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

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.

176 of 268 comments (clear)

  1. why time seems to only want to go from past... by Anonymous Coward · · Score: 5, Funny

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

    1. Re:why time seems to only want to go from past... by Big+Hairy+Ian · · Score: 1

      Wait there is a precedent here we all know the space time continuum is largely based on gravity and Newton taught us all about gravity & apples.......

      --

      Build a Man a Fire, and He'll Be Warm for a Day. Set a Man on Fire, and He'll Be Warm for the Rest of His Life.

    2. Re:why time seems to only want to go from past... by Anonymous Coward · · Score: 1

      Back up, not backup. Backup is a noun, like "take this backup to the basement".

    3. Re:why time seems to only want to go from past... by Existential+Wombat · · Score: 1

      You mean, “take this backdown to the basement” surely.

    4. Re:why time seems to only want to go from past... by Daniel+Klugh · · Score: 1

      Back up, not backup. Backup is a noun, like "take this backup to the basement".

      Thank You!

      --
      Daniel Klugh
    5. Re: why time seems to only want to go from past... by antdah · · Score: 1

      Then there is that classic saying about not comparing apples and pear-shaped nuclei.

  2. That's the state of the universe then... by mjm1231 · · Score: 5, Funny

    the whole thing has gone pear-shaped.

    --
    Ideology: A tool used primarily to avoid the bother of thinking.
    1. Re:That's the state of the universe then... by goombah99 · · Score: 2

      the whole thing has gone pear-shaped.

      I prefer the idea that time is suppository shaped.

      --
      Some drink at the fountain of knowledge. Others just gargle.
    2. Re:That's the state of the universe then... by goombah99 · · Score: 5, Funny

      the whole thing has gone pear-shaped.

      I prefer the idea that time is suppository shaped.

      So it's a good thing that time only runs in the forward direction then. (as Cat on Red dwarf found out).

      --
      Some drink at the fountain of knowledge. Others just gargle.
    3. Re:That's the state of the universe then... by goombah99 · · Score: 4, Funny
      --
      Some drink at the fountain of knowledge. Others just gargle.
    4. Re:That's the state of the universe then... by rtb61 · · Score: 3, Interesting

      Pear shaped means time runs neither forwards nor backwards, it has a direction and that is that, it is arbitrary which direction that is, everything is just bound to that direction, well within our space, stranger things happen in infinitely small and infinitely large space and especially beyond where they become the same relative to our scale.

      --
      Chaos - everything, everywhere, everywhen
    5. Re:That's the state of the universe then... by Fire_Wraith · · Score: 1

      All is not lost. Clearly they didn't bother to test if the nuclei remain pear shaped when traveling at 88 mph.

    6. Re:That's the state of the universe then... by Harlequin80 · · Score: 2

      Where the smeg is Nodnol?

    7. Re:That's the state of the universe then... by Anonymous Coward · · Score: 1

      It's about swivels. You only need to change the direction it is pointing and you can go anywhere, anyplace, anytime ;)

    8. Re:That's the state of the universe then... by egilhh · · Score: 2

      Where the smeg is Nodnol?

      In Dnalgne, on a planet called Htrae, of course

    9. Re:That's the state of the universe then... by silentcoder · · Score: 2

      >I prefer the idea that time is suppository shaped.

      Actually... this is more like buttplug shaped.

      --
      Unicode killed the ASCII-art *
    10. Re:That's the state of the universe then... by stealth_finger · · Score: 1

      Bulgaria

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    11. Re: That's the state of the universe then... by JustBoo · · Score: 1

      And that direction, maybe we can use a word to name it. I propose the name "forward". And the opposite, we can call it "backward".

      Ding. Spacey Relativism is not just pointless, it is now directionless.

    12. Re:That's the state of the universe then... by kimvette · · Score: 1

      And, nuclei vibrate.. so the universe is a vibrating buttplug.
      I'm not sure that revelation would get you a Nobel Prize. ;)

      --
      The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
    13. Re:That's the state of the universe then... by GargamelSpaceman · · Score: 1

      Whenever I read physics stuff I feel like I'm the last segment of the Human Centipede of knowledge. Pear shaped, meaning a nucleus points in a direction meaning things aren't symmetrical.. How is that again? What does this have to do with time? They just say it does, and maybe they know why but it's meaningless to me.

      --
      ...
    14. Re:That's the state of the universe then... by budgenator · · Score: 1

      And, nuclei vibrate.. so the universe is a vibrating buttplug.
      I'm not sure that revelation would get you a Nobel Prize. ;)

      It might if there was a practical application, what could one do with a vibrating universal buttplug?

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    15. Re:That's the state of the universe then... by Dishevel · · Score: 1

      Forward is fairly well defined. Continuing in the direction of travel or moving in the direction of your current facing is "Forward". Backwards is the opposite of that.

      --
      Why is it so hard to only have politicians for a few years, then have them go away?
    16. Re:That's the state of the universe then... by neoRUR · · Score: 1

      If its an arbitrary direction, then is it not conceivable that that direction could loop back onto itself?

    17. Re:That's the state of the universe then... by rtb61 · · Score: 1

      You have got to think of the greater universe. With infinite small particles on one side, which inherently must be superconducting, relative to us and infinite large particles on the other side and relative to those particles we are superconducting. So the direction is not set by our relative scale but by that infinitely large scale. We follow a direction set and that direction does change and can have extremely calamitous results, however that change occurs infinitely slowly. Interestingly enough, distortions within that infinitely large and infinitely slow scale should allow stasis fields. Just like the other direction, infinitely small and infinitely fast, allows you to do strange things with time but only relative to those particles themselves and probably allows us to manipulate the field reactions with our scale (not so much shifting our scale particles but shifting information via those infinitely small particle range).

      --
      Chaos - everything, everywhere, everywhen
    18. Re:That's the state of the universe then... by rtb61 · · Score: 1

      Quite simply if you feel that way, if it is meaningless, you are rushing your effort. Don't bother trying to understand it immediately, mull over, shift it about, twist it, add other thoughts to it, take your time and enjoy the thoughts, of trying to get your mind into the shape required to accommodate the information. There is no exam, enjoy your time, sitting and thinking, walking and thinking, eating and thinking and lying in bed awake late into the night thinking, if you just knew, where would the fun be in discovery. Find it uncomfortable, just park it and focus on other interesting stuff you can add back to it.

      --
      Chaos - everything, everywhere, everywhen
    19. Re:That's the state of the universe then... by stealth_finger · · Score: 1

      Young marklar, your marklars are wise and true.

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    20. Re: That's the state of the universe then... by GargamelSpaceman · · Score: 1

      Pretty much this. Why does a nucleus being pear shaped have far reaching implications about time but a pear being pear shaped not? Maybe there is a reason, but not in TFA. Maybe they are saying they point a certain way like a compass needle? Strange.

      --
      ...
    21. Re:That's the state of the universe then... by doccus · · Score: 1

      I think previously time always went in every direction all at once. Pretty sure that was already proven, too, by Timothy Leary... Oh,, with Owsley's help :-)
        I'm a little unclear how a pear shaped nucleus (or a spherical one, for that matter) coexists with a flat universe, however...

