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Physicists Confirm a Pear-Shaped Nucleus, and It Could Ruin Time Travel Forever (sciencealert.com) 268

An anonymous reader writes from a report via ScienceAlert: Physicists have confirmed the existence of pear-shaped nuclei, which challenges the fundamental theories of physics that explain our Universe. "We've found these nuclei literally point towards a direction in space. This relates to a direction in time, providing there's a well-defined direction in time and we will always travel from past to present," Marcus Scheck from the University of the West of Scotland told Kenneth MacDonald at BBC News. Until recently, it was generally accepted that nuclei of atoms could only be one of three shapes: spherical, discus, or rugby ball. The first discovery of a pear-shaped nucleus was back in 2013, when physicists at CERN discovered isotope Radium-224. Now, that find has been confirmed by a second study, which shows that the nucleus of the isotope Barium-144 is also asymmetrical and pear-shaped. In regard to time travel, Scheck says that this uneven distribution of mass and charge caused Barium-144's nucleus to "point" in a certain direction in spacetime, and this bias could explain why time seems to only want to go from past to present, and not backwards, even if the laws of physics don't care which way it goes.
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Physicists Confirm a Pear-Shaped Nucleus, and It Could Ruin Time Travel Forever

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  • by Anonymous Coward on Monday June 27, 2016 @08:50PM (#52403079)

    Can you backup that statement? Oh wait... never mind.

  • by mjm1231 ( 751545 ) on Monday June 27, 2016 @08:57PM (#52403099)

    the whole thing has gone pear-shaped.

  • by Pfhorrest ( 545131 ) on Monday June 27, 2016 @08:57PM (#52403101) Homepage Journal

    Time only "goes from" the past to the future because we define those terms by the way that time "goes", and time "goes" the way it does, from less-entropic to more-entropic states, because the process of memory formation, like all processes, necessitates an increase in entropy. Time isn't actually "going" anywhere, there are just different possible states of the universe, and the ones we we remember (or are otherwise recorded for us to gather information from) are necessarily more entropic, and we call the states we already remember (or otherwise has record of) "past" and the opposite direction in the configuration space "future".

    What the hell could pear-shaped nuclei possible have to do with any of that?

    • by lgw ( 121541 ) on Monday June 27, 2016 @09:06PM (#52403141) Journal

      What the hell could pear-shaped nuclei possible have to do with any of that?

      TFA adds nothing of value - it's just an unsubstantiated claim. The nuclei point "in a particular direction", whatever that means. If they all point in the same direction that would certainly be interesting, but it's not clear.

      Hopefully will get some better science journalism on this one. Where's the Sixty Symbols video when we need it?

      • by Anonymous Coward

        They seem to claim that lumpy nuclei violate CP Symmetry. If the universe can be asymmetric, then maybe (1) there is more matter than antimatter, and (2) other things like time may be assymetric.

        • Hey Richard Feynman --- yeah I hear you laughing, we've been snookered again. It doesn't sound like a downer at all. If we're capable of perceiving that some of these things aren't just 'are' ... they are 'are' yet they are also 'oriented' ... that means we have been given a Signpost to follow ... and we must follow it.

          Never mind that time travel blather. All fixation on 'practical time travel' in physics is a rollover from science fiction, in which it exists solely for humans to go back in time to fix::no

        • If the universe can be asymmetric

          It is, otherwise stars and galaxies could not form.

          there is more matter than antimatter

          There is, at least as far as we've observed.

          other things like time may be asymmetric

          It is, as far as we've observed it only travels in one direction.

          My understanding is that this is a possible explanation for these observations.

      • If they all point in the same direction that would certainly be interesting, but it's not clear.

        I thought that was the point of the discovery? It's just that the direction is not a "normal" direction like "towards the sun", but along their worldlines. They all point in the same "direction" in the sense that they all point towards (or away) from their future (or past) in spacetime.

        Disclaimer: I may have no idea what I'm talking about.

    • time's direction (Score:4, Interesting)

      by goombah99 ( 560566 ) on Monday June 27, 2016 @09:10PM (#52403159)

      How do we know time doesn't go backward? Maybe it does. We'd never know it if it did. (think about it.)

