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Physicists Discover Geometry Underlying Particle Physics 600

Posted by Soulskill
from the amplituhedron-is-the-word-of-the-day dept.
New submitter Lee_Dailey sends this news from Quanta Magazine: "Physicists have discovered a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality. 'This is completely new and very much simpler than anything that has been done before,' said Andrew Hodges, a mathematical physicist at Oxford University who has been following the work. The revelation that particle interactions, the most basic events in nature, may be consequences of geometry significantly advances a decades-long effort to reformulate quantum field theory, the body of laws describing elementary particles and their interactions. Interactions that were previously calculated with mathematical formulas thousands of terms long can now be described by computing the volume of the corresponding jewel-like "amplituhedron," which yields an equivalent one-term expression."
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Physicists Discover Geometry Underlying Particle Physics

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  • 42 (Score:5, Funny)

    by syntheticmemory (1232092) on Wednesday September 18, 2013 @02:15PM (#44885971)
    Almost there....
    • Re:42 (Score:5, Insightful)

      by RDW (41497) on Wednesday September 18, 2013 @02:33PM (#44886159)

      "They also claim to have found a "master amplituhedron" with infinitely many faces in infinitely many dimensions which should now be as important as the circle in two dimensions. ;-) Its volume counts the "total amplitude" (?) of all processes; faces of this master jewel harbor the amplitudes for processes with finite collections of particles."

      http://motls.blogspot.co.uk/2013/09/amplituhedron-wonderful-pr-on-new.html [blogspot.co.uk]

      No idea what that means, but doesn't it sound cool?

  • by Anonymous Coward on Wednesday September 18, 2013 @02:20PM (#44886029)

    Is secretly a complex distributed particle physics computation!

  • hmmm.... (Score:4, Interesting)

    by P-niiice (1703362) on Wednesday September 18, 2013 @02:21PM (#44886035)
    Isn't this similar to the geometric structure that the 'surfing physicist' came up with - the one that predicts a bunch of undiscovered particles? Or is this completely different?
    • Re:hmmm.... (Score:5, Informative)

      by quantumghost (1052586) on Wednesday September 18, 2013 @02:26PM (#44886093) Journal
      Had the same thought. His name is Garrett Lisi [ted.com]
      • Re:hmmm.... (Score:5, Informative)

        by AliasMarlowe (1042386) on Wednesday September 18, 2013 @03:10PM (#44886551) Journal

        Lisi's E_8 conjecture [wikipedia.org] is somewhat more complicated than this one. For a start, the geometry of the E_8 group is richer than that of a mere amplituhedron. Others may note that Lisi's conjecture also includes gravitation in its unification, while TFA appears to be only about particle families.

        • Re:hmmm.... (Score:5, Funny)

          by ColdWetDog (752185) on Wednesday September 18, 2013 @03:20PM (#44886683) Homepage

          "mere amplituhedron"?

          Are you allowed to say that?

        • Unified theories are more attractive, but every new way of looking at physics (that accurately models reality) is one more potential avenue of insight into the fundamental nature of our universe. This is definitely an exciting discovery, though I do not share their enthusiasm for boiling all of reality down to particle interactions with geometry, rather than statistics.

          The Copenhagen interpretation of QM is a disgrace, and any self-respecting scientist should be ashamed to support a theory that hides reali

    • This isn't a particle so much as methodology; physicists have discovered that certain particles fit together in a certain way. Apparently before this it was a huge clusterfuck. Its like the mandelbrot set; its not a physical "thing", but its damn useful. To physicists only, I think, but we'll see.
      • Re:hmmm.... (Score:5, Interesting)

        by Dishevel (1105119) on Wednesday September 18, 2013 @03:25PM (#44886755)

        This isn't a particle so much as methodology

        The important bit here is why? Why does this methodology work so well. Is it because that deep down on a very fundamental level this "Geometry" is hard coded in the way the universe works? If so. What does this tell us about how things really work?

        • Re:hmmm.... (Score:5, Interesting)

          by St.Creed (853824) on Wednesday September 18, 2013 @03:55PM (#44887099)

          This isn't a particle so much as methodology

          The important bit here is why? Why does this methodology work so well. Is it because that deep down on a very fundamental level this "Geometry" is hard coded in the way the universe works? If so. What does this tell us about how things really work?

          That's a pretty good question. I've been wondering about that too, given the convergence between our definitions of entropy and Kolmogorov complexity, which describes how much information is encoded in a signal (also tied in with Shannon's law). It hits directly into the heart of the question: what is information and how does it relate to reality? At a basic level, our universe may be comprised of "information", or rather: a signal on top of noise.