    22. Re:That's the state of the universe then... by Maritz · · Score: 1

      Yeah. Anything that doesn't have a net force acting on it to create an acceleration is just going 'forwards'. I believe that's where the idea of the geodesic comes in.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
    23. Re: That's the state of the universe then... by Maritz · · Score: 1

      A pear is pear-shaped because of evolution and later artificial selection. It's a huge arrangement of atoms and could therefore be pretty much any shape.

      An atom should be getting its shape directly from the fundamental laws of physics. You would expect all atoms with same numbers of protons/neutrons to be the same shape. There is no wiggle room for historical contingency.

      The pear is an asymmetric shape, you would generally expect fundamental (or near-fundamental) objects to be spatially symmetrical, but apparently not.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
    24. Re:That's the state of the universe then... by Maritz · · Score: 1

      It's the only place you've any chance of catching a show by the Incredible Reverse Brothers.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
    25. Re: That's the state of the universe then... by TopherC · · Score: 1

      I am not a nuclear physicist, but I still don't get the distinction here. Nuclei are formed through processes that are full of asymmetries. For example, two nuclei collide, or a neutron is captured, or whatever. Is there some theory that asserts that nuclei must obey certain symmetries regardless of the constituent parts? These are unstable nuclei to be sure. Maybe they are an excited state that decays via gammas to a more symmetric one (which could be even less stable)? I'm not sold here but hoped some slashdotter could help illuminate this better.

      Take snowflakes for example. They aren't all perfectly symmetric even though the bonds have a certain symmetry. The history of their formation manifests in the shape of the snowflake and causes deviations from the prevailing symmetry.

    26. Re: That's the state of the universe then... by TopherC · · Score: 1

      I think I can partially answer my own question. The protons and neutrons in the nucleus can be described as being in a sort of quantum fluid with essentially no viscosity. So Although in some sense the nucleus is hard and almost incompressible, it's more like a superfluid than it is like a crystal. So I'm guessing that the "pear" shape is an unexpected nucleon wave function. Again I'm no nuclear physicist but maybe the situation is something a little bit like that?

  3. What is this I don't even by Pfhorrest · · Score: 5, Interesting

    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?

    --
    -Forrest Cameranesi, Geek of all Trades
    "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    1. Re:What is this I don't even by lgw · · Score: 4, Insightful

      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?

      --
      Socialism: a lie told by totalitarians and believed by fools.
    2. Re: What is this I don't even by Anonymous Coward · · Score: 2, Interesting

      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.

    3. Re: What is this I don't even by Pfhorrest · · Score: 1

      The process of a brain (or any other mechanism) recording information about its environment decreases the entropy of the brain (or other mechanism), thus necessitating an even greater increase in entropy in the environment, so that the second law is obeyed for the total brain-environment system.

      So for any system where some part of the system is recording information about the rest of the system, the total entropy of that system will have to go up, modulo any exchange of entropy with something outside the system. So for the universe as a whole, unless it has an extra-universal entropy sink, any time any information about the universe is recorded in some part of the universe, the total entropy of the universe has to go up (even though the entropy of that part with the record goes down).

      In fact even if the universe had a magical extra-universal entropy sink that took away just enough entropy to keep universal entropy constant (rather than increasing), a brain or any other recording mechanism is still pumping entropy out of itself into its environment (in the process of lowering its own internal entropy, to make the recording), so even if universal entropy didn't go up, any ongoing record would show an external world (i.e. the environment outside of brain or other recording mechanism) always increasing in entropy.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    4. Re:What is this I don't even by Pfhorrest · · Score: 1

      The process of a brain (or any other mechanism) recording information about its environment decreases the entropy of the brain (or other mechanism), thus necessitating an even greater increase in entropy in the environment, so that the second law is obeyed for the total brain-environment system.

      So for any system where some part of the system is recording information about the rest of the system, the total entropy of that system will have to go up, modulo any exchange of entropy with something outside the system. So for the universe as a whole, unless it has an extra-universal entropy sink, any time any information about the universe is recorded in some part of the universe, the total entropy of the universe has to go up (even though the entropy of that part with the record goes down).

      In fact even if the universe had a magical extra-universal entropy sink that took away just enough entropy to keep universal entropy constant (rather than increasing), a brain or any other recording mechanism is still pumping entropy out of itself into its environment (in the process of lowering its own internal entropy, to make the recording), so even if universal entropy didn't go up, any ongoing record would show an external world (i.e. the environment outside of the brain or other recording mechanism) always increasing in entropy.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    5. Re:What is this I don't even by Anonymous Coward · · Score: 1

      It is the deletion of information in memory that inreases entropy.

      That is why maxwell's daemon can't work.

      That deletion of information in the sense that would be of use for disproving Maxwell's demon would have an impact on entropy is an idea that was invented as a suggestion to protect the second law of thermodynamics. If you reverse the statement the way you did you end up with circle reasoning.

      Now, Maxwell's demon is a bit more problematic than that and can not be sufficiently disproved by just inventing theories about information cost.
      If you for example allow the particles to move in a deterministic fashion then the hatch can move in a fixed pattern and still create energy so you also need non-determinism to disprove the demon. Here it isn't sufficient to just have randomness within an average distribution since the demon doesn't have to block all particles in a single direction. It is sufficient that the average distribution is deterministic.

    6. Re:What is this I don't even by Anonymous Coward · · Score: 1

      And what *is* that direction?

      Because that would seem to be important.

    7. Re: What is this I don't even by Samantha+Wright · · Score: 1

      I don't think it's a particular direction; the point is more that the distortion behaves like a normal physical object in that it can be rotated by someone picking it up and moving it. Some other phenomena like electron clouds only exhibit measurable orientations in the presence of other charged particles.

      --
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    8. Re: What is this I don't even by Samantha+Wright · · Score: 1

      ...Which, no big surprise, suggests these two nuclei could actually be two objects eclipsing each other.

      --
      Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
    9. Re:What is this I don't even by kilfarsnar · · Score: 1

      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.

      --
      "What the American public doesn't know is what makes them the American public." -Ray Zalinsky (Tommy Boy)
    10. Re: What is this I don't even by Plus1Entropy · · Score: 1

      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.

      --
      Only crack the nuts that crack. You don't put the ones that don't crack in the sack.
    11. Re:What is this I don't even by Plus1Entropy · · Score: 1

      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.

      --
      Only crack the nuts that crack. You don't put the ones that don't crack in the sack.
    12. Re:What is this I don't even by Anonymous Coward · · Score: 1

      My best interpretation based on these and other related stories is that the "pointing" is actually literal pointing and is reproducible.

      My guess is actual direction is buried in significant angular error (probably determined after formation of the nuclear pear but before other perturbations cause further rotational / positional movement along with any Heisenberg uncertainty limits on absolute measurements), but the pointing direction is measurable enough to show that all such measured atomic nuclei could be pointing to the same point in space. Based on the theoretical work being used in these studies, the best guess is that is the direction from which we "Big Banged", as that would be what theoretically started time forward. This measured pointing seems to hold for the various labs across the Earth's surface which have measured it and the common point in space also holds regardless of where in Earth's orbit it was when the measurements were taken.

      Restated: All atoms observed to form a pear have the pointy end of the pear point within a 120deg* conical error window to a specific region of space.

