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Physicists Test Symmetry Principle With an Antimatter Beam 106

Posted by samzenpus
from the what-does-it-look-like-over-there? dept.
Hugh Pickens DOT Com writes "Jon Butterworth has an interesting article at The Guardian about the idea of standpoint-independence in physics and the absence of 'privileged observers.' The ASACUSA experiment at CERN plans to make a beam of antimatter, and measure the energy levels as the beam travels in a vacuum, away from the magnetic fields and away from any annihilating matter. The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time. In string theory for example it is possible to violate this principle so the ASACUSA people plan to measure those antihydrogen energy levels very precisely. Any difference would mean a violation of CPT inversion symmetry. Physicist Ofer Lahav has some interesting observations in the article about how difficult it is these days for physicists to develop independent points of view on cosmology. 'Having been surrounded by a culture in which communication is seen as generally a good thing, this came as a surprise to me, but it is a very good point,' writes Butterworth. 'We gain confidence in the correctness of ideas if they are arrived at independently from different points of view.'

A good example is the independent, almost simultaneous development of quantum electrodynamics by Richard Feynman, Julian Schwinger and Sin-Itiro Tomonaga. They all three had very different approaches, and Tomonaga in particular was working in wartime Japan, completely cut off from the others. Yet Freeman Dyson was able to prove that the theories each had provided for the quantum behavior of electrons and photons were not only all equally good at describing nature, but were all mathematically equivalent — that is, the same physics, seen from different points of view. Whether we are using thought experiments, antimatter beams, sophisticated instrumentation, or sending spaceships to the outer solar system, Butterworth says the ability for scientists to loosen the constraints of our own point of view is hugely important. 'It is also, I think, closely related to the ability to put ourselves into the place of other people in society and to perceive ourselves as seen by them — to check our privilege, if you like. Imperfect and difficult, but a leap away from a childish self-centeredness and into adulthood.'"
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Physicists Test Symmetry Principle With an Antimatter Beam

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  • wth (Score:5, Funny)

    by Impy the Impiuos Imp (442658) on Monday March 03, 2014 @09:11AM (#46386849) Journal

    What's this icky nerd stuff doing on a political web site like Slashdot?

  • by Anonymous Coward
    Seems like there are a lot more interesting uses for an antimatter beam. Let's take solving the situation in the Ukraine, for example.
  • Cambridge Dogma (Score:2, Insightful)

    by globaljustin (574257)

    What I found most interesting is what the head researcher found interesting:

    Physicist Ofer Lahav has some interesting observations in the article about how difficult it is these days for physicists to develop independent points of view on cosmology

    In other words: Cambridge (Hawking) Dogma

    Cosmology has become a branding exercise for universities & their long research grant coat tails. It has been, in my view, hijacked by ideologically/branding driven pseudo-science that seeks to purvey an institutional v

    • by Megol (3135005)
      I think you at least could link or describe alternative theories and/or researchers that doesn't follow this "pseduo-science".

      As is now my kook detector is nearly exploding (with delight).

    • Re: (Score:3, Insightful)

      by UnknownSoldier (67820)

      Max Plank back in 1984 noticed how Science had become Dogmatic / Religious when he said:

      A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.

      Which can be paraphrased as:

      "Science advances one funeral at a time."

      Science was never about the pursuit of Truth, but about the Removal of Falsehood. Unfortunately far too many scientists have their sacred cows that the

      • by Anonymous Coward

        Max Planck the black body research physicist was dead in 1984. Perhaps you meant 1894?

        • Thanks for the catch. Freudian slip, dyslexia, etc.. Meant 1948.

          Lots of good quotes http://en.wikiquote.org/wiki/M... [wikiquote.org]
          i.e.
          Wissenschaftliche Selbstbiographie. Mit einem Bildnis und der von Max von Laue gehaltenen Traueransprache. Johann Ambrosius Barth Verlag (Leipzig 1948), p. 22, as translated in Scientific Autobiography and Other Papers, trans. F. Gaynor (New York, 1949), pp. 33â"34 (as cited in T. S. Kuhn, The Structure of Scientific Revolutions).