          This new discovery seems to suggest that at the most basic level, particles can be described as a mathematical function on top of some sort of "white noise" as well. I wonder how long it will take to converge the two ideas. If ever.

          In any case, exciting times are ahead for so-called computer scientists that deal with things like geometric algorithms. I predict a hot demand for top mathematicians in that field to arise very soon.

          Anyway, exciting times to be a theoretical physicist! Everyone expecting breakthroughs coming from the LHC and the experimental boys and girls, and now suddenly, out of left field the theoretical physicists come back with a big right hook out of nowhere :)

        • this "Geometry" is hard coded in the way the universe works? If so. What does this tell us about how things really work?

          right...good question

          the 'Geometry' to which you refer is an expression of relationships

          it tells us how matter and energy relate...which is how physicists say 'how things really work'

          imagine a simple ratio: x/y

          as x increases, y increases...that can be mapped on a graph...

          now thrown in every fundamental particle relationship we've observed, graph it, and it comes up with this geometric figu

  • d20? (Score:5, Funny)

    by space_jake (687452) on Wednesday September 18, 2013 @02:21PM (#44886037)
    Roll for initiative...
  • so... (Score:4, Funny)

    by BenSchuarmer (922752) on Wednesday September 18, 2013 @02:22PM (#44886061)
    God is playing dice with the universe
  • Hold up. (Score:5, Interesting)

    by girlintraining (1395911) on Wednesday September 18, 2013 @02:25PM (#44886077)

    Guys, we've been down this road about a million times in physics. Just because a mathematical model simplifies certain calculations, does not mean that the actual underlying physical geometry matches the theoretical model. Mathematicians have been adding extra dimensions to equations and finding they simplify things for years. It doesn't mean we live in a 27 dimension manifold. All direct observations to date point to a 3D universe.

    • Re: (Score:3, Insightful)

      by benjfowler (239527)

      To elaborate, models are only as good as their power to explain and predict. So if those models improve (explain/predict more, get simpler) over time, so much the better.

    • Re:Hold up. (Score:5, Interesting)

      by gstoddart (321705) on Wednesday September 18, 2013 @02:30PM (#44886131) Homepage

      It doesn't mean we live in a 27 dimension manifold.

      Doesn't mean we don't. ;-)

      All direct observations to date point to a 3D universe.

      Ummm ... hang on a second. Won't any direct observation we make as 3D critters point to a 3D universe? Isn't that sort of inherent to us being only able to perceive 3D?

      I'm not sure how we'd do any direct observations in any other dimensions. (Honestly, not a flame, I'm genuinely puzzled by how we could see anything else and every now and then something like this hurts my head)

      • Re:Hold up. (Score:4, Funny)

        by Anonymous Coward on Wednesday September 18, 2013 @02:51PM (#44886357)

        I'm not sure how we'd do any direct observations in any other dimensions. (Honestly, not a flame, I'm genuinely puzzled by how we could see anything else and every now and then something like this hurts my head)

        First, we assume a spherical cow, now that we have a more efficient source of steak and cheese, we get to the real work. The real work involves creating an infinitely large perfectly flat mirror. Since we don't know of any way to push or pull something into dimensions that we cannot directly observe, we anchor the infinite mirror to the earth (or a designated extraplanetary observatory) and wait. The odds that a 14-dimensional object/creature/other would not accidentally bump into an infinite functionally 2 dimensional surface approach zero as your timescale expands. Therefore, we just wait until the mirror rotates in a way we cannot intuitively describe and effectively ceases to exist in our 3 dimensional space (or drags the earth with it into some other 3 dimensional subset of realities).

        Unless some of the dimensions are curved, then you need a hypercubic pig.

      • Re: (Score:2, Insightful)

        by Anonymous Coward

        This is basically what particle colliders do. Imagine that We lived in a 2D universe like a sheet of paper. The particle collider smashes atoms and we observe the splash it makes. From the splashes around the collision, we see that things seem to have appeared out of nowhere, but if We assume that there is actually a 3rd dimension, we can perceive that the particles/energy didnt just appear, but traveled on an unseen dimension. That is what a particle collider does, if You can wrap Your head around it,

        • by s.petry (762400)

          From the splashes around the collision, we see that things seem to have appeared out of nowhere, but if We assume that there is actually a 3rd dimension, we can perceive that the particles/energy didnt just appear, but traveled on an unseen dimension. That is what a particle collider does, if You can wrap Your head around it, but in our 4D length/width/height/moment range of observation.