      *quantity picked to indicate a large error that was still useful in showing pointing (vs. a 180+ deg error, which would not indicate a direction without tons of data points--and possibly not even then)

    13. Re:What is this I don't even by Will.Woodhull · · Score: 1

      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 different terms.

      I am NOT saying that physics is somehow wrong. It isn't. But physics at all levels, from QM to the pure classical physics of Newton, is built up on abstractions of how we perceive the world around us, and those abstractions by definition are only pieces of reality seen from particular points of view. In other words, and has been said many times before, the observer is an integral part of the event being observed.

      Time is usually best seen as an attribute we bring with us to each and every one of our observations. As such, it belongs more to the psychology side of the psych/physics entanglement than to the physics side.

      --
      Will
    14. Re: What is this I don't even by Pfhorrest · · Score: 1

      I never said that entropy causes memory, I said that the necessity of memory increasing universal entropy means that the states we we remember are always less-entropic ones, and so the universe seems to us to be more entropic in the past (i.e. in the states we can remember) and less entropic in the future (i.e. in our predictions of states that will follow from that trend).

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    15. Re: What is this I don't even by Pfhorrest · · Score: 1

      universe seems to us to be more entropic in the past [...] and less entropic in the future

      whoops, I switched "less" and "more" there for some reason

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    16. Re:What is this I don't even by Pfhorrest · · Score: 1

      Thanks, for some reason I have a bad habit of swapping less/more when discussing entropy. Some part of my mind wants to think of the more-entropic state as "lesser", I guess.

      But entropy very much can be defined without memory. You can be given a random series of bits that mean nothing to you, and mathematically describe how entropic that piece of information is, in absolute terms with no reference to any other benchmark information.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    17. Re:What is this I don't even by budgenator · · Score: 1

      The problem with white holes is that the matter had to come from somewhere and if you smoke just the right amount of pot it makes sense that the matter would come from the black holes.

      Perhaps the hole is only black on the outside if you smoke just the right amount of pot.

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    18. Re:What is this I don't even by lgw · · Score: 1

      You've certainly added a lot to the conversation. Were you motivated by anything other than "virtue signalling" about Trump and the Brexit?

      --
      Socialism: a lie told by totalitarians and believed by fools.
    19. Re:What is this I don't even by budgenator · · Score: 1

      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.

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    20. Re: What is this I don't even by jensend · · Score: 1

      But without any other asymmetries in physical laws, we have every reason to think entropy should increase going backwards in time just as well as forwards.

      Decreases in entropy aren't impossible, they're just vanishingly unlikely. If you have a state with less than maximal entropy, of course you expect its entropy to increase. But because the physical laws are symmetric, if you're treating all volumes of state space equally, you also expect the same thing if you replace t with -t. The most likely way for a low entropy state to arise is as an unlikely random fluctuation from a higher entropy state. A past with lower entropy than the present is just as unlikely as a future with lower entropy than the present.

      So if you define past and future via entropy, any state with less than maximal entropy has no past and both -t and t count as future.

      This doesn't match our way of understanding the macroscopic world. We're much more inclined to believe we had an astoundingly unlikely astoundingly low-entropy initial condition. But from a stat mech point of view, without more of an idea why we should treat volumes of phase space this unequally, this amounts to a deus ex machina. So the arrow of time is still a puzzle and this is part of why people are still looking for hints of time asymmetry.

    21. Re: What is this I don't even by Pfhorrest · · Score: 1

      entropy should increase going backwards in time

      And what exactly would "going backwards in time" here mean? Yeah, if you just reverse the velocity/etc of everything in the universe and then let that play on, you wouldn't expect entropy to decrease, but is that really "going backwards in time"?

      What I'm saying is that our very concept of a directionality of time, the very concepts of "past" and "future", arise from phenomena like memory, and other records in some parts of the universe of those parts' interactions with other parts of the universe; and a projection of the patterns apparent in those records, including our own memories.

      Consider every possible point in the phase space of the universe to be equally real, every configuration the universe could possibly have; all of them co-exist, eternally, "timelessly". Those points in the phase space where there exist objects like brains that have records of other parts of the universe, necessarily have records of the universe as it was (is) in less-entropic states, because the processes involved in forming those records happen along paths from less entropic to more entropic states. So no matter what state of the universe you find yourself existing in, your memories and all the other records of other states of the universe present in that universe will be of less-entropic states. We call that direction in the phase-space, the (less-entropic) configurations of the universe that we have records of in this present configuration of the universe, "the past", and then we project a line from that past direction through the present and on into the other direction in the phase-space and call that "the future".

      Because there are more higher-entropy states than lower-entropy states adjacent to any point in the phase-space, "possible pasts" (paths into less-entropic regions of the phase-space) quickly converge and the past seems certain and concrete; the further into the past you project, the more things had to be a certain way to account for the present state. But conversely, possible futures (paths into more-entropic regions of the phase-space) diverge, and the future seems uncertain, and the further into the future we project the more ways there are for the universe to be that are compatible with the present state.

      Thinking about it this way makes questions like "how did the incredibly unlikely low-entropy conditions at the start of the universe arise?" kind of silly, because we are just projecting back from the present state of the universe into necessarily increasingly less-entropic prior states. Any being finding itself in any possible configuration of the universe would find the records available in that configuration (memories, etc) to be of less-entropic states, and projecting back further and further that way find that their universe seemed to begin in an improbably low-entropy condition. Because past means the direction of lower entropy in the phase space, so of course the further in the past you project, the lower entropy it will have to be, to be compatible with the information present at whatever configuration you find your universe to be in; and the furthest in the past you could possible project would be to the nearest (in the phase-space) entropic minimum, which will appear to you as the beginning of time.

      All that we have access to is the present, and the only records that can be in the present are from lower-entropy states of the universe (because creating those records has to increase entropy), so attempting to extrapolate a past and future from the present will always end up with the most distant past seeming improbably low-entropy.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    22. Re: What is this I don't even by jensend · · Score: 1

      Those points in the phase space where there exist objects like brains that have records of other parts of the universe, necessarily have records of the universe as it was (is) in less-entropic states, because the processes involved in forming those records happen along paths from less entropic to more entropic states.

      No. If you treat all parts of phase space equally, the most likely paths to "brains with memory records" are paths from higher entropy states. Even though memory-filled brains or any other kind of "record" spontaneously appearing from disorder is very unlikely, it is more likely than their emerging from an even lower entropy and thus even less likely state.

      Without other reasons to believe an arrow of time exists - a privileged region of phase space or asymmetric physical laws- the likeliest explanation of whatever "record" that appears to indicate a lower-entropy past is that the records are random fluctuations from higher-entropy states. And there are no reasons why "records" should not equally well actually record "previous" higher-entropy states. The region of phase space where I sit here with a neuron arrangement "remembering" my cold chocolate this morning spontaneously getting hot is just as large as the region where I sit here with neurons that "remember" my hot chocolate getting cold.

    23. Re:What is this I don't even by CrimsonAvenger · · Score: 1

      It's just that the direction is not a "normal" direction like "towards the sun", but along their worldlines.

      So, how, exactly, do we know that the direction in question is "along their worldlines"?