      • Re:Cambridge Dogma (Score:4, Insightful)

        by Baloroth (2370816) on Monday March 03, 2014 @11:18AM (#46387543)

        Except that's not really true. Our current Big Bang cosmological theory rose into the forefront (despite being derisively named the "Big Bang" by the proponents of the earlier reigning cosmological theory of the steady-state universe) when the cosmic microwave background was discovered. Quantum mechanics is the reigning theory for explaining particle behavior at very small scales, despite Einstein's well-known dislike for the theory. The fact is: you don't have to convince your opponents, you have to convince everyone else. It doesn't matter if you have a bunch of scientists unwilling to give up their "sacred cows", because you have a bunch of other scientists who have no stake in one theory or the other but are perfectly capable of judging between the evidence. Thats really the key: scientific progress is made by the community testing and accepting theories. Of course, some people (like Hawking) have a significant influence, but it's not like Hawking is never willing to admit he's wrong either: he has famously made several bets with John Preskill/Kip Thorne about singularities and black holes, which he has lost (and admitted to losing).

        • by ceoyoyo (59147)

          It's never been true. It's a myth spouted by people who've had their pet theories shot down by people who rightly want more evidence.

      • Others have challenged you on this, but those same techies would agree that old tech never dies, it just co-exists alongside new tech. The same happens in physics.

        What amazes me the most is how people will go off and try to prove some conjecture of some theory...when the larger theory has massive flaws. It smacks of graduate students and research dollars.

        At least part of the cause, IMO, is that simple things are small, and complex broken things are big. And there is a lot of time to fill in a 45 minut
      • "Science advances one funeral at a time."

        this is an amazing quotation...i hope its not true, but what a way to express a complex situation with simple terms

      • It can only disprove false ones.

        From time to time I read - especially here at /. - that string theory is bogus because it is not falsifiable.

        G-d Almighty Himself didn't create the Universe for the benefit of scientists. Just because a theory cannot be falsified, does not mean it is incorrect. It means we just don't know.

    • Re:Cambridge Dogma (Score:5, Interesting)

      by PvtVoid (1252388) on Monday March 03, 2014 @10:51AM (#46387377)

      Whoah. Are you even remotely aware of what is being done in cosmology these days?

      Planck [esa.int] Sloan Digital Sky Survey [sdss3.org]
      Square Kilometer Array [skatelescope.org]
      Ice Cube [wisc.edu]
      Large Synoptic Survey Telescope [lsst.org]
      Euclid [esa.int]

      Hardly "ideologically/branding driven pseudoscience". Who the hell modded you up?

      • Yes I'm remotely aware...

        IANAC but its close enough to my research area (information science) that I keep up on 'the literature' as best I can

        I am actually more of a 'fan' of cosmology. From a young age I was obsessed with space & cosmology asks alot of fun questions.

        Look, it's not *only* Cambridge, and not everyone at Cambridge is evil, and I didn't say cosmology was evil...that's all overreaction

        Hawking is totally trolling...that's not equivocation that's fact...but even though I'm a critic I must adm

    • Re:Cambridge Dogma (Score:5, Interesting)

      by SpankiMonki (3493987) on Monday March 03, 2014 @12:13PM (#46387903)

      What I found most interesting is what the head researcher found interesting:

      Physicist Ofer Lahav has some interesting observations in the article about how difficult it is these days for physicists to develop independent points of view on cosmology

      In other words: Cambridge (Hawking) Dogma

      Ofer Lahav didn't say anything of the sort. What Lahev said was the reason for non-independent viewpoints was "...these days we communicate continuously and too much. Developing independent points of view on cosmology, or indeed other matters, is therefore very difficult." - which has nothing to do with "Cambridge (Hawking) Dogma" (or anybody else's dogma for that matter).

      Perhaps you didn't read TFA and simply decided you "knew" what Lahev was referring to just by reading the summary. In other words: you put words in Lahev's mouth to validate your fear of pervasive "ideologically/branding driven pseudo-science". In any case it looks like you have some ax to grind - and given the mods, you're not alone.

      • Obviously you're not used to reading scientific literature.

        It's...ahem...kind of dry at times. He was choosing his words carefully.

        No he doesn't mention Cambridge or Hawking by name. That I added of course, but I didn't just randomly pick a university & cosmologist...those are good examples of my point.

        • Obviously you're not used to reading scientific literature.

          It's...ahem...kind of dry at times. He was choosing his words carefully.

