Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
Math Science

A New Theory of Everything? 511

goatherder writes "The Telegraph is running a story about a new Unified Theory of Physics. Garrett Lisi has presented a paper called "An Exceptionally Simple Theory of Everything" which unifies the Standard Model with gravity — without using string theory. The trick was to use E8 geometry which you may remember from an earlier Slashdot article. Lisi's theory predicts 20 new particles which he hopes might turn up in the Large Hadron Collider."
This discussion has been archived. No new comments can be posted.

A New Theory of Everything?

Comments Filter:
  • by haluness ( 219661 ) on Thursday November 15, 2007 @08:22PM (#21372499)
    The fact that he's a surfer dude deserves some mention as well - not everyday you see hard core mathematical physics coming from the beach!
    • Re: (Score:2, Funny)

      Strong body, strong mind.

      You can't kick ass if you can't get off yours!
    • by rminsk ( 831757 ) on Thursday November 15, 2007 @08:54PM (#21372811)
      This "surfer dude" resume:

      9/91-5/99 University of California, San Diego
      5/99 Ph.D. in Physics
      G.P.A. - 3.9

      Honors Fellowships - UC Regents fellowship, ARCS Foundation fellowship.

      9/86-6/91 University of California, Los Angeles
      6/91 B.S. in Physics and B.S. in Mathematics
      G.P.A. - 3.9 (4.0 in Physics and 4.0 in Mathematics)
      Academic Honors - Phi Beta Kappa, Sigma Pi Sigma, Golden Key.

      Graduation Honors - College Honors, Highest Honors in Physics, Highest Honors in Mathematics, Summa Cum Laude, Kinsey Prize for The Outstanding Graduating Senior in Physics.
      Not quite your average "surfer dude"
      • Go Clifford Algebra (Score:5, Interesting)

        by Anonymous Coward on Friday November 16, 2007 @12:08AM (#21374419)
        Clifford Algebras, Grassman Algebras, Spacetime Algebra, and Geometric Algebra are a group of mathematics notations that are related to the ones being used here. The notation in use has interesting properties that make it more likely that an equation will be valid in any number of dimensions, embeds the behavior of complex numbers, quaternions, hypercomplex numbers in a purely real system, etc.

        I have read of ideas for unifying physics by using these notations for their superior ability to reason with space. (David Hestenes has good examples.) A good physical theory should be like a consistent programmer's interface. If the "code" continues to become unwieldly over time, then a point will be reached where rewrites must be done in order to eliminate special cases and bring out hidden symmetries.

        This particular paper may end up failing important tests, but it does seem clear that at some point Clifford Algebras will end up being the thing that ended up simplifying physics.
    • by sconeu ( 64226 ) on Thursday November 15, 2007 @08:58PM (#21372843) Homepage Journal
      Guess he's just seriously into Wave Mechanics....
    • by mauthbaux ( 652274 ) on Thursday November 15, 2007 @11:02PM (#21373935) Homepage
      First of all, I think it's amusing that that the first post was modded as "redundant", but on to the topic at hand:

      Biology has at least 1 famous 'Surfer Dude'; Kary Mullis. The guy was granted the Nobel prize for inventing PCR (polymerase chain reaction) which is arguably the most important processe in modern genetics or biotechnology. From what I know of the guy, he's a complete whack-job as well, claiming that hallucinogenic drugs led him to the discovery. He surfs frequently as well. Add in a few alien abduction stories and some other relatively crazy stuff and you get an idea of what he's like. Still, it's hard to argue with a Nobel prize winner.
      • Re: (Score:3, Informative)

        by Dr. Smoove ( 1099425 )
        How is he a complete whackjob for claiming that hallucinogens (I believe it was LSD in his case) led him to the discovery? Alien abduction stories are wackjob material, but if you've ever experienced a hallucinogen, you'd know why this isn't too implausible.
      • Re: (Score:3, Interesting)

        by PopeRatzo ( 965947 ) *
        This very moment I'm on a little vacation on the West Coast near Monterey. I had dinner tonight with a couple of lifelong surfers. Neither of these guys is gonna be doing any kind of physics soon. In fact, I'm not sure either of these dudes, nice guys they may be, could put up much of a fight in a battle of wits with any of the plants in my garden. (on the off-chance that they read this - hey Wayne, yo Rick)

        I'm not sure if they are indicative of the intellectual capacity of surfers, and since I was born
      • by handy_vandal ( 606174 ) on Friday November 16, 2007 @09:57AM (#21377967) Homepage Journal
        Still, it's hard to argue with a Nobel prize winner [acidhead].