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    24. Re:What is this I don't even by gzuckier · · Score: 1

      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?

      yes and no; given that we don't believe in the deterministic newtonian billiard ball universe any more, there is a random component from our POV in the future that is not in the past. i don''t think we know at this point whether that is real or just our future-blindness. of course, this could all be a reflection of the many worlds type of theories, in that all those random possibilities all do exist in the future and all the random possibilities also exist in the past, and the only variable is which path our consciousness travels along them...

      --
      Star Trek transporters are just 3d printers.
    25. Re:What is this I don't even by gzuckier · · Score: 1

      Needless to say, all that Star Trek crap about time travel through wormholes is just that, crap.

      The entire concept of wormholes comes from gut feeling that things should be symmetric together with misusing the singularity model of black holes. By using the singularity model all the way and not just outside of the event horizon a couple of mathematicians figured that since black holes were a singularity in one direction there should also be white holes that emit matter. The problem with white holes is that the matter had to come from somewhere and if you smoke just the right amount of pot it makes sense that the matter would come from the black holes. Thus the wormhole theory was born.

      Adding time travel to the theory doesn't really make it worse, at least not by much.

      black holes are the recycling bins of the universe. when matter comes out of white holes, it's all festooned with "Environmentally Green" stickers and "manufactured entirely from post-universe recycled material". (just kidding, if there's any doubt)

      --
      Star Trek transporters are just 3d printers.
    26. Re:What is this I don't even by gzuckier · · Score: 1

      Needless to say, all that Star Trek crap about time travel through wormholes is just that, crap.

      The entire concept of wormholes comes from gut feeling that things should be symmetric together with misusing the singularity model of black holes. By using the singularity model all the way and not just outside of the event horizon a couple of mathematicians figured that since black holes were a singularity in one direction there should also be white holes that emit matter. The problem with white holes is that the matter had to come from somewhere and if you smoke just the right amount of pot it makes sense that the matter would come from the black holes. Thus the wormhole theory was born.

      Adding time travel to the theory doesn't really make it worse, at least not by much.

      if you smoke more, you start to wonder if maybe actual worms have time travel built into their actual wormholes and we have no way of knowing. in fact, maybe there is only one worm and it just travels back and forth through time giving the illusion of many worms.

      --
      Star Trek transporters are just 3d printers.
    27. Re:What is this I don't even by PingPongBoy · · Score: 1

      Two ideas

      #1 Suppose time just exists in the mind. There seems to have been a past and there seems to be a now. In this mind there is hope of a future. In this mind there appears to be a world, there appears cause and there appears effect. A part of the universe having existed in the past could be constructed meticulously, for example, a cell phone that I had that died and became disconnected. If I built a functioning copy and turned it on, it would see that a network exists, but it wouldn't let me use it because I stopped paying for it. In a way this phone leaped from the past. If the phone that was working in the past leaped to the now, it would be in the same situation. So this is what we think of time.

      But who can say what time is really like? Suppose that the past and the future always exists in the now. Perhaps, even, each past instant is a static slice of spacetime you can traverse spatially, static in the sense of being stuck at the same time on the clock. But perhaps each past or future instant is not static, i.e., traverse it spatially, yes, but every time you look at the clock at that instant, the clock is different, implying you might not even recognize a clock, and what you found at a particular coordinate does not stay the same even though the time does not change.

      Light that leaves but is not intercepted is an example of something in the universe that does not go back in time.

      #2 Pear shaped or not, what is the shape of the aggregate consisting of these atoms having pear shaped nuclei? On the whole is the entire mass also pear shaped or is it just as well balanced as ever?

      The shape of the nucleus arises from a balance of all the forces. The question is whether asymmetry exists at smaller and more fundamental scales.

      --
      Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
    28. Re:What is this I don't even by peawormsworth · · Score: 1

      Early reports seem to indicate the direction points to Mecca.

  4. Galactic North... by __aaclcg7560 · · Score: 1, 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?

    1. Re:Galactic North... by Anonymous Coward · · Score: 5, Informative

      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.

    2. Re:Galactic North... by XxtraLarGe · · Score: 1

      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!

      --
      Taking guns away from the 99% gives the 1% 100% of the power.
    3. Re:Galactic North... by Tablizer · · Score: 4, Funny

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

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

    4. Re:Galactic North... by sexconker · · Score: 2

      Galaxies have centers, as does the known universe. Space expanding has no impact on this fact. Define the boundaries universe at any single point in time and you can define a center. (or at least the center of a bounding spheroid). That center may change as space boils and expands, but you can travel toward it and as you get closer, recalculate it.

    5. Re:Galactic North... by Pfhorrest · · Score: 2

      The boundaries of the known universe are what they are because of where the rest of universe is relative to us, i.e. we can observe things up to a certain distance in any direction. We will thus always observe ourselves to be the center of the known universe.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    6. Re:Galactic North... by jouassou · · Score: 1

      Contrary to popular belief, the big bang wasn't a conventional explosion that hurled lots of mass into empty space, but rather the creation and expansion of space itself, which diluted the mass and energy of the universe. Discussing where in the universe the big bang happened, is kind of like filling a large balloon with air, and then arguing where on the surface of the balloon it all expanded from.

    7. Re:Galactic North... by cfalcon · · Score: 1

      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 in one direction, and another side in another direction. Given enough time and a strong enough telescope, we could even look at our own butts this way. But we see neither our own butts, nor both sides of crazy distant things. If the universe isn't wrapped around like a pacman game, we probably can discuss the idea of a center by asking "where is the center of density of this thing", if you were to measure it from an outside (the existence of "outside" likely not being relevant). There exists some point where there is roughly the same amount of stuff in every direction, and there exists many points where all or almost all of the mass is mostly in one specific direction.

      The one thing I can say about astronomy versus astrology is that one of them has changed a whole bunch in my lifetime, and has predicted nothing ever, being updated with literally every new instrument or experiment ever invented. Astrology has at least predicted some shit entirely by accident, I assume...

    8. Re:Galactic North... by BlackPignouf · · Score: 1

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

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

    9. Re:Galactic North... by alexhs · · Score: 1

      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-shaped in three dimensions, so that could mean the 4th-dimension "inertia" imbalance has effects in three dimensions, but someone more knowledgeable than me would would have to comment if this makes sense.

      (*) AFAIK, if universe's curvature is positive, it's actually an accurate representation. But the universe's curvature is as close of 0 as we can currently measure.

      --
      I have discovered a truly marvelous proof of killer sig, which this margin is too narrow to contain.
    10. Re:Galactic North... by burtosis · · Score: 1

      You can tell if you are moving with respect to the universe, it is trivially simple to detect redshift/blueshift in the CMB. You are moving toward the blueshift hemisphere and away from the red, CMB measurements had to remove things like our orbit around the galactic center. You may always perceive yourself at the center (I suppose each eye at a slightly different one) but determining if you are moving through space in absolute terms is easy.

    11. Re:Galactic North... by DahGhostfacedFiddlah · · Score: 1

      To me, the most important aspect of aether was is a universal reference frame. Galactic North would certainly imply one.

    12. Re:Galactic North... by TMB · · Score: 1

      ...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 him. And it's not as if the bottom of the tower is expanding into the ground below. It's just that the space between him and the bottom appears to stretch away.

    13. Re:Galactic North... by cfalcon · · Score: 1

      > 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 means you could define a point in the universe (or several) from which ALL the mass would be on one side (within a hemisphere), or a point from which mass is roughly equal on all sides (center of mass)- unless the universe is curved, wraps around, etc. That could all the be the case, but I'm pretty sure we see no evidence of that. Am I incorrect?