      Perhaps in fact time goes back and forward all the time. This would be a nifty way to have things like spooky action at a distance. You run time forward till a correlated event happens, then run it backward and imbue the necessary future state. Instant hidden variables that you can't detect.

      it doesn't matter how much time this time reversal takes since, you will never notice it happening.

      • by Roger W Moore ( 538166 ) on Monday June 27, 2016 @09:56PM (#52403339) Journal

        How do we know time doesn't go backward? Maybe it does. We'd never know it if it did. (think about it.)

        Surprising as it seems we would actually know if time reversed because of what seems to be one of the most forgotten results of particle physics: the laws of physics do not work the same if time is reversed due to something called "T-violation": literally time-reversal symmetry violation. This is NOT the same thing as a glass falling off a table will not reassemble itself and flying back onto the same because this is an effect of entropy.

        The first evidence for T-violation came from the CP-LEAR kaon experiment at CERN in 1998 [Phys. Lett. B 444 43 (1998)] and was confirmed in B-decays by Babar [physicsworld.com] in 2012 (and as evidence that this result is always forgotten they forgot about the CP-LEAR measurement in this article!!). These experiments looked at how a particle oscillates back and forth between two possible states. What they found is that a particle in state A will oscillate into state B faster than one in state B will oscillate into state A. Hence the process prefers to go in one direction more than the other even though in this case the two states have identical entropy.

        So if time were reversed you would be able to detect it by doing the same experiment and finding that now the particles would go from B to A faster than from A to B. Incidentally this symmetry is also closely related by special relativity to the symmetry between matter and anti-matter so reversing time would switch our universe into one which prefers anti-matter over matter and we could detect this flip again with particle physics experiments.

        So amazing as it seems we could detect a flip in the direction of time and the article is just plain wrong when it says that the laws of physics don't care which way time goes: they do and we have evidence to show it!

      • 'Perhaps' is great for philosophy. In the real world, you gotta provide some evidence. We have evidence of the directional flow of time. Matches never compose from flame. If you're going to suggest that sometimes they do, you're also suggesting that the entire universe backs up a step in exact simultaneity. I'll have to agree with Occam's Razor on that one.

        • by Megol ( 3135005 )

          Flame doesn't produce matches because of entropy, reversal of time doesn't imply reversal of entropy. Then you construct an argument that you think (but not prove - which is the standard) is complicated and therefore think Occam's razor applies. But the razor is a rule of thumb and also doesn't prove anything.

      • Re:time's direction (Score:4, Interesting)

        by glitch! ( 57276 ) on Monday June 27, 2016 @10:20PM (#52403453)

        Perhaps in fact time goes back and forward all the time. This would be a nifty way to have things like spooky action at a distance. You run time forward till a correlated event happens, then run it backward and imbue the necessary future state. Instant hidden variables that you can't detect.

        Yes. I have long thought that this is a plausible explanation for the two slit photon "problem". We observe the photon moving in "our" time direction, but can not observe the same photon as it travels against our time direction. The photon itself is satisfied in its path, the past and future points agree. Thanks for putting this in easily grokable form.

    • by Roger W Moore ( 538166 ) on Monday June 27, 2016 @10:32PM (#52403495) Journal

      Time only "goes from" the past to the future because we define those terms by the way that time "goes", and time "goes" the way it does, from less-entropic to more-entropic states

      Actually that is not true because of something called T-violation which has been observed in kaon and B-meson oscillations (see my other reply to a post below for details but this is NOT an effect of entropy!).

      What the hell could pear-shaped nuclei possible have to do with any of that?

      This is harder to explain and you are absolutely correct that the article utterly fails to do so! We have three special symmetries in particle physics called C, P and T where T is time-reversal and C and P together, CP, is the symmetry between matter and anti-matter. What relativity tells us is that all three together, CPT, should be a perfect symmetry of nature. This means that CP (the matter-antimatter symmetry) and T (time reversal) are linked because if the T symmetry is violated then the CP symmetry must be violated in exactly the opposite way so that CPT altogether is conserved.