        Not hard at all -- ! Goes like this:

        Nobel Prize Winner: "My theory," etc.

        Me: "No way, dude!"

        NPW: "Way!"

        Me: "Nuh-uh!"

        NPW: "Uh-huh!"

        Me: "Umm ... okay."
        [Okay, I was wrong. It wasn't easy, and he won the debate.]

  • by wes33 ( 698200 ) on Thursday November 15, 2007 @08:22PM (#21372505)
    Lubos Motl thinks it's pure bullshit ... so Lisi might well be on to something :)
  • by lobiusmoop ( 305328 ) on Thursday November 15, 2007 @08:26PM (#21372541) Homepage
    that the earth is going to get demolished any minute now.
  • Can someone explain to me what E8 is? The wikipedia article left me with more questions than answers :(
    • by mrbluze ( 1034940 ) on Thursday November 15, 2007 @08:48PM (#21372733) Journal

      Can someone explain to me what E8 is? The wikipedia article left me with more questions than answers :(

      Simply put, it's a complex dimensional algebra with lots of non-trivial, commutative degrees of freedom. It features symmetry groups, conjugation and adjoint representation, and comes with a free manifold which displays automorphism - so it can neatly fit into any space. For a small extra fee, we'll throw in some Vogon Polynomials and a Spin(16) (Z/Z2) which, fundamentally, gets your clothes drier, quicker. The best thing about the E8 is it's R8 Root System(TM), which, with the use of Euclidean Space Vectors is guaranteed(*) to make sure you don't get octonions on your breath. And if you order now, we'll send you a bonus 8x6 photo of Jacques Tits.

      But honestly, I foud the wikipedia article pretty useless too. I'm not nerd enough.

      • by markov_chain ( 202465 ) on Thursday November 15, 2007 @11:41PM (#21374231) Homepage
        Let's also mention some applications of E8. The E8 Lie group has applications in theoretical physics, in particular in string theory and supergravity. The group E8×E8 (the Cartesian product of two copies of E8) serves as the gauge group of one of the two types of heterotic string and is one of two anomaly-free gauge groups that can be coupled to the N = 1 supergravity in 10 dimensions. Clearly, E8 is the U-duality group of supergravity on an eight-torus (in its split form). Also, any fool can see that one way to incorporate the standard model of particle physics into heterotic string theory is the symmetry breaking of E8 to its maximal subalgebra SU(3)×E6.

        (mostly stolen from the Wikipedia article).
    • by iabervon ( 1971 ) on Thursday November 15, 2007 @09:23PM (#21373093) Homepage Journal
      (I am not a particle physicist or a mathematician of the right sort, but I can kind of follow this sort of thing)

      Okay, the context is that you've got particles, and they're fundamentally all the same, but they're "turned" in different ways. Think of a ball with 3-color LEDs inside: you can rotate it around three axes, and move it in three directions, and you can also cycle its color and change its blinking pattern. Particles are like that, except that the topology is weird: it's not back to the same orientation until you turn it around 720 degrees, instead of 360 like normal objects. The "gauge group" is the rules for how you can change things. For example, the total color of the universe is white: if you turn something from red to blue, you have to turn something else from blue to red; but you can also create a pair of a green and a purple (anti-green). They write all these rules up in math, and it's tricky because a lot of the features vary continuously (that is, you can rotate something an arbitrarily small amount). And due to the interaction of the rules for one property with the rules for other properties, there are only certain combinations of properties that you can get. They work out all the combinations that you can have and those are what you see as "different" particles that your experiments show. Of course, we don't know what the rules are, and we're trying to figure that out from what combinations of properties we've seen and which ones we're speculating are impossible. And it's hard and takes a lot of calculation to figure out what a candidate set of rules would even mean as far as results. And people are looking at known results and trying to describe them better than "we've done a billion things, and a billion things happened".

      Now, the math of rules for how things can interact turns out to be sort of limited; there are basically 4 normal cases, which are boring, and then there are a few exceptional cases, which are interesting. Of these, the hardest to prove stuff about is E8, and it's just now becoming clear what combinations it allows. It's like one of those puzzles where you press a corner and lights change, and you have to turn off all the lights, but it's got dozens of corners and dozens of lights and every time you press a corner a bunch of things change at once, and there are different kinds of corners and it also matters exactly what angle you're holding it at, so there are hundreds of things you can say about each move.