    14. Re:Galactic North... by Pfhorrest · · Score: 2

      forget about expansion or relativity or anything like that

      you suddenly pop into existence in the middle of a foggy field

      your KNOWN universe is everything within a certain distance of you; beyond that, it's lost in the fog, and wherever the boundaries of the field may be, if there are any at all, they're lost in the distant fog.

      the part of the field that you know of, that you have any experience of, appears to be centered on you, because the ability to know and experience it is a function of its distance from you.

      if the TOTAL universe is finite, we don't know it, and we have no idea where its boundaries are. but the KNOWN universe, the boundaries of everything we have any information about, are a function of the distance of things from us, and consequently we find ourselves always at the center of that.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    15. Re:Galactic North... by Pfhorrest · · Score: 1

      Sure, but I never said otherwise. I was just disputing sexconcer's notion of finding the "center of the universe", and telling your motion relative to the CMB doesn't help you do anything like that.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    16. Re:Galactic North... by david_thornley · · Score: 1

      "Infinity" is not a known value. If it were known, there would be a limit, and it would be finite. There are things known to be infinite, but that means we can't assign a value saying how many there are.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    17. Re:Galactic North... by budgenator · · Score: 1

      To me, the most important aspect of aether was is a universal reference frame. Galactic North would certainly imply one.

      I'm thinking you meant Universal North rather than Galactic. A blackhole conserves mass, charge and angular momentum, so who knows maybe the Universe does as well and we're all just a blackhole in an unknowable Omniverse and there really is universal north.
      Might be interesting to see if Galactic rotations have a statistical bias.

      --
      Apocalypse Cancelled, Sorry, No Ticket Refunds
    18. Re:Galactic North... by jouassou · · Score: 1

      That means you could define a point in the universe (or several) from which ALL the mass would be on one side (within a hemisphere), or a point from which mass is roughly equal on all sides (center of mass)- unless the universe is curved, wraps around, etc. That could all the be the case, but I'm pretty sure we see no evidence of that. Am I incorrect?

      According to the current cosmological models the universe is either curved or infinite, and both options make it impossible to define a unique center.

    19. Re:Galactic North... by gzuckier · · Score: 1

      That's not true at all. If it were, travel through space would be impossible. You can't postulate that the universe started at a single point in space (or single point of space) and then wave your hands about and say "expansion" to come to the conclusion that all reference frames place the observer at the center of space.

      Spacetime is a physical construct and if it's infinite there is no big bang, no expansion, etc., and it can't be generated as we traverse it. If it's finite, it can be bounded. If it's generated as we traverse it, then at any given point in time it is finite and it can be defined and bounded. It will not change faster than we can traverse it (or walking down to the store would be impossible).

      It is absolutely possible for an observer to take a step back and see a bigger picture, though not the complete picture, and approximate a center based on mass distribution or something similar. Of course everything will be bound by our light cone. But an observer being at the center of their own reference frame does not prevent the observer from analyzing other reference frames.

      it can be finite but unbounded. imagine a 2D universe on the outside of a sphere, for instance. and the center of that universe, is actually outside the universe.

      --
      Star Trek transporters are just 3d printers.
    20. Re:Galactic North... by gzuckier · · Score: 1

      forget about expansion or relativity or anything like that

      you suddenly pop into existence in the middle of a foggy field

      your KNOWN universe is everything within a certain distance of you; beyond that, it's lost in the fog, and wherever the boundaries of the field may be, if there are any at all, they're lost in the distant fog.

      the part of the field that you know of, that you have any experience of, appears to be centered on you, because the ability to know and experience it is a function of its distance from you.

      if the TOTAL universe is finite, we don't know it, and we have no idea where its boundaries are. but the KNOWN universe, the boundaries of everything we have any information about, are a function of the distance of things from us, and consequently we find ourselves always at the center of that.

      that happens to you too, eh? damn Jagermeister.

      --
      Star Trek transporters are just 3d printers.
  5. So do they all point in the same direction? by gestalt_n_pepper · · Score: 1

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

    --
    Please do not read this sig. Thank you.
    1. Re:So do they all point in the same direction? by gzuckier · · Score: 1

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

      then there's this one drunk one pointing the wrong direction at 3 am sunday morning, smashing into all the other ones.

      --
      Star Trek transporters are just 3d printers.
  6. The inevitable simulation reference... by Balthisar · · Score: 3, Funny

    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.

    --
    --Jim (me)
    1. Re:The inevitable simulation reference... by Yvan256 · · Score: 1

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

  7. time's direction by goombah99 · · Score: 3, Interesting

    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.

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:time's direction by Oligonicella · · Score: 1

      '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.

    2. Re:time's direction by glitch! · · Score: 3, Interesting

      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.

      --
      A dingo ate my sig...
    3. Re:time's direction by Megol · · Score: 1

      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.

    4. Re:time's direction by Tablizer · · Score: 1

      So, maybe it's really "spooky distance at an action".

  8. Time Travel is easy.... by johnsmithperson123 · · Score: 1

    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.

    1. Re:Time Travel is easy.... by david_thornley · · Score: 1

      I'm always in my rest frame. It may not be the same frame as it was a microsecond ago, but it's my rest frame now.

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
  9. There goes my retirement by Tablizer · · Score: 2, Funny

    My DeLorean stocks just took a bigger hit than Brexit.

    1. Re:There goes my retirement by Joe_Dragon · · Score: 1

      get it to 88 MPH on I-88 at Mile 88

  10. Re:That's the state of the universe [pear-shaped] by Tablizer · · Score: 5, Funny

    My body certainly has. Maybe the atoms examined simply reached middle-age. Time* to put the universe on a diet of neutrino shakes; but they are so bland and often just pass right through ya.

    * No pun intended

  11. The picture in TFA by GuB-42 · · Score: 1

    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?

  12. Simplest explnation is always true by SuperKendall · · Score: 4, Funny

    Points to direction of next quest.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
    1. Re:Simplest explnation is always true by irrational_design · · Score: 1

      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.

    2. Re:Simplest explnation is always true by SuperKendall · · Score: 1

      My post was in jest but that really does sound like a great idea as the base for a story.

      --
      "There is more worth loving than we have strength to love." - Brian Jay Stanley
    3. Re:Simplest explnation is always true by silentcoder · · Score: 1

      Some of the nicest titties are pearshaped, but I've always been partial to teardrop shaped myself. So tits-up and pearshaped sounds like a pretty good state of affairs to me.

      --
      Unicode killed the ASCII-art *
    4. Re:Simplest explnation is always true by david_thornley · · Score: 1

      Doesn't this mean that particle physicists should every so often run into people with large exclamation points over their heads?

      --
      "When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
    5. Re:Simplest explnation is always true by gzuckier · · Score: 1

      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.

      but Pi being infinitely long, it would contain not only an infinite number of copies of the instructions, it would contain an infinite number of copies of every wrong set of instructions of every type.

      --
      Star Trek transporters are just 3d printers.
    6. Re:Simplest explnation is always true by irrational_design · · Score: 1

      Yeah, I haven't read the book in decades. I don't really remember how the book handles knowing that they are no longer looking at "random" numbers but actual instructions that were placed there somehow.