          You could take the more rational approach and believe that we simply lack the technology to detect and measure what really happened. Naw, you would rather claim that the particle visited an invisible magical world! Was it Charon pulling the particle across the river Styx for a visit perhaps?

          Wholly fuck we never left the dark ages did we?

          • by mooingyak (720677)

            You could take the more rational approach and believe that we simply lack the technology to detect and measure what really happened. Naw, you would rather claim that the particle visited an invisible magical world!

            I'm not saying he's necessarily right, but if a particle moves along an unseen dimension, its movements are likely still predictable if you've got the mathematical chops. If you're at a point where you can accurately predict something, that's what I'd call a good start.

            But hey if you'd rather just throw your hands in the air and say fuck it I don't know, go for it.

      • Re:Hold up. (Score:4, Interesting)

        by Anonymous Coward on Wednesday September 18, 2013 @03:11PM (#44886561)

        You know how neutrinos have this tendency to change flavors as they pass through time (i.e. neutrino oscillation)? One nifty way of viewing it is that they're 4D objects simply with a spin in the fourth dimension. If you're into the physics, you'll note the same sort of calculations are used in the Pontecorvo–Maki–Nakagawa–Sakata matrix as are used by game engines when calculating the 2D representations of 3D virtual objects: You just then need to do basic matrix transformations to derive the result.

      • Re:Hold up. (Score:5, Interesting)

        by ubermiester (883599) * on Wednesday September 18, 2013 @04:24PM (#44887477)

        Check out Richard Feynman's lecture regarding space-time and his analogy of bugs on a sphere. If you tell them that the rule for making a square is to go N units in one direction, then turn 90 degrees and repeat until you complete the square, they would find that they cannot actually make a square. This leads them to conclude that there is "something wrong" with their space.

        The point is that while the underlying nature of their universe as a sphere is unavailable to them because they cannot escape it to see the bigger picture, they can still infer that because Euclid's rules of geometry don't work there must be something going on that they can't see. Moreover, they should be able to guess that there is curvature - without knowing for sure - because of exactly how the rules break down.

        This is essentially what people talk about when they refer to the difference between larger objects like clumps of atoms and smaller ones like electrons and quarks. For some reason our 3D (technically it's 4D according to Einstein) universe only behaves "normally" until we start measuring it at a small scale. Then we start seeing where our rules about the behavior of "observable" objects - i.e., the stuff we can perceive with our senses - break down and are replaced by the true nature of the subatomic universe. In other words, when we look at quarks do stuff, we can no longer make the square.

        Constructs like the one described above are the result of us trying to get our little bug heads around the way in which our every day rules break down when really tiny things are involved. It's a way for the bugs to correct Euclid to account for the spherical nature of things.

      • by Dunbal (464142) *
        Considering that we have evolved all these different sensory organs to help us survive, I'm sure that if perceiving a 4th dimension granted any biological advantage at all, we would be able to perceive it. Sorry to be anthropic about it but my field is biology not physics, lol.
    • Re: (Score:3, Insightful)

      by Anonymous Coward

      Just because a mathematical model simplifies certain calculations, does not mean that the actual underlying physical geometry matches the theoretical model.

      That's not really a problem if all you want to do is simplify the mathematics. Besides which, that was pretty much the reason that early astronomers weren't branded as heretics; they just said that a heliocentric model made the calculations easier, and that they weren't suggesting that they reflected reality (although they did).

      All direct observations to date point to a 3D universe.

      Well no shit Sherlock. It's rather hard to observe dimensions that your eyes can't see and your mind can't design instruments to detect. Oh... and, you know, time?

      *sigh* With your t

      • Re:Hold up. (Score:5, Insightful)

        by Your.Master (1088569) on Wednesday September 18, 2013 @03:58PM (#44887133)

        and that they weren't suggesting that they reflected reality (although they did).

        What's interesting there is we say it reflects reality because it makes the calculations easier. Other than the math and mental models being easier to grasp, there really is no good reason to say the earth goes around the sun* rather than the sun going around the Earth. We just all decided that the calculations being easier trumps the very intuitive model that the sun circles the Earth. You can construct a perfectly rational model of the Universe from the non-inertial frame of reference that holds the Earth as stationary. It's just full of epicycles etc..

        It's a fairly rare achievement for mass society to replace the naively simpler model of the stationary Earth.

        *for the sake of argument, lets not get into them both orbiting a common barycentre; the argument extends to that as well anyway.