      And the mathematicians working on E8 recently said, "well, you can get positions like this and not like that", where "this" and "that" are big complicated lists. And this physicist read that paper and said, "hey, those lists are familiar; I made similar lists of particle interactions". So the proposal is that particles work like E8 in what kind of rules they follow. And it's a really nice theory, because E8 is essentially the most flexible set of rules you can have without it falling apart into just anything being possible (and some rules or properties just not mattering).
    • by ROMRIX ( 912502 ) on Thursday November 15, 2007 @10:28PM (#21373683) Homepage

      Can someone explain to me what E8 is? The wikipedia article left me with more questions than answers :(

      Try to picture a spherically inverted multifaceted poly-dimensional plexoid of random size, add in an elemental variable thermal/mass coefficient linking system based on the gravitational and magnetic field enhanced rate of change fluctuations of sub-atomic particles and it all comes together like butter and honey on toast. Well, butter and honey don't really come together on toast but you get the idea...
  • "It's hard to figure out the secrets of the universe when you're trying to figure out where you and your girlfriend are going to sleep next month."

    I smell an XKCD comic approaching....
  • Huh? (Score:5, Funny)

    by ratguy ( 248395 ) <ryanja@noSPAm.gmail.com> on Thursday November 15, 2007 @08:33PM (#21372611) Homepage
    I think some people have an entirely different definition of 'Simple' than myself.
  • FTFA (Score:4, Funny)

    by aproposofwhat ( 1019098 ) on Thursday November 15, 2007 @08:35PM (#21372625)

    it does not require more than one dimension of time and three of space


    E8 encapsulates the symmetries of a geometric object that is 57-dimensional and is itself is 248-dimensional. Lisi says "I think our universe is this beautiful shape."

    Well, am I alone in thinking that invoking another 244 dimensions is rather excessive?

    Especially when an extension of spinor theory to only 6 dimensions (3 time, 3 space) looks to provide a more elegant explanation?

    Sorry, surfer dude - you fail it!


    • Re:FTFA (Score:5, Informative)

      by Carnildo ( 712617 ) on Thursday November 15, 2007 @09:18PM (#21373029) Homepage Journal
      The algebra is 248-dimensional. The universe is still only 3+1-dimensional.
    • Re:FTFA (Score:5, Informative)

      by Anonymous Coward on Thursday November 15, 2007 @11:49PM (#21374287)
      Warning: grossly inaccurate and oversimplified.

      He's not saying space has 248 dimensions, he's describing the geometry of a polygon. If you read the paper, he's only invoking 3 spatial dimensions and one time dimension to define our universe.

      Let's say you've got a cube, and each corner of the cube represents the properties of a subatomic particle. You can have a total of 8 subatomic particles and you can create a direct line between any point on the cube and any other.

      E8 is a 248-dimensional set of lines connecting the points of a 57-dimensional imaginary object. What he has done is merge the E8 "object" with the various subatomic particles and used the remaining unassigned points to predict the features of those particles we have yet to detect. In essence, he's created a math representation of a periodic table of subatomic particles.

      People with Ph.D's in mathematics aren't expected to understand the theory. People with Ph.D's in particle physics aren't expected to understand the theory.

      Quite frankly, there's a serious audience of around one hundred people on the planet that can actually grasp what he's saying, and they seem to be divided about it and its ramifications.

      ~ J. Barrett
    • by pavon ( 30274 ) on Friday November 16, 2007 @12:08AM (#21374417)
      The 248-dimensions that he is talking about are not like the time-space dimensions, which particles move through. They describe the state of the particle itself - things like spin, charge, etc. The standard model has 6(?) properties. Some of the combinations of these properties are allowed, some are not. E8 is a very generalized mathematical model that has 248-properties, where only some of the combinations are allowed. What Garrett Lisi showed is that the rules that describe the allowed combinations of the 6 properties of the standard model show up in E8, and furthermore, the symmetries of gravity can be described with it as well.

      Now, there are other valid combinations of properties within E8 beyond the ones that represent the particles in the standard model, and these combinations would represent new particles that we have not seen before, if the model is correct.
  • Huh (Score:5, Funny)

    by edwardpickman ( 965122 ) on Thursday November 15, 2007 @08:37PM (#21372647)
    So it's not 42?
  • by Lord Byron II ( 671689 ) on Thursday November 15, 2007 @08:41PM (#21372665)
    A set is a collection of things, such as the integers are a set of numbers.