  13. Maybe... by garompeta · · Score: 1

    Maybe it is a watermark from the company who created OUR simulated unverse lol
    Wouldn't it be hilarious that the real world company was named "Pear", and they watched astonished that their simulated universe spawned a company called Apple.
    They might be wondering if there is a universal constant regarding to intelligence, fruits and technological entrepreneurship.

  14. pear, banana... by theMAGE · · Score: 2

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

    1. Re:pear, banana... by Bob+the+Super+Hamste · · Score: 1

      "Explain again how sheep's bladders may be employed to prevent earthquakes."

      --
      Time to offend someone
    2. Re:pear, banana... by gzuckier · · Score: 1

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

      "people all around the globe know that the earth is really flat"

      --
      Star Trek transporters are just 3d printers.
  15. Time has a direction independent of entropy by Roger+W+Moore · · Score: 5, Informative

    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 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!

    1. Re:Time has a direction independent of entropy by silentcoder · · Score: 4, Interesting

      > so why people keep mixing several theories together, is beyond me

      I can tell you that. It's because the only difference between the written down formula for Shannon Entropy and the written down formula for thermodynamic entropy is a single - sign. Which led people to believe that the one is merely an inversion of the other.
      Unfortunately this is an extremely silly conclusion - because although the formulas look the same on paper, they aren't representing the same things. The symbols re the same - but they are not symbols for the same things.
      The conflation of Shannon entropy with Thermodynamic Entropy is only marginally less silly than somebody arguing that carbon dioxide is 2 Oxygen atoms travelling at light speed because C is also the symbol for the speed of light.

      --
      Unicode killed the ASCII-art *
    2. Re:Time has a direction independent of entropy by cat_jesus · · Score: 1

      Cool. An example of an equivocation fallacy in physics. Generally you see the fallacy of equivocation employed by religious people or people denying science.

    3. Re: Time has a direction independent of entropy by silentcoder · · Score: 1

      To be fair there is an actual correlation between the two since storing information (increasing Shannon entropy) does generally require making something physically more ordered (decreasing thermodynamic entropy) so its not quite as silly as it seems but the relationship is probably far weaker than generally assumed and may not exist at all outside of deliberate actions by technologically advanced and intelligent species like us.
      You cpuld argue that building houses and cities decrease thermodynanic entropy as well but the impact on the entropy of the universe is miniscule.
      We really dont have any evidence that the link between these kinds of entropy exist further than hard disk platters and optical disks. It is useful to imagine it does and apply information theory to our observations of other things but to easily do we tend to jump from "this is a practically useful metaphor" to "this is how the universe actually behaves" without realising what a massive leap that really is.

      --
      Unicode killed the ASCII-art *
    4. Re:Time has a direction independent of entropy by Pfhorrest · · Score: 1

      Model a gas in a simulation, and output all of the momenta of every molecule in that gas. That list of vectors will have a very high Shannon entropy. Now decrease the Shannon entropy of that chunk of information, say setting all the vectors to the same value, the average of them all.

      Now make your model of the gas reflect those changes. Look: all your molecules are comoving now, the temperature of the gas has dropped dramatically (and its overall velocity increased as necessary to conserve energy), and the thermodynamic entropy has gone down just like the Shannon entropy has.

      Temperature is noise. It's a measure of how disordered the motions of the members of an ensemble of molecules are. If you somehow change that ensemble so that the description of those motions has less Shannon entropy, then the ensemble itself has less thermodynamic entropy too.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    5. Re:Time has a direction independent of entropy by Roger+W+Moore · · Score: 1

      Yes, the cited experiments proved CP violation...

      No they proved T violation: go and read the papers I gave the refs for. Babar actually did a more complex measurement which really, unambiguously shows T violation. The CP-LEAR result could be argued to be due to CP violation but only if you assume CPT which, given that all quantum field theory has this baked into it from relativity, is very hard to get away from. However I would argue that the CP-LEAR result is a test of T violation since it looks at the process K0 to K0bar (and reverse) as a function of time whereas CP violation manifests itself in the kaon mass eigenstates and their decays. In a CPT conserving frame work CP and T violation are equivalent but without that the T violation in CP-LEAR could give a different result for kaons than you would expect from CP violation.

    6. Re:Time has a direction independent of entropy by Roger+W+Moore · · Score: 1

      I did not say that we could definitely say which direction is "forward" just that if the direction of time was flipped into reverse from whatever it used to be we would be able to tell because the laws of physics would be ever so slightly different. All that physics says is that the two directions, whatever you call them, are not the same.

    7. Re:Time has a direction independent of entropy by ultranova · · Score: 1

      Now decrease the Shannon entropy of that chunk of information, say setting all the vectors to the same value, the average of them all.

      Now make your model of the gas reflect those changes. Look: all your molecules are comoving now, the temperature of the gas has dropped dramatically (and its overall velocity increased as necessary to conserve energy), and the thermodynamic entropy has gone down just like the Shannon entropy has.

      Um, no. The overall velocity of the gas is the same. Setting all of the velocity vectors to their average conserves momentum but not energy.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    8. Re:Time has a direction independent of entropy by Pfhorrest · · Score: 1

      Right, I was a little sloppy in my thinking/writing, sorry. I was thinking about orienting all of the vectors to the same direction, and forgot to account for the magnitudes of those vectors as well.

      So, in the thought experiment again: take the velocities of all the molecules in a gas, reorient them to a common direction, and average their magnitudes. Momentum and energy are both conserved, the velocity of the ensemble increases and its temperature decreases, and the whole thing is effected via the magical decrease in entropy we imposed (because we are the gods of this simulation and we can just do that): we reduced the Shannon entropy of the description that is the model, and in doing so reduced the thermodynamic entropy of the object of the model.

      --
      -Forrest Cameranesi, Geek of all Trades
      "I am Sam. Sam I am. I do not like trolls, flames, or spam."
    9. Re: Time has a direction independent of entropy by silentcoder · · Score: 1

      Thats why I said its less silly than my extreme example and even in another post called it a very useful metaphor. But it doesnt follow that a useful metaphor for describing something implies the thing is the metaphor. There is no information in particle movement. Only something that looks like information to an information processor. It doesnt have actual meaning.

      --
      Unicode killed the ASCII-art *
    10. Re:Time has a direction independent of entropy by ultranova · · Score: 1

      So, in the thought experiment again: take the velocities of all the molecules in a gas, reorient them to a common direction, and average their magnitudes. Momentum and energy are both conserved,

      No, they are not. You can do simple vector operations component-wise, so orientation was never the issue. The issue is that momentum scales with vector length linearly, while energy scales exponentially. So if two vectors of different lengths are adjusted to - or even towards - their average, momentum is conserved but the longer vector loses more energy than the shorter gains.

      Momentum and energy are both conserved, the velocity of the ensemble increases and its temperature decreases,

      Momentum is obviously not conserved if you rotate velocity vectors relative to each other. Energy is not conserved if you average them, as noted above. So combining the two operations conserves neither.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

  16. No back to the past by hcs_$reboot · · Score: 1, Funny

    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"?

    --
    Slashdot, fix the reply notifications... You won't get away with it...
    1. Re:No back to the past by Synonymous+Homonym · · Score: 1

      Time travel has always been impossible. They just discovered yet another way to prove it.