        • What's interesting there is we say it reflects reality because it makes the calculations easier.

          That really is the most interesting thing in this discussion. Essentially we are making a leap of faith, that simpler models are more likely to be true as long as they continue to support the data and allow us to make predictions. But it is at root an aesthetic judgement: beauty is truth, and truth is beautiful. It is the essence of rationality.

          It's cool to see how Feynman's diagrams may be like the epicycles of the earth-centered view of the universe: they can be made to work as long as you keep refin

    • But we live in a 4D universe, or I do. I dont know about you.

      • Re:Hold up. (Score:5, Funny)

        by GodfatherofSoul (174979) on Wednesday September 18, 2013 @02:49PM (#44886333)

        Wait a second...yeah me to

    • Well, locality violations/exceptions are one thing that we've observed which might be construed as an indicator of additional dimensions, i.e. the events might local on an axis we cant see.

    • Re:Hold up. (Score:5, Interesting)

      by sandytaru (1158959) on Wednesday September 18, 2013 @02:35PM (#44886187) Journal
      It seems like their math is like good code. You can get a program to do the same thing in 10 lines what someone else tried to do in 1,000 lines. They're both describing the same basic function, but one is doing it via a brute force in a roundabout way and the other is doing it much more directly.

      Then again, mathematicians tend to be a bit crazy. I remember reading one bio-mathematics person determining that bees do their little waggle dances in nine dimensions projected onto two, and I thought she was insane.
    • by ultranova (717540)

      Mathematicians have been adding extra dimensions to equations and finding they simplify things for years. It doesn't mean we live in a 27 dimension manifold. All direct observations to date point to a 3D universe.

      What observations would those be? If assuming 27 dimensions gets the same results as assuming 3 dimensions, then you can't tell which one the universe is through observation. And if 27 dimensions is a simpler model, then Occam's razor suggests we should indeed consider our home to be a 27D manifol

    • Correction; 4D, and we have direct observational evidence that the universe is infact a larger reality known as "spacetime".
    • Re:Hold up. (Score:5, Funny)

      by Sponge Bath (413667) on Wednesday September 18, 2013 @03:09PM (#44886539)

      All direct observations to date point to a 3D universe.

      Ignignokt: You and your third dimension.
      Frylock: What about it?
      Ignignokt: Oh, nothing, it's cute. We have five.
      [pause]
      Err: Thousand.
      Ignignokt: Yes, five thousand.
      Err: Don't question it.
      Frylock: Oh, yeah? Well, I only see two.
      Ignignokt: Well, that sounds like a personal problem.

    • Re:Hold up. (Score:5, Insightful)

      by Anubis IV (1279820) on Wednesday September 18, 2013 @03:10PM (#44886547)

      IANAPOM (I am not a physicist or mathematician), but from what I could gather from the article, it sounds like this isn't a new model that approximates the old, more complicated one, but rather a massive simplification of the existing one that produces provably identical results in all cases. To drastically oversimplify using my extremely limited understanding while putting it in terms I can wrap my brain around, it sounds like when you first learn about the arithmetic series in calculus (e.g. the summation of i from 0 to n). At first, the only way you can approach it is by actually adding 0 + 1 + ... + (n-1) + n, but eventually you learn that you can skip that whole process if i starts at 0 and use n*(n+1)/2 to reach the result with far less work, and then you're shown how to derive that formula yourself.

      It sounds like something similar here. They previously had to calculate the results of every single Feynman diagram and then sum them together to reach a final result, which would involve billions upon billions of calculations for even a very simple particle interaction. Now, however, rather than having to calculate all of the component parts and summing them, they've derived a formula that produces the same answers with far less work.

      Again, I may be way off, but that's the takeaway I had from the article.

      • Re:Hold up. (Score:5, Interesting)

        by rasmusbr (2186518) on Wednesday September 18, 2013 @03:36PM (#44886895)

        Feynman diagrams are based on the idea that there is framework of time and space, more specifically basically the same time and space that we perceive in everyday life.

        This new model apparently takes a simpler view of the problem by not caring about time and space. I suppose you could say that time and space could be viewed as emergent properties of this geometric object that they have come up with / discovered.

  • does the simplification that it mentions, mean that simulations will be way faster? does it in any way affect the n-body problem simulations ?
    • My impression after reading the article is that this allows for easier predictions of the outcomes of particle interactions, like you might show with Feynman diagrams [wikipedia.org] (particle decay, collisions that produce different particles, etc). Basically, the kinds of things that we'd study in a particle accelerator (so, quantum interactions, rather than classical ones).
    • by arisvega (1414195)

      does the simplification that it mentions, mean that simulations will be way faster? does it in any way affect the n-body problem simulations ?