    A group is a set with an operation (and a couple of extra properties), such as the integers under addition.

    The set of a symmetry group is the set of operations that you can perform to an object and have the object remain unchanged. For example, for an equilateral triangle, rotating it by 120 and 240 degrees leaves you with a triangle. So does flipping it around any of its three axes. Add the identity operation, which leaves the triangle untouched and you have the symmetry set for an equilateral triangle. Add an operation and you have a symmetry group.

    The U(1) group is the group of all unitary, 1-dimensional operations that leave the inner (dot) product invariant.

    The SU(2) group is the group of all unitary, 2-dimensional operations that leave the inner (dot) product invariant and have a determinant of 1.

    The SU(3) group is the group of all unitary, 3-dimensional operations that leave the inner (dot) product invariant and have a determinant of 1.

    The Standard Model obeys the symmetry found by combining the three above groups: SU(3)xSU(2)xU(1).

    E8 is another group with some special properties. The author of the paper is claiming that E8 contains the Standard Model (SU(3)xSU(2)xU(1)), plus the symmetries belonging to gravity.

  • by Ghoser777 ( 113623 ) <fahrenba AT mac DOT com> on Thursday November 15, 2007 @08:41PM (#21372669) Homepage
    http://aimath.org/E8/e8.html [aimath.org]

    I found this site easier to understand than the wikipedia link. I warned my trig students about higher dimensions - wait till I tell them about 8-d vectors, they'll love it!
  • PDF (Score:5, Informative)

    by bill_mcgonigle ( 4333 ) * on Thursday November 15, 2007 @08:44PM (#21372691) Homepage Journal
    Really that's all I wanted [arxiv.org] (complete with useless filename and all - 'An Exceptionally Simple Theory of Everything.pdf' - copy/paste)

    here's the abstract for those wondering if they should download it:

    Abstract: All fields of the standard model and gravity are unified as an E8 principal bundle
    connection. A non-compact real form of the E8 Lie algebra has G2 and F4 subalgebras which
    break down to strong su(3), electroweak su(2) x u(1), gravitational so(3,1), the frame-Higgs,
    and three generations of fermions related by triality. The interactions and dynamics of these
    1-form and Grassmann valued parts of an E8 superconnection are described by the curvature
    and action over a four dimensional base manifold.

    Although it is chock full of pretty pictures as well. If he's right, somebody is going to do a story about how the Star of David came to be important (Ezekiel's Wheel?) and want to talk to those soldiers who saw the ship in the woods in Britain that was decorated with a complex pattern with triangles in the middle.

    OK, enough mindless rambling...

  • by Dr. Eggman ( 932300 ) on Thursday November 15, 2007 @08:47PM (#21372709)

    Underlying any symmetrical object, such as a sphere, is a Lie group. Balls, cylinders or cones are familiar examples of symmetric three-dimensional objects. Today's feat rests on the drive by mathematicians to study symmetries in higher dimensions. E8 is the symmetries of a geometric object that is 57-dimensional. E8 itself is 248-dimensional.
    Ha! Take that, 11-dimensional Supergravity SuperString M-Theory!
  • by MichaelCrawford ( 610140 ) on Thursday November 15, 2007 @08:51PM (#21372773) Homepage Journal
    ... by discovering the previously-unpredicted particles that his paper predicts, especially of the properties of the new particles match the predictions, then there is no doubt whatsoever that he'll win the Nobel Prize in Physics.

    Back in the day, I thought I might win the Nobel when I grew up. But life intervened; as of this month I have twenty years as a software engineer. I'm sick to death of it. But I'm not going back to Physics - download the tracks in my sig, and you can help me go back to school to study musical composition.

  • by Sarusa ( 104047 ) on Thursday November 15, 2007 @08:58PM (#21372839)
    Please see what a real physicist thinks of this. There's always a chance that he's stumbled onto something awesome of course, but odds are low. Basically he takes some stuff that looks cool and extracts physics from it in various ways.

    http://motls.blogspot.com/2007/11/exceptionally-simple-theory-of.html [blogspot.com]

    'That's pretty cute! :-) The author is not constrained by any old "conventions" and simply adds Grassmann fields together with ordinary numbers i.e. bosons with fermions, one-forms with spinors and scalars. He is just so skillful that he can add up not only apples and oranges but also fields of all kinds you could ever think of. Every high school senior excited about physics should be able to see that the paper is just a long sequence of childish misunderstandings.'
    • Lubos, on Bee's blog has shown himself to be nothing but an clown. He argues as if he's on the SA forums. When he did attempt to make a point he was quickly made to look like an asshat.