          I guess you have a different understanding than I of what constitutes scientific literature. Personally, I don't believe the Guardian article where you've taken Lahav's quote qualifies as scientific literature, but perhaps you do. You seem to be saying as much.

          No he doesn't mention Cambridge or Hawking by name. That I added of course...

          ...along with an assertion that what Lahav was really saying was that there's pseudo-scientific dogma that's holding back science. Are you aware of Lahav making such statements in the past? Perhaps you've spoken with Lahav on the matter?

          ...but I didn't just randomly pick a university & cosmologist...those are good examples of my point.

          Who (besi

  • Anyone else read that and hear Charlie Brown's teacher in their heads?
    • by Hentai (165906)

      No, but I reached "beam of pure anti-matter" and started reading it in Richard O'Brien's voice.

  • by Anonymous Coward

    Whether we are using thought experiments, antimatter beams, sophisticated instrumentation, or sending spaceships to the outer solar system, Butterworth says the ability for scientists to loosen the constraints of our own point of view is hugely important.

    That's why I failed at physics. My thought experiments always ended up with me surrounded by beautiful naked women.

  • Last post! (Score:5, Funny)

    by K. S. Kyosuke (729550) on Monday March 03, 2014 @09:44AM (#46387017)

    The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time.

    Uh...last post, anyone?

  • in string theory so I'm not sure that has any relevance.

  • by Intrepid imaginaut (1970940) on Monday March 03, 2014 @09:58AM (#46387085)

    I don't like, actually. While I generally agree that a new orthodoxy is bad news in science and scientists shouldn't fear being shunned for putting forward new theories which go against that orthodoxy, I find it disturbing that the language of murky social engineering is finding its way into "scientific" commentary. The only people I've ever heard talk like that are those interested in equality of outcome, not of opportunity, which is pretty much the opposite of science.

    • by Anonymous Coward

      Strange stance, given that equality of opportunity has never existed, and in a literal sense, "equality of outcome" (i.e. death) is scientific fact.

      But, I'll bite... how is trickle-down "scientific" and redistribution the "opposite of science"? Seems science has no reason to be other than absolutely neutral on the issue of how we subjectively allocate human resources.

    • by Sockatume (732728) on Monday March 03, 2014 @12:47PM (#46388107)

      I think that says more about your misconceptions regarding "check your privilege": the idea is that you become aware of your own observer biases and account for them. It's an idea that's practically created for scientists.

      • "Controlling for observer biases" is a perfectly adequate, accepted, and well recognised way of putting it.

        I'm extremely wary of any politicisation of science (and like it or not "check your privilege" is a very political phrase, being used not for a normalisation of perspective but rather to infer a hierarchy of social advantages which may or may not have any grounding in reality) not least due to the real horrors of politicised science brought to us by the 19th and early 20th century, many of which still

  • by IgnorantMotherFucker (3394481) on Monday March 03, 2014 @10:02AM (#46387097) Homepage

    At first I understood quantum mechanics well enough to get good grades on my problem sets and exams, but I regarded it as delusional because I was heavily into the deterministic Newtonian idea of The Clockwork Universe.

    He was able to give me a deep insight into QM without ever once doing a derivation or even simple arithmetic. For the most part it was purely conceptual discussions of the two-slit experiment.

    What convinced me of quantum indeterminism in the end was Feynman pointing out that the two-slit also works for electrons, not just photons, and that one can use Shot Noise to determine when individual electrons are leaving the hot wire filament used to produce them.

    Even if you send over just one electron at a time, you still get the rippled interference pattern at the detector.

    It turns out that an antiparticle going back in time is exactly the same as a regular particle going forward in time. Just by watching an individual particle, or only a few of them, you cannot determine which direction time is going on.

    It's only when you have enough particles for their measure of entropy to make sense that you can determine which direction time is going in. Entropy ALWAYS increases with time, so if you watch a system of particles, and their entropy is steadily decreasing, they are going backwards.

    I've never heard anyone mention it, but what about smaller systems of particles, where entropy can be measured, but whose entropy fluctuates? Does time go back and forth? I don't know.

    "MAYBE THERE'S JUST ONE ELECTRON!" Feynman once shouted.

    We don't think that's the case - that just one electron goes from the beginning of the Universe to the end, then returns as a positron - because if there were significant amounts of antimatter in the Universe, we would expect there to be lots of 0.511 MeV gamma rays in the cosmic radiation but there is not.

    I am STILL stymied by a question he asked once:

    "Why does a mirror reverse left-and-right but not up-and-down?"

    • by Artifakt (700173) on Monday March 03, 2014 @10:13AM (#46387143)

      Here's a nice video of Dr. Feynman explaining why a mirror works the eay it does - be thou unstymied!

      https://www.youtube.com/watch?... [youtube.com]

    • by wonkey_monkey (2592601) on Monday March 03, 2014 @10:16AM (#46387157) Homepage

      t turns out that an antiparticle going back in time is exactly the same as a regular particle going forward in time.

      I thought determining the truth of that is what this experiment is all about.

      I am STILL stymied by a question he asked once:

      "Why does a mirror reverse left-and-right but not up-and-down?"

      It doesn't. It reverses back-and-front.

      Hold up a print-out of writing on paper you can see through, so that you can read it. Do so with a mirror beyond the paper, and you'll be able to read the writing (through the back of the paper) just fine.

    • Re: (Score:2, Insightful)

      by Culture20 (968837)

      I am STILL stymied by a question he asked once:

      "Why does a mirror reverse left-and-right but not up-and-down?"

      Turn your head 90 degrees so that one eye is higher than the other. Ta Da, it now "reverses up and down."

    • by UnknownSoldier (67820) on Monday March 03, 2014 @10:54AM (#46387397)

      > Does time go back and forth? I don't know.

      Or it could be both :-)

      The classic fallacy of Scientists is duality. Matter behaving as _both_ a wave AND particle is the best proof that:

          One truth does not negate another truth

      But to answer your question, Time is multi-dimensional. It depends on which level you are talking about ...

      From our human, biological perspective / perception time is linear (male) (to prevent insanity.)
      The higher reality is that time flows in all directions (female) (non-linear) BUT one hasn't _experienced_ it all yet.

      The Buddhists would say "There is only Now; the past, present and future are all Allusions" and they would partially be correct.

      > "MAYBE THERE'S JUST ONE ELECTRON!" Feynman once shouted.

      Indeed that is one possibility. That would explain the "Spooky Action From a Distance". It is the _same_ photon, just appearing in different phases at a different time/space.

      That's the greatest thing about Feynman. He always kept an open mind. He was never a pseudo-skeptic. If he didn't know, he was motivated to suspend judgement until he knew more.

      Modern science has become "Cargo Cult" thinking.

      > because if there were significant amounts of antimatter in the Universe, we would expect there to be lots of 0.511 MeV gamma rays in the cosmic radiation but there is not.

      First, the problem is we don't _know_ how much antimatter there is. We are making assumptions about 99.99999% of the universe based on less then %0.0000001 of what we can directly measure.

      Second, how do you reckon that?

      --
      The question is not "Does extraterrestrial life exist?" but
      "Why the hell do we look so similar??"
      News in 2024.

      • by PvtVoid (1252388)

        > Does time go back and forth? I don't know.

        Or it could be both :-)

        The classic fallacy of Scientists is duality. Matter behaving as _both_ a wave AND particle is the best proof that:

        One truth does not negate another truth

        But to answer your question, Time is multi-dimensional. It depends on which level you are talking about ...

        From our human, biological perspective / perception time is linear (male) (to prevent insanity.) The higher reality is that time flows in all directions (female) (non-linear) BUT one hasn't _experienced_ it all yet.

        The Buddhists would say "There is only Now; the past, present and future are all Allusions" and they would partially be correct.

        > "MAYBE THERE'S JUST ONE ELECTRON!" Feynman once shouted.

        Indeed that is one possibility. That would explain the "Spooky Action From a Distance". It is the _same_ photon, just appearing in different phases at a different time/space.

        That's the greatest thing about Feynman. He always kept an open mind. He was never a pseudo-skeptic. If he didn't know, he was motivated to suspend judgement until he knew more.

        Modern science has become "Cargo Cult" thinking.

        > because if there were significant amounts of antimatter in the Universe, we would expect there to be lots of 0.511 MeV gamma rays in the cosmic radiation but there is not.

        First, the problem is we don't _know_ how much antimatter there is. We are making assumptions about 99.99999% of the universe based on less then %0.0000001 of what we can directly measure.

        Second, how do you reckon that?

        -- The question is not "Does extraterrestrial life exist?" but "Why the hell do we look so similar??" News in 2024.

        Are you the Time Cube [timecube.com] guy?

        • Sorry to disappoint, but no. He used to post on /. but I haven't seen him in years. Why, do you miss him? ;-)

          The point though is that never hurts to keep an open mind. At one time you would be thought crazy if:

          * one suggested light is solely matter (shown incomplete with Double Slit Experiment)
          * one suggested the universe is non-deterministic (shown incomplete with Quantum Mechanics)
          * one thought they could infinitely divide space or time (shown incomplete with Planck Length and Planck Time proving the u

    • It does neither. Which dimension reversed is left as an exercise to the reader. Hint: it's not time.

    • by u38cg (607297)
      Reflection is not rotation which is what you are doing when you "reverse" left and right. They are not reversed, they are still in the same places.
    • Even if you send over just one rock at a time, you still get the rippled interference pattern in the pond.

      Sounds like an ether to me...
    • I am STILL stymied by a question he asked once:

      "Why does a mirror reverse left-and-right but not up-and-down?"

      because our eyes are left and right, not up and down. i figured that out in 2nd grade.

      • by dylan_- (1661)

        I'm afraid you've been wrong since 2nd grade then.

        The mirror is actually misleading. Here's an alternative question:

        Why, when you're facing another person, are your left and right reversed, but your up and down the same?

        Bonus question: It's easy to describe what up and down are (down is closer to the Earth, up is further away). How would you describe left and right?

    • by ppanon (16583)
      Seriously, you expect us to believe that you got tutored by Feynman in quantum mechanics for the double slit experiment, but that you can't figure out that the orientation of mirror reversal is due to the horizontal alignment of binocular vision (a trivial optics problem)? Bad troll.
      • by Anonymous Coward

        Given that binocular vision has nothing to do with that problem that's an odd way to respond to someone.

      • by PvtVoid (1252388)

        Seriously, you expect us to believe that you got tutored by Feynman in quantum mechanics for the double slit experiment, but that you can't figure out that the orientation of mirror reversal is due to the horizontal alignment of binocular vision (a trivial optics problem)? Bad troll.

        So you think that if you close one eye and hold a book up to a mirror, you'll suddenly be able to read it?

    • by Xerxes314 (585536)

      "MAYBE THERE'S JUST ONE ELECTRON!" Feynman once shouted.

      Actually, that's basically right. Our current understanding (in quantum field theory) is that there's only one electron field, and all electrons and positrons are quantum excitations of that field. It's a bit more complicated, in that there are actually four electron fields, which cover left-handed/right-handed and electron/positron degrees of freedom. But if you think of those four fields as being the "one" electron, the idea works perfectly.

    • by idji (984038)
      Because your eyes are left and right of each other. Tilt your head 90 and try again.
      • by Zalbik (308903)

        Of course! That's must be why mirrors don't reverse anything if you close one eye (or are a cyclops).

        What's really weird is what happens if you have 2 people in the room with a mirror, one with their head tilted and one vertical. If you hold up a piece of paper with letters on it, one sees the letters reversed, and the other not!

        (for our humor-impaired mods, the above is sarcasm).

    • by phorm (591458)

      "Why does a mirror reverse left-and-right but not up-and-down?"

      It doesn't reverse left and right. It reflects.

      The image from the mirror is as it would be from an observer facing you, kinda like the difference between "stage left" and "personal left"

  • What? No dilithium crystal jokes yet?

    I blame it on the redesign.

  • You had me at "antimatter-beam."

  • from TFA:
    "It will not be used as a disintegrating death ray, but to study symmetries and invariants. This is much more interesting..."

    Oh, no its not! :-p

  • by shrikel (535309) <hlagfarj.gmail@com> on Monday March 03, 2014 @12:29PM (#46388001)

    The purpose of the experiment is to test CPT (Charge/Parity/Time) inversion to determine if the universe would look the same if we simultaneously swapped all matter for antimatter, left for right, and backwards in time for forwards in time.

    "As long as no red flags are raised in the experiment, we plan to move forward with the project in November," said top engineer Fedwick McGillicutty. "Our hope is that, by reversing time itself, we can do away with the whole debacle that is 'daylight savings time.'"

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