      Now the pear shaped nucleus is interesting because the nucleus is bound together by the strong force and every test so far suggests that the strong force obeys C, P and T separately (and so of course also CPT together). The weird violation of T and CP is only seen in the weak force (which causes nuclear beta decay). Now if a nucleus has a non-symmetric shape it suggests that the strong force also violates P, called parity. If P is conserved then if you flip the direction of the x, y and z axes there is no change. However with a pear-shaped nucleus there would be a change and so parity is said to be violated and this means that CP would also be broken.

      So, if true, this result would be interesting because we have never seen this effect in the strong force despite it being possible to add a term to do this and it has always been a mystery as to why this term appeared to be exactly zero - it is called the "strong CP problem". Since CP is tied to CPT by relativity this means that we would expect time reversal to be broken as well by the strong force. However despite the BBC's best effort to advertize Dr. Who this result says absolutely nothing about whether time travel is possible just that time seems to have a preferred direction...which we have known since 1998 thanks to the CP-LEAR experiment.

      As for the "pointing in the same direction in space" I want to see that written in a journal before I give it any credence. Given there are several errors and mistakes elsewhere in the article I the journalism behind this story is seems appalling and I think they completely misunderstood the explanation given...which as you can see above is not exactly trivial!

      • by Cyberax ( 705495 )
        This is not even a violation of CPT! Or even an indication of a preferred direction. A nucleus is a complex compound object, there can even be meta-stable "nuclear molecules" that are held together by strong force. And nobody is surprised that a water molecule is asymmetric.

        What is surprising, is that these nuclei are relatively stable. It appears something strongly suppresses the most energetically favorable decay. Getting the answer to this is going to be tricky - we can't really model the nuclei intera
    • Time only "goes from" the past to the future because we define those terms by the way that time "goes", and time "goes" the way it does, from less-entropic to more-entropic states, because the process of memory formation, like all processes, necessitates an increase in entropy. Time isn't actually "going" anywhere, there are just different possible states of the universe, and the ones we we remember (or are otherwise recorded for us to gather information from) are necessarily more entropic, and we call the states we already remember (or otherwise has record of) "past" and the opposite direction in the configuration space "future".

      What the hell could pear-shaped nuclei possible have to do with any of that?

      The only time that actually exists is Now; the constantly changing, eternal moment of Now. Now is the only time anything can happen. So everything that ever has happened or ever will happen, happen Now. Past and future are only illusions created by our perception.

    • Right on!

      Time is an attribute of how the human mind/brain perceives the universe. There is no way of untangling the psychology of perception from the study of physics at the quantum level. But there is probably no way of convincing most persons who have invested effort in reading and learning about quantum mechanics that this is so. I understand that the few persons who have invested a LOT of effort into learning physics have an understanding of this entanglement, though they probably describe it in differ

      • Time is an attribute of how the human mind/brain perceives the universe. There is no way of untangling the psychology of perception from the study of physics at the quantum level.

        That's true of all of it, every psychological model of the universe breaks down, everything is just varying mass, velocity and charge. in reality it's all jabberwocky to wrap our minds around to maintain sanity.

  • Galactic North... (Score:2, Interesting)

    I'm not a scientist but this pear-shaped atom probably points back to the origin point of the Big Bang. It might be possible find the precise galactic center from where everything got spewed out into the cosmos?
    • Re:Galactic North... (Score:5, Informative)

      by Anonymous Coward on Monday June 27, 2016 @09:03PM (#52403119)

      Nice thought but no, there is no center as you're thinking, space itself expanded with the big bang so the big bang happened literally everywhere. At least as far as we know.

    • I'm not a scientist but this pear-shaped atom probably points back to the origin point of the Big Bang. It might be possible find the precise galactic center from where everything got spewed out into the cosmos?

      No, they all point toward Brexit, and that's why we can't have nice things, such as time travel!

    • by Tablizer ( 95088 ) on Monday June 27, 2016 @09:25PM (#52403219) Journal

      If they point toward Mecca, I will be fully freaked out.