      Judging by the comments from others there, he certainly intelligent, but close minded, immature, and prone to lapses in judgment.
      • Re: (Score:3, Funny)

        by ColdWetDog ( 752185 )

        Also, everyone knows that the fermions arise as chiral multiplets and not vector multiplets: they are simply not and cannot be a part of the gauge bundle.

        Now I feel really bad. I didn't know that.

    • by BoChen456 ( 1099463 ) on Thursday November 15, 2007 @09:38PM (#21373239)

      Thats what unifying physics is all about. Coming up with one theory to explain everything that used to take multiple, completely unrelated theories to explain

      By your analogy, he is showing that apples and oranges are really just different types of fruits.

      The best example I can think of is Maxwell's electro-magnetism equations. It might seem obvious today, but it was an amazing breakthrough to realise that electrical fields, currents and magnetism were really just two sides of the same coin. Most lay people of that time must have thought it was a childish misunderstanding to relate lightning and what makes a compass work

      I can't speak for whether the theory is flawed or not, but I think you're a little too quick to dismiss it based on high school seniors knowledge.

      • by epine ( 68316 ) on Friday November 16, 2007 @01:40AM (#21375137)
        Apples and oranges could equally well have described matter and energy prior to special relativity. How could Lubos be so clueless as not to recognize that many insights in physics arose precisely because someone dared to add apples to oranges? Lubos has an interesting psychological configuration. He would be an ideal subject in an fMRI imaging protocol on the pathological constriction of rational thought. I'd love to see how his brain glucose dances while I recited out loud the most recent Peter Woit blog post. I suspect his amygdala would be more fired up than the tympanist at an indoor performance of the 1812 Overture.

        Lubos should at least feel compelled to explain why the apples of adding fermions to bosons is completely unlike the oranges of adding matter to energy, but he's always lacked that layer of subtly in his expository style.

        In more general terms, Peter Woit also suffers some misconceptions concerning the evolution of physics as a discipline. Fifty years ago, the formalisms were less daunting. A good physical intuition could usually be translated to an acceptable formalism. Much progress was made on that basis. Once the standard model was achieved, the balance shifted. These days most of the obstacles to further progress are inherent to the expressive power of the available formalisms. At one end of the spectrum you have people working within formalisms that are far too expressive (string theory) and hence far removed from any specific prediction. At the other end of the spectrum, you have people who take a step back and potter away within formalisms that might ultimately prove to be insufficiently expressive for the physics we actually have.

        If the string theorists have managed to demonstrate that the expressive power of string theory exceeds any practical potential for concrete prediction, that actually amounts to good progress. I see the present era of physics as being more about determining the advantages and disadvantages of the available formalisms (on the spectrum of insufficiency to excess sufficiency) quite apart from predicting actual particles, however nice that might be. The cost of each new fundamental particle discovered experimentally has increased exponentially. How could any serious thinker be surprised we ended up at this impasse?

        It has always been a problem with the psychology of earthlings that we undervalue negative demonstrations. From what I read (quite a lot, without understanding much of the math at all) it seems as thought Lisi is exploring a coherent mathematical system which at least contains certain essential features of known physics in an unusual combination. I regard that as a useful line of inquiry regardless of whether or not it is doomed with respect to describing the whole of known physics.

        Obviously, this places physics on a far different trajectory for the amount of work required relative to the progress achieved than the glory days of the mid 20th century. What I suspect is driving the social turmoil within the discipline is that society has not necessarily agreed to continue funding physics to the same level given this severe softening of trajectory. Funding continues on inertia despite original premises that are no longer true. Woit presses for a return to those original premises (short path from new theory to verifiable predictions), while ignoring that it might no longer be possible to progress on those terms due to vastly more constraints emanating from the formalisms themselves.
    • by Anonymous Coward on Thursday November 15, 2007 @09:44PM (#21373277)
      No offense to the OP, but Lubos Motl is well known by he physics community to be the academic equivalent of a hate monger. Sure, he's done some decent physics work, but he's pretty much impossible to work with and is instantly dismissive of anyone who doesn't follow the same path as him. And no one outside his circle of friends really listens to him all that much since he has a habit of not looking to carefully at the work of those he is criticizing.

      So I wouldn't pay attