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Science

"Perfect" Electron Roundness Bruises Supersymmetry 150

Posted by samzenpus
from the look-at-how-round-it-is-man dept.
astroengine writes "New measurements of the electron have confirmed, to the smallest precision attainable, that it has a perfect roundness. This may sounds nice for the little electron, but to one of the big physics theories beyond the standard model, it's very bad news. 'We know the Standard Model does not encompass everything,' said physicist David DeMille, of Yale University and the ACME collaboration, in a press release. 'Like our LHC colleagues, we're trying to see something in the lab that's different from what the Standard Model predicts.' Should supersymmetrical particles exist, they should have a measurable effect on the electron's dipole moment. But as ACME's precise measurements show, the electron still has zero dipole moment (as predicted by the standard model) and is likely very close to being perfectly round. Unfortunately for the theory of supersymmetry, this is yet another blow."
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"Perfect" Electron Roundness Bruises Supersymmetry

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  • ACME (Score:5, Funny)

    by Tablizer (95088) on Friday December 20, 2013 @01:37AM (#45743465) Homepage Journal

    "ACME collaboration"?

    Then just bang the electron on the head with an ACME anvil, and it will grow lumps.

  • by Anonymous Coward on Friday December 20, 2013 @01:47AM (#45743501)

    If you measure it, an electron is perfectly round. The rest of the time it's kind of oval.

  • by EmperorOfCanada (1332175) on Friday December 20, 2013 @01:51AM (#45743509)
    I have been on the edge of my seat waiting for something genuinely new. Something like when people were discovering that atoms were made up of even tinier bits. Or that quantum was not just a mathematical nicety but way cooler. Each of these fairly "academic" discoveries then opened up whole new trains of thought that led to lasers, solid state electronics, nuclear reactors, etc.

    So what wonderful physics is hiding out there waiting to be discovered and open up a whole new world to us?

    Personally my biggest recent letdown were the FTL neutrinos that turned out to be bogus. I was genuinely hoping that something cool revealing itself. But alas. My favorite today is that entanglement and wormholes might have some relationship. Minimally that will result in some cool sci-fi if not actual science.

    Personally I don't mind if ultraspherical electrons shut down a bunch of pet theories. They didn't seem to be making much progress and thus the door has been opened to explore something new. Maybe there is some guy trying to get his doctorate showing that supersymmetry is a load of rubbish but hasn't been able to get much traction because the entire panel got their doctorates in supersymmetrical related ideas and in order to defend his thesis he has to first set fire to theirs.
  • by Anonymous Coward on Friday December 20, 2013 @01:55AM (#45743517)

    Science is going to be really screwed when they discover frictionless planes also exist.

  • If it's spherical what's the size of that sphere?
    • Re: (Score:2, Informative)

      by Anonymous Coward

      radius: 2.8179403267e-15 m

      surface: 9.9786881e-29 m^2

      volume: 9.3731159e-44 m^3

      above in fuzzy logic: very tiny

      • Re: (Score:2, Informative)

        by Anonymous Coward

        radius: 2.8179403267e-15 m

        That is the classical answer. It is generally considered to be a point particle today.

        • Stupid question about a "point" particle: The minimal size (diameter?) for anything would then be a Planck length, right?
    • Uhm, haven't you heard? Size doesn't matter.
    • The summary and articles are a little vague about what the "shape" of an electron is supposed to be. As are as we know, an electron is a point particle, meaning it has zero size. What these scientists mean by "spherical" is that the electron's electric field is perfectly spherically symmetric (measured to a higher degree of accuracy than any previous measurement). This means that if you imagine a sphere with an electron at the center, then the electric field of the electron is exactly the same magnitude

  • by Greyfox (87712) on Friday December 20, 2013 @02:03AM (#45743549) Homepage Journal
    Every time I see a news item about supersymmetry, it always seems to be disproving it. Seems like the only thing the hypothesis has going for it is the universe would make a lot more elegantly designed if it was true. It seems like mostly wishful thinking to me.
    • by bondsbw (888959)

      The more we learn about the reality of the universe, the more we'll come to respect its true elegance and to see how inelegant our prior theories (like supersymmetry) were.

      • by Anonymous Coward

        Is that a religious statement? What if the universe is ugly, way deep down?

        • by Anonymous Coward

          As long as it still puts out

        • by Anonymous Coward

          In all serious, I've always wondered what discoveries might not be made because of so many scientists insisting on theories that are "elegant". The universe does not appear to give a damn about what humans think is or is not elegant.

      • by fatphil (181876) on Friday December 20, 2013 @05:38AM (#45744079) Homepage
        But the proponents of SuSy claim that their theories are elegant!

        Have you ever seen a Nima Arkani-Hamed talk? (there are some on youtube and elsewhere). Most annoying is that not only does he rant and rave about how wonderfully simple and elegant his supersymmetry is, but he decorates those claims with embellishments like "they must be true".

        Even more annoying is when a big potentially-confirming experiment is concluding, he's proud to say what result he expect that will confirm this theories, add that if he doesn't get them he'll scrap his theories, and then when the results don't confirm his theories, he shuts the fuck up briefly, and then resumes pushing the same old theories.

        If you want good science. Don't look in the direction of that branch of physics, you'll have more luck in psychotherapy, economics, or astrology.
        • But the proponents of SuSy claim that their theories are elegant!

          Yeah, it's elegant except for all the magical unbroken superpartners that are too energetic to exist.

        • ...he shuts the fuck up briefly, and then resumes pushing the same old theories...

          Oh, he'll come a"round" eventually!

      • Well it's been suggested that some of the Supersymmetric particles might be an explanation for Dark Matter which does appear to exist. Other than that, I'm not sure that Supersymmetry has much going for it these days.

    • by sjames (1099) on Friday December 20, 2013 @05:04AM (#45743997) Homepage

      It's a little more involved. We know that the standard model is unable to explain a few important observations (such as gravity) so it *can't* be the whole story. Any theory that accounts for gravity and dark matter/energy will be more elegant by virtue of not having holes in it.

      Supersymmetry could explain those things and fortunately makes a few predictions that we are now capable of testing. However, those aren't panning out so it must be revised and tested again. At least until someone comes up with something better to test.

      • by Anonymous Coward

        Supersymmetry could explain those things and fortunately makes a few predictions that we are now capable of testing. However, those aren't panning out so it must be revised and tested again.

        Isn't that how people dealt with the theory that planets move on perfect circles? Instead of throwing the theory out once it was shown that there was no evidence for it and a lot of evidence against it they adapted it until it became impossible to describe (planets move on circles that move on circles - circles all the way down). How much money do you invest into a failed and disproven theory before resources are moved to research a different explanation?

        • by Anonymous Coward

          Sometimes visualising something in the wrong way is the first step to figuring out what the right way is.

          • More importantly, there's no requirement in physics that the universe be elegant for it's theories easy to understand. It's perfectly plausible that planets could move on circles and on other circles and so on and so forth. Of course all this was being done in the Roman times and was an effort in keeping the Earth at the center of the universe, but if the OP notes he thinks money should be moved elsewhere then I ask where - we need better theories of the universe, and the other candidates are at the exact s

        • by Anonymous Coward
          An ellipse can be modeled as an infinite series of circles on circles. Neither model is more correct. Eventually we ended up with calculus for explaining orbits, which involves computing the answers for an infinite series. Even today, we can't model more than two bodies without computing a nearly infinite series. I say "nearly", but truthfully, unless you do an infinite number of computations, you're just approximating an orbit with more than two bodies. So, you can mock people for coming up with the b
        • by sjames (1099)

          Keep in mind that Copernicus was working with epicycles when he developed the heliocentric model. I would call that worthwhile. I would argue that had he not "invested money into a failed and disproven theory", he would not have had his important insight. In turn, Kepler couldn't have discovered the laws of planetary motion had he been stuck in a geocentric model.

  • The Wikipedia article on supersymmetry [wikipedia.org] did not really seem to help within the context of the electron smoothness issue.
  • by Anonymous Coward on Friday December 20, 2013 @02:26AM (#45743625)

    ... of models involving perfectly spherical atoms, nanoparticles, cows, planets, stars, etc, there is something ironic about an electron being too round.

  • I thought that, since it wasn't made up of sub-particles, an electron was a point particle. Since when does it have a defined size, let alone shape?
    • Isn't a point a perfect sphere? In fact the most perfect sphere possible?

      • Isn't that a rather pointless conjecture?

        • by Anonymous Coward

          Yes, but isn't it a well rounded explanation?

      • by Anonymous Coward

        Isn't a point a perfect sphere? In fact the most perfect sphere possible?

        A point has no dimension at all.
        When scientists say that the electron ia a point like particle they mean that the dimensions of the electron are negligeable with respect to the other characteristic lengths in play. But of course an electron as every other physical object is 3 dimensional in nature.

        • A sphere has to have dimensions?

          I would have thought being 0 in all dimensions made for a perfect sphere, I mean, hey, its not a cube is it?

        • No, it does not have negligible dimensions, and they are not just smaller than Planck length, they are exactly zero, according to this theory. I.e. each elementary particle (incl. electrons and quarks of which all matter is made) is a tiny force field originating from an invisible (so to speak, or maybe better said immaterial) point in space. Mass is a property of that field given by the Higgs Boson.

          It kind of makes sense, b/c if it were solid i.e. had some volume and was made of "stuff" then it wouldn't be

    • Re: (Score:3, Insightful)

      by Twinbee (767046)
      I assume they mean the force created by the electron is perfectly round, rather than the particle itself. Perhaps someone can confirm.
  • by bickerdyke (670000) on Friday December 20, 2013 @04:05AM (#45743855)

    How can anything have a shape that turns into an electromagnetic wave when you're not watching...

    • I think we call them quantum states....

    • How can anything have a shape that turns into an electromagnetic wave when you're not watching...

      The Doctor: Don't blink. Blink and you're dead. They are fast. Faster than you can believe. Don't turn your back. Don't look away. And don't blink. Good Luck.

    • by Anonymous Coward

      They don't. Would violate conservation of charge and spin. You're probably confusing electrons and photons.

      In fact, quantum theory was invented when it was realized that Maxwell's equations required electrons in orbits to emit electro-magnetic waves as they spiral towards the nucleus. They of course don't do either.

  • A perfect sphere IS super-symmetrical so long as the cut goes through the center. Good thing I'm here to help out these scientist.
  • by Required Snark (1702878) on Friday December 20, 2013 @06:02AM (#45744145)
    String theory is strongly linked to supersymmetry, If supersymmetry is not found experimentally then string theory becomes much less likely. The current alternative to string theory is loop quantum gravity.

    http://en.wikipedia.org/wiki/Supersymmetry [wikipedia.org]

    For string theory to be consistent, supersymmetry appears to be required at some level (although it may be a strongly broken symmetry). In particle theory, supersymmetry is recognized as a way to stabilize the hierarchy between the unification scale and the electroweak scale (or the Higgs boson mass), and can also provide a natural dark matter candidate. String theory also requires extra spatial dimensions which have to be compactified as in Kaluza-Klein theory.

    Loop quantum gravity (LQG) predicts no additional spatial dimensions, nor anything else about particle physics. These theories can be formulated in three spatial dimensions and one dimension of time, although in some LQG theories dimensionality is an emergent property of the theory, rather than a fundamental assumption of the theory. Also, LQG is a theory of quantum gravity which does not require supersymmetry. Lee Smolin, one of the originators of LQG, has proposed that a loop quantum gravity theory incorporating either supersymmetry or extra dimensions, or both, be called "loop quantum gravity II".

    A whole lot of PhD dissertations, physics publications, and academic careers are on the line over this. String theory is the current favorite and loop quantum gravity the underdog. The direction of theoretical particle physics could be radically altered if the LHC doesn't find evidence of supersymmetry.

    • by Sponge Bath (413667) on Friday December 20, 2013 @10:15AM (#45745125)

      A whole lot of PhD dissertations, physics publications, and academic careers are on the line over this.

      All those (dipole) moments will be lost in time... like tears in rain...

    • by msobkow (48369)

      Thank you!

      Finally someone took the time to provide a concise explanation of WTF it means for supersymmetry to be disproven.

    • by Jmac217 (3006299)
      Well that's the sad truth when basing hypothesis on unproven theories. If Supersymmetry flops, as a whole, it doesn't necessarily mean that we start over from scratch. There could be some truth to each theory even though certain aspects fall through. Physics is about knowing physical law, not wishing it into existance. Wishful thinking only takes us so far and eventually conclusions need to be determined. Well it seems we're getting near the point of drawing conclusions. Picking up the working pieces of bus
      • by matfud (464184)

        A hypothosis does not require any theory or fact to define it. It is postulated so that it can be tested. If it fails the tests it needs to be revised or disarded. If it explains many observations then it may become a theory.

        Oddly supersymettry is not one concept. There are many flavours. They may all be wrong. Some may be less wrong than others.

        If you don't have people comming up with the concepts then you have little to design an experiment to test.

  • The Standard Model doesn't predict that the electron EDM is zero.
  • smallest precision attainable does not mean what you think it does. You meant highest precision attainable
    • smallest precision attainable does not mean what you think it does. You meant highest precision attainable

      Hmm. Many existing laws are based on assumption that lower precision is correlated with highness... If you're right, it could spell trouble for prohibition.

  • Electrons are point particles - modelled as zero-volume and massless. They might have no physical form. I am not surprised that our measures of them indicate perfect symmetry.

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