Oort cloud is distributed evenly across a sphere, it would have no gravitational impact on anything inside of the cloud. It won't "pull" something on the inside out toward it.
    • It's kind of like the Schwarzchild radius. Instead of slowing down and being forever entrapped by the immense gravitational point source of the black hole, it's like being entrapped in the immense graviational field of a sun.

      No, wait....
      • by Protonk (599901)

        It's kind of like the Schwarzchild radius. Instead of slowing down and being forever entrapped by the immense gravitational point source of the black hole, it's like being entrapped in the immense graviational field of a sun.

        No, wait....
        Or it's like the doppler effect, except it is really small and happens only over long distances but we don't see it too far away because.....

        no, wait.... :)
    • Re: (Score:2, Informative)

      by sturle (1165695)
      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+ [66.102.1.104]
    • by jo42 (227475)
      Frankly, I surprised that no one has offered up the possibility of an RFID tag attached to Pioneer by The Department Of Immature Civilizations Space Junk Tracking Division of The LGMs [wikipedia.org].
  • by 3seas (184403) on Sunday April 13, 2008 @05:54PM (#23056676) Journal
    ....the god particle????

    Is god that small?
  • As this [66.102.1.104] old article shows, thermal radiation can easily explain all of the Pioneer anomaly. Trying to show this by making a thermal model of the spacecraft is an interesting approach, but how well will they be able to model how the harsh environment of space, with all kinds of rays and particles from the sun and elsewhere are continuously bombarding the spacecraft form all directions? Just a small discoloring or formation of chemical substances on the surface will greatly influence how the heat is dissip

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