      An awesome question. And, basically, an awesome idea. I would think that if you can set up a numeric experiment that virtually represents fundamental particles and their interactions, and you already know more or less the trajectories in some n-dimensional space (through this new discovery), then you can probably greatly optimize your algorithms since you will a priori know whereabouts to look for solutions: you would not need to sweep everything.

      Or, you can accept this manifold as truth, and further constr

  • by Max_W (812974) on Wednesday September 18, 2013 @02:34PM (#44886171)
    I have an impressions that the wall of fundamental laws is reached and further research of particles is useless. This is it. No way further. The impasse.
  • by Anonymous Coward on Wednesday September 18, 2013 @02:37PM (#44886205)

    http://en.wikipedia.org/wiki/Amplituhedron

    Since the N=4 supersymmetric Yang-Mills theory is a toy theory that does not describe the real world, the relevance of this theory to the real world is currently unknown, but it provides promising directions for research into theories about the real world.

  • by meta-monkey (321000) on Wednesday September 18, 2013 @02:38PM (#44886219) Journal

    The whole, "our understanding is a dim view of a more perfect geometry" thing gave me a very Neal Stephenson Anathem shiver.

  • by n1ywb (555767) on Wednesday September 18, 2013 @02:39PM (#44886235) Homepage Journal
    Time is an illusion. Lunchtime doubly so.
  • Oblig (Score:5, Interesting)

    by gmuslera (3436) on Wednesday September 18, 2013 @02:42PM (#44886269) Homepage Journal
    xkcd's Purity [xkcd.com]. In the other hand, can't take out of my head that Kepler [wikipedia.org] originally tried to match that the orbits of the 6 known planets at that time with the shapes of the platonic solids, and this could face the same risk.
  • by FilmedInNoir (1392323) on Wednesday September 18, 2013 @02:42PM (#44886271)
    I know some of you are thinking this, but it's not, ok.
    It's not some complicated mess of geometrical shapes to describe the universe in kaleidoscopic glory as envisioned by a lunatic with a Spirograph.
  • It's a time cube (Score:4, Informative)

    by Russ1642 (1087959) on Wednesday September 18, 2013 @02:44PM (#44886301)

    EARTH HAS 4 CORNER
    SIMULTANEOUS 4-DAY
    TIME CUBE
    WITHIN SINGLE ROTATION.
      4 CORNER DAYS PROVES 1
    DAY 1 GOD IS TAUGHT EVIL.
    IGNORANCE OF TIMECUBE4
    SIMPLE MATH IS RETARDATION
    AND EVIL EDUCATION DAMNATION.
    CUBELESS AMERICANS DESERVE -
    AND SHALL BE EXTERMINATED

  • Just as alchemy eventually led to chemistry the mystics win again. The logic in theology is that God by definition would be the ultimate craftsman. That means no errors and no waste and no undue use of effort or energy.
    So just how God make a creation? Obviously endless universes could be set in motion by a science that resembles computer programs. Yes, humanity is nothing but the gorilla with a sledge hammer playing whack-a-mole on a monitor.

  • by Animats (122034) on Wednesday September 18, 2013 @03:02PM (#44886457) Homepage

    This is either a major breakthrough or utter bullshit. It's too early to tell which. If it's real, it's a Nobel Prize in physics.

    The publisher, the Simmons Foundation, is a project of a rich weirdo from Texas.

  • by kipsate (314423) on Wednesday September 18, 2013 @03:35PM (#44886881)
    One of the things the article says is that space and time may not be fundamental properties of nature, but properties that emerge (i.e., are the result of) a more fundamental reality.

    Warning: IANAP. But with some axioms, it is possible to reach the same conclusion.

    Imagine a simple experiment with an electron source and a detector. An electron is emitted in the direction of a detector. The experiment is set up such that while travelling towards the detector, the electron does not interact. More precisely, in between the emitter and the detector, the electron does not exchange any energy. Then, the electron hits the detector and becomes detected (interaction two).

    Has the electron physically travelled in the space between the electron source and the detector? May it be assumed that in between the interaction with the emitter and its subsequent interaction with the detector the electron is physically present?

    Obviously, it is impossible to establish that the electron is present between the emitter and the detector without actually interacting with the electron. It is therefore herewith observed that any assumptions about physical presence of the electron in between the source and the detector can not be experimentally verified. More generally, it is observed that the assumption of physical presence of any elementary particle in between two interactions can not be falsified.

    Equally impossible to falsify is the assumption that in between the emitter and the detector, the electron in the experiment was not physically present. This assumption implies that (in the reference frame of the observer) the electron disappeared at the emitter and reappeared at the detector, and did not take up any physical space at any time in between. In between interactions, the representation of the electron disappeared and became unobservable. For as far as an observer can tell, the electron disappeared from the universe completely in between interactions.

    Since obviously, properties about the electron are preserved in between interactions, the electron must still somehow being represented – i.e., the representation of the electron has clearly not disappeared from the universe.

    The notion “observable universe” is therefore being introduced to make the distinction between interactions which can be observed, and the herewith theorized part of the universe that is apparently capable of at least holding a representation of an elementary particle and which can not be observed.

    Observable universe: The part of the universe in which an interaction manifests itself.

    Let us formulate the following two axioms:

    Axiom 1: An interaction is instantaneous, i.e., it lasts for an infinitely small amount of time.
    Axiom 2: An elementary particle only exists in the observable universe at the moment of its interaction.

    Notice that axiom 1 and 2 are unfalsifiable. Consider the reverse of axiom 2:

    Reverse of Axiom 2: An elementary particle physically exists in the observable universe in the time that passes (in the reference frame of an observer) between two interactions.

    This axiom is equally unfalsifiable, since physical presence of an elementary particle can only be proven by interacting with it. The reverse of axiom 1, which would postulate that an interaction lasts a non-zero amount of time, is equally unfalsifiable.

    Elementary particles have no internal structure and are considered point particles. In other words, an elementary particle does not take up any physical space. If we assume that everything in the observable universe consists of elementary particles, then it follows that all particles that exist in the universe do not take up any space. The aggregate volume of all elementary particles is zero.

    Combined, axioms 1 and 2 state that in between two interactions, an elementary particle is not present in the observable universe. A particle only manifests itse
  • simply nonsense (Score:5, Informative)

    by Browzer (17971) on Wednesday September 18, 2013 @03:36PM (#44886893)

    The Slashdot headline, not the physics.

    http://www.math.columbia.edu/~woit/wordpress/ [columbia.edu]

  • TL;DR (Score:5, Funny)

    by CanHasDIY (1672858) on Wednesday September 18, 2013 @03:37PM (#44886913) Homepage Journal

    My question is - does this get humanity any closer to the point at which I can build my own interstellar spacecraft? If not... why I should care?

  • Feynman Diagrams (Score:5, Insightful)

    by PPH (736903) on Wednesday September 18, 2013 @03:37PM (#44886915)

    This doesn't necessarily invalidate Feynman's approach. His problem was that he assumed a limitless supply of graduate students to calculate the various reaction path probabilities.

  • by Charliemopps (1157495) on Wednesday September 18, 2013 @03:38PM (#44886921)

    The biggest problem with particle physics is that we call them particles when they clearly are not.

  • by acid_andy (534219) on Wednesday September 18, 2013 @05:50PM (#44888371)

    The amplituhedron, or a similar geometric object, could help by removing two deeply rooted principles of physics: locality and unitarity.

    ...And unitarity holds that the probabilities of all possible outcomes of a quantum mechanical interaction must add up to one.

    I'm probably being very naive attempting to understand this article that has probably already been massively dumbed down, but, how can the probabilities of all possible outcomes of an interaction not add up to one? Surely they add up to one by definition, otherwise they are not probabilities? For example outcome X having a probability of 1/3 means, on average, you can multiply the number of times you observe the interaction by 1/3 and get the expected number of times you would see outcome X. If the probabilities in your statistical trials didn't add up to 1, doesn't that mean adding up the numbers of individual outcomes observed would give a number bigger (or smaller) than the total number of interactions observed? Obviously it cannot mean that, as that fails basic arithmetic.

    I can imagine tossing a fair coin - heads has probability 0.5, tails 0.5, total 1. So now how about a 3 sided coin without unitarity? Let's say the probability of heads is still 0.5, tails 0.5 but it has a third side, bodies that also has probability 0.5 of occurring. That sounds mathematically impossible. It could be a mind-reading coin, where you pick heads and find that then occurs on half your coin tosses. Later you pick tails, and that occurs on half your coin tosses, but when you pick bodies, that also occurs on half of those coin tosses. OK, I give up! Can anyone who really understands unitarity enlighten me please? Is this anything like the uncertainty principle?

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