      And, dammit, I just bought a bunch of Xmas decorations last year.

    • by SuperKendall ( 25149 ) on Monday June 27, 2016 @09:35PM (#52403253)

      Points to direction of next quest.

      • Somebody might be able to write an interesting sci-fi story about that. Sort of along the vein of Contact where the instructions for a ship are encoded into PI.

    • How can something physically point to an abstract like time?
      Like, holy shit guys, this thing is pointing left..that's the past!!! Yeah man, they're all pointing left..whoa!!

      I cannot imagine how the orientation of a physical thing can have any correlation, whatsoever to time. Someone please explain this.

      • Basic relativity. Time and Space are two aspects of the same one thing - spacetime. Nothing has JUST a position and direction in space, it also has a direction in time. In Newtonian physics you have a point in space. In Einsteinian physics you have an event in space time. It's not just a position but also a moment.

    • Comment removed based on user account deletion
      • by cfalcon ( 779563 )

        Right, but I know where the center of a balloon is. And if I'm a two-dimensional creature on the surface, I can make three marks, then move in a direction, and eventually notice that I see them from another direction, and then estimate the distance.

        If the argument is that the universe is the three dimensional equivalent of the balloon (or N dimensional, or whatever), then we'd expect there to be a way to gauge this, by basically looking out and seeing if we can see a really distant anything from one side i

        • by TMB ( 70166 )

          ...and this is why I don't like the balloon analogy -- people point to the way in which the analogy is completely unlike the analogous system, and then assume that there is a comparable property in reality.

          Think of the universe as the dolly zoom in the movie Vertigo. No matter where Jimmy Stewart is, as he climbs up the tower, when he looks down you see the bottom of the tower stretching away from him. There is no real center point -- it's not like the center of expansion suddenly moves up the tower with hi

          • by cfalcon ( 779563 )

            > and then assume that there is a comparable property in reality

            Well, if you are arguing that its an object with a volume curved around a fourth dimension, then it is a natural objection.

            Look, right now, a line from the Earth through the Sun will roughly point at the constellation Gemini. That means that the mass of Gemini and the mass of the sun are, at all points today, on the same side of us. Six months from now, that won't be the case- Gemini will be on one side, and the Sun on the other. That mea

    • probably points back to the origin point of the Big Bang.

      "Probably". I don't think it means what you think it means.

    • by alexhs ( 877055 )

      I don't see the approximation I read in an astronomy book and that I still use, so here it is:

      Think of the universe as an hyper-sphere. Well, this is actually hard, so remove a dimension: we're left with a sphere in space, like a balloon, and that balloon is inflated (*).
      At the time of big-bang, the balloon was a point, and it is expanding.
      To be clear, as we removed a dimension, the universe is the balloon surface, not the volume.

      Pear-shaped I guess would point to center / past, but I guess they mean pear-s

  • 'Cause that would be weird. Cool, but weird.

  • by Balthisar ( 649688 ) on Monday June 27, 2016 @09:04PM (#52403129) Homepage

    It's like the sysops are say, well, they're going to discover they're living in a simulation. Change the parameters so nuclei are pear shaped, and that ought to distract them for a little while.

    • by Yvan256 ( 722131 )

      And by "for a little while" you mean for about one hour, or 3.14159265359 million years in the simulation, right?

  • I do it all the time. Around 1s/s. Now, if you want to travel to the future faster, all you have to do is accelerate.
  • by Tablizer ( 95088 ) on Monday June 27, 2016 @09:12PM (#52403173) Journal

    My DeLorean stocks just took a bigger hit than Brexit.

  • A bit off topic but the picture in TFA representing said nucleus seems to be moving even though it is not, like some kind of optical illusion. Did anyone else noticed this?

  • "And that, my lord, is how we know the Earth to be banana-shaped."