  17. Prior Art by PopeRatzo · · Score: 2, Insightful

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

    --
    You are welcome on my lawn.
    1. Re:Prior Art by freeze128 · · Score: 1

      Station.

  18. I love when Science invalidates Sci-Fi by chromaexcursion · · Score: 2

    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).

    1. Re:I love when Science invalidates Sci-Fi by Hylandr · · Score: 1

      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.

      --
      ~ People that think they are better than anyone else for any reason are the cause of all the strife in the world.
    2. Re:I love when Science invalidates Sci-Fi by moeinvt · · Score: 1

      "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.

    3. Re:I love when Science invalidates Sci-Fi by painandgreed · · Score: 1

      "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.

      Not really. You always have things like Tippler's "Rotating Cylinders and the Possibility of Global Causality Violation" (Physical Review D 9 (8): 2203–2206. Bibcode:1974PhRvD...9.2203T ) but Hawking has a paper out there saying it's impossible, but Hawking loses bets all the time so there might be another physicist who would disagree with their own paper. Continue till one gets a t-shirt. For other ways, it's probably possible to come up with exotic topologies of Reinmannian space so that the math works out and would probably depend on how the author explained and described the process as much as the actual science behind it.

  19. Re:" laws of physics " by MightyMartian · · Score: 1

    This is science journalism, so that means absurdly hyperbolic articles written by idiots that fancy themselves "science journalists". Generally, they're fucking retards who know nothing about science, but are bound by one rule, sex everything up. Science "journalism" is one of the lowest forms of journalism there is. TMZ has better journalism than science "journalism". I ignore science "journalism", because it's usually worse than wrong.

    --
    The world's burning. Moped Jesus spotted on I50. Details at 11.
  20. Volgon Scientists. by Hylandr · · Score: 2

    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.

    --
    ~ People that think they are better than anyone else for any reason are the cause of all the strife in the world.
    1. Re:Volgon Scientists. by Hylandr · · Score: 1

      Sue me then.

      --
      ~ People that think they are better than anyone else for any reason are the cause of all the strife in the world.
  21. Appalling Explained...but really complicated by Roger+W+Moore · · Score: 5, Informative

    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!

    1. Re:Appalling Explained...but really complicated by Cyberax · · Score: 2

      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 interactions with any reasonable precision.

    2. Re:Appalling Explained...but really complicated by JThundley · · Score: 1

      This all reminds me of what Gavin Wince says. What do you think of him, is he a kook?

    3. Re:Appalling Explained...but really complicated by Roger+W+Moore · · Score: 1

      He is most certainly a kook. The dead giveaway is that he publishes to his own website and YouTube instead of reputable, peer reviewed journals and that he is a philosopher not a scientist.

    4. Re:Appalling Explained...but really complicated by Roger+W+Moore · · Score: 1

      No - its the 'theta term' in the expression, called a Lagrangian (technically a Lagrangian density), which could cause this: see this. The term is allowed by all the physics we know but strangely the value of theta appears to be exactly zero (or at least very small) and nobody knows why. Some theoretical models link this tiny value to a type of Dark Matter called axions and I think that finding a tiny, non-zero value of theta is allowed by these models but you would need to ask a theorist in this area to confirm that.

    5. Re:Appalling Explained...but really complicated by JThundley · · Score: 1

      Thanks for your reply :)

  22. Re:Well by sexconker · · Score: 1

    Backward time travel is impossible because it is inevitable that eventually it is used to prevent the discovery of backward time travel.

  23. fat-bottomed nuclei ... by Anonymous Coward · · Score: 2, Funny

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

    1. Re:fat-bottomed nuclei ... by GungaDan · · Score: 1

      "you make the rockin' world go round."

      No, not 'round, only forward. That's the whole point.

      --
      Eloi are stupid, throw morlocks at them!
  24. As the famous Italian Licio Lucchesi said: by fustakrakich · · Score: 1

    *All the nuclei must point in the same direction!*

    --
    “He’s not deformed, he’s just drunk!”
  25. Re:Space Compass? by Ambient+Sheep · · Score: 1

    That all sounds very E. E. "Doc" Smith. :-)

  26. The second law of thermodynamics ... by Ihlosi · · Score: 1
    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.

    1. Re:The second law of thermodynamics ... by micahraleigh · · Score: 1

      You could say the law of gravity prevents objects from leaving the ground, but it happens.

      Random kinetic energy lends itself to diffusion and dissipation, but, seeing as it is random, there could be periods (likely brief) where a small group of atoms move closer together.

    2. Re:The second law of thermodynamics ... by painandgreed · · Score: 1

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

      Unless they can pull energy out of another universe to make up for it. Laws of thermodynamics only hold for closed systems.

    3. Re:The second law of thermodynamics ... by Ihlosi · · Score: 1
      Laws of thermodynamics only hold for closed systems.

      They always hold when all changes are considered. And if two "universes" can exchange energy in any way, they are not two universes, but one.

    4. Re:The second law of thermodynamics ... by gzuckier · · Score: 1

      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.

      but of course you can decrease entropy locally if you increase it elsewhere more to compensate; this is the principle behind life, for instance. so we just need a big entropy dump.

      --
      Star Trek transporters are just 3d printers.
  27. Someone please explain this by pablo_max · · Score: 1

    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.

    1. Re:Someone please explain this by silentcoder · · Score: 1

      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.

      --
      Unicode killed the ASCII-art *
  28. not the time travel you are thinking of by dsoodak · · Score: 1

    A particle traveling forwards in time is (before this research, anyway) mathematically identical to an anti-particle traveling backwards in the time dimension. Historically, we've assumed that you could reverse all the velocities of the particles in a system and it would behave exactly as if time was going in the opposite direction. Showing that this is no longer strictly true does not necessarily mean that the universe doesn't consist of a 4D chunk of space-time which you could travel though using magical technology and make changes which propagate forward according to rules that are just vague enough to prevent infinite recursion. However, not too many people know how significant an exception to time-symmetry is, so I guess they have to make do with the closest widely understood concept. I wouldn't find this so annoying if it weren't for the fact that there are many fields of science which I don't know enough about to know to what extent they are getting creative with the press releases.

  29. There is no time dimension by little1973 · · Score: 1

    http://phys.org/news/2011-04-s...

    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).

    --
    Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
  30. I'm not a physicits, but... by m.alessandrini · · Score: 1

    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?

    1. Re:I'm not a physicits, but... by cfalcon · · Score: 1

      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 speak Physic any better than me (likely!), just go grab the study from any hub of sci, especially a .bz one...

    2. Re:I'm not a physicits, but... by gzuckier · · Score: 1

      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?

      no, the deal is that each nucleus points in a specific direction, and that's new and interesting. up till now the theory holds that nuclei are symmetrical. they shouldn't have a pointy end and a blunt end.

      --
      Star Trek transporters are just 3d printers.
  31. Wind-vane Theory by 7bit · · Score: 2

    Instead of this being a CPT violation that requires all of physics to be "rewritten" there is another possibility that I hope they will look into.

    Just like a finely balanced wind-vane (weather-vane) that can be moved around by the slightest breeze, might it not be the case that these particular isotopes (proton+neutron combinations) result in a unique very delicately balanced system that becomes "sensitive" to the movement and flow of other smaller matter/energy movements which can thus result in the apparent imbalance in shape?