  • Before the new particle, past travel could be not impossible. Now they discovered a new particle that makes it impossible. So when they discover yet another particle in the future that invalidates this no-past one, will we be back to "maybe possible"?
  • Prior Art (Score:3, Insightful)

    by PopeRatzo ( 965947 ) on Monday June 27, 2016 @10:13PM (#52403419) Journal

    I'm pretty sure Bill and Ted's Bogus Journey already ruined time travel forever.

  • by chromaexcursion ( 2047080 ) on Monday June 27, 2016 @10:20PM (#52403457)
    Time travel has been over used and generally poorly done. Hopefully this kills it.
    Several Sci-Fi genre relied on gravity not being bound by the speed of light. LIGO has killed that.
    It will be interesting to see where the hard sci-fi authors go now.

    Oddly enough Edgar Rice Burroughs is still sorta safe, since his Mars is in an alternate reality (other obvious failings aside).
    • by Hylandr ( 813770 )

      Light and Gravity is EMF. Penetrate the EMF and you can go as fast as you want. Same as penetrating air for the 'speed of sound'.

      Humans have to think in the correct paradigm. Patterns have a habit of being repeatable.

    • by moeinvt ( 851793 )

      "It will be interesting to see where the hard sci-fi authors go now."

      Huh? There are differing opinions on what constitutes "hard sci-fi", but I thought that "No time travel" and "No FTL" were generally agreed upon principles for defining the genre.

  • by Hylandr ( 813770 ) on Monday June 27, 2016 @10:28PM (#52403483)

    even if the laws of physics don't care which way it goes.

    Lacking access to a good intergalactic physics lawyer the Human race continues to make it up as they go along.

    Imagine navigating the U.S. Justice system by trial and error the way science has been doing it.

    The Volgons at least had a printed manual, in triplicate, read as poetry by some Volgons in self defense.

  • by Anonymous Coward

    ... you make the rockin' world go round.

  • The second law of thermodynamics forbids travelling backwards in time, as this would decrease the entropy of the universe the traveller observes.

    If someone can circumvent the first or second law of thermodynamics, they can call themselves a deity for all intents and purposes.

  • http://phys.org/news/2011-04-s... [phys.org]

    I think until the majority of scientists do not accept this we won't have a unified theory.

    Even Lee Smolin acknowledges that we have some problem with time (in The Trouble with Physics), but he thinks the problem is that we treat time as a static/frozen thing while he thinks it is a dynamic thing like space itself (eg. the shape of space continuously changes due to matter).

  • Is it that ALL the nuclei in the universe point in the same direction, and never move? I don't think so, so why should they identify a privileged time direction?
    • by cfalcon ( 779563 )

      I don't believe it. The study doesn't call out this statement (what, do they all point to the best stone crabs?), and the line, if quoted correctly, might mean something entirely different (such as the shape being consistently pear-like, or that it maintains a shape relative to something entirely unremarkable). Finding that a bunch of Radium atoms point to to a specific star would be pretty amazing, and look for a kooky youtube about it soon! ...but I doubt it really says anything of the sort. If you spe

  • Yet another article that takes massive liberties with pure speculation and has almost nothing to do with science other than the word scientist.

  • If some particles hint at a direction in time and other particles do not then maybe only certain particles have a direction in time. Perhaps other particles have a bias in other directions. Also it may just be that a time bias exists as a very local condition and implies nothing for the rest of the universe. Somehow my suspicion would be that since we know that we are headed for a certain black hole that a directional bias might just be towards that black hole. But then again it is all well beyond m
  • A few years from now someone will "discover" something that disproves the limitaion of the pear shaped nuclei. The one thing about science, it's never certain, and what we thing is fact today, becomes fiction tomorrow. " Fifteen hundred years ago everybody knew the Earth was the center of the universe. Five hundred years ago, everybody knew the Earth was flat, and fifteen minutes ago, you knew that humans were alone on this planet. Imagine what you'll know tomorrow. " K, Men in Black.
  • This all sounds consistent Shape Dynamics [wikipedia.org]. IANAP, but according to Lee Smolin's book Time Reborn [wikipedia.org], this can lead to a preferred frame of reference, including an actual centre of the universe. It also make time into its own thing, disentangling it from space. Which could ruin time travel forever.

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