    For instance; if the nuclei of these isotopes are able to be influenced by the flow of a large enough number of neutrinos (for the sake of an example) traveling with sufficient energy then that could cause a wind-vane effect wherein the nuclei would be deformed in the direction of the neutrino flow, or perhaps the opposite? (btw: If this is the case then we now have the ability to build cheap neutrino detectors, or detectors of whatever is causing this.)

    I sincerely hope that this idea is brought up with the scientists involved with these discoveries so that it can be investigated.

    1. Re:Wind-vane Theory by RockDoctor · · Score: 1

      For instance; if the nuclei of these isotopes are able to be influenced by the flow of a large enough number of neutrinos (for the sake of an example)

      Unless my particle physics is wildly wrong, a neutrino interacting with a hadron (proton or neutron) would result in most cases in changing the proton into a neutron (and an anti-electron) or the neutron into a proton (and an electron). At which point, you're no longer talking about a nucleus of Ra-224 (or the Ba analogue).

      At this size range, interactions are quantized. You can't have an arbitrarily small interaction. The lowest spaced gaps between energy levels in heavy metal nuclei is equivalent to the energy of X-ray photons.

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  32. Ugh... by SkyLeach · · Score: 1

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

    --
    My $0.02 will always be worth more than your â0.02, so :-p
  33. Or Not ! by JimSadler · · Score: 1

    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 me.

  34. Getting the Girl by TheRealHocusLocus · · Score: 2

    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::notmake their stupid mistakes and get the girl, this time. It's all about getting the girl. Modern girls don't want to be part of your strange loops, they prefer to get 'got' the first time around by guys who have just figured out the best way to get ''em.

    Let's move on to the real question: what does this upset to physics imply, if anything,to the possibility of stable fusion containment...? Help, hinder, harness? That's the girl we want to get.

    Finding asymmetric nuclei is like discovering that you can put batteries in a toy you got for Christmas. And it's July. So put 'em in and let's see what this thing really does.

    --
    <blink>down the rabbit hole</blink>
    1. Re:Getting the Girl by Maritz · · Score: 1

      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::notmake their stupid mistakes and get the girl, this time. It's all about getting the girl. Modern girls don't want to be part of your strange loops, they prefer to get 'got' the first time around by guys who have just figured out the best way to get ''em.

      I agree. I wish others found time travel as boring as I do. Travelling to the future is easy (even the distant future). Travelling backwards can't be done, and even if you could, you'd be an idiot if you did. So fuck it.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
  35. Not True by Roger+W+Moore · · Score: 2

    But if laws are not symmetric, then your brain will not work the same. You will un-learn and then un-do the experiments, so you will not be able to reach conclusions.

    You are missing a few important details here. First, as far as we know, this time reversal asymmetry does not apply to the EM force which is how our brains work so they would not be affected. Second the effect is a tiny one only measurable with extremely precise experiments so you would not notice an effect without detailed experiments. Lastly though "unlearning", glasses leaping back onto tables etc will only happen if you rewind time, not just reverse the flow i.e. force everything to return to its precise, previous state rather than reverse time and let the universe evolve naturally under it's physical laws. The two are completely different questions.

  36. Reverse != Rewind by Roger+W+Moore · · Score: 2

    Nothing but you have not reversed time you have rewound time and forced everything to go back into the precise state it was in just before. That is NOT the same as reversing the arrow of time. To reverse time you have to let the universe evolve naturally under its own physical laws just now with time counting down rather than up. Essentially all you do is put a minus sign in front of the time and ask whether everything will happen the same with time now going in reverse...and it will not.

    Rewinding time is completely different because in that case the only physical law is that you must return to the fixed state you were in just prior to this one. This will erase all knowledge of what is now the past (because our current state has no knowledge of the future) and there are no real physical laws because everything is predetermined.

  37. But wait...there's more... by evolutionary · · Score: 1

    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.

    --
    "Imagination is more important than knowledge" - Einstein
    1. Re:But wait...there's more... by gzuckier · · Score: 1

      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.

      and some pundit on Fox News will interview Bill Nye and ask him doesn't this pear shaped nucleus thing disprove AGW.

      --
      Star Trek transporters are just 3d printers.
  38. Re:That's the state of the universe [pear-shaped] by cazzazullu · · Score: 2

    Ba, neutrino shakes. Only three tastes, and you can't even be sure it hasn't changed on your drive home from the store.

    --
    int main(void) {while(1) fork(); return 0;}
  39. Shape Dynamics by hawkfish · · Score: 1

    This all sounds consistent Shape Dynamics. IANAP, but according to Lee Smolin's book Time Reborn, 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.

    --
    You will not drink with us, but you would taste our steel? - Walter Matthau, The Pirates
  40. On a Cob by Lavithas · · Score: 1

    Then maybe, just maybe, there's a possibility that we will find nuclei on a cob.

  41. Re: Time Travel Is easy by Quirkz · · Score: 1

    Okay, I'll teach you how to run through time at 100 metric seconds per metric hour. That better?

  42. Re:That's the state of the universe [pear-shaped] by Coren22 · · Score: 1

    Most people want a six pack, I have the whole keg!

    I worked really hard getting in the shape I am, pear is a shape...

    --
    APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
  43. Oversimplifying by Wolvey · · Score: 1

    Just point the nucleus of Barium-144 in the direction in spacetime you wish to travel.

  44. Pear Shaped? by pebear · · Score: 1

    Must have gotten that way from sitting too long and drinking too much beer...

    --
    Paul E. Bahre
  45. big deal by gzuckier · · Score: 1

    Farmers around Chernobyl discover nuclear pears all the time.

    --
    Star Trek transporters are just 3d printers.
  46. Re:Well by gzuckier · · Score: 1

    Backward time travel is impossible because it is inevitable that eventually it is used to prevent the discovery of backward time travel.

    mod up

    --
    Star Trek transporters are just 3d printers.
  47. Flow? by cwsumner · · Score: 1

    Time does not "flow", it is we who move though it. And there is little evidence that we move together, or even in the same direction ...

  48. The 7 Ways to Time Travel by iq145 · · Score: 1
  49. Getting philosophical by GPS+Pilot · · Score: 1

    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.

    Thank you. All pear-shaped objects, even pears, "literally point towards a direction in space." TFA utterly fails to explain how one can then make the leap to saying this proves "there's a well-defined direction in time and we will always travel from past to present".

    But as an aside, if the arrow of time suddenly did reverse, think how odd that would be to experience. We wouldn't be able to see, because photons would be exiting our pupils instead of entering them; we would literally be "un-seeing" sights and unthinking our thoughts. We would walk backwards into concert halls in order to un-listen to musicians. Our emotional states would be the result of things that haven't happened yet. Educated people would become de-educated. Graves would be un-dug; aborted fetuses would spring back to life, and the arguments about whether it is ethical to abort them would be un-had. The "undo" command on every computer would effectively become a "do" command. Later, those computers' operating systems would be uninstalled, and then they would be un-manufactured.

    When time runs in that direction, everything seems rather pointless, does it not? It seems that there's a good reason time does not run in that direction.

    --
    That that is is that that that that is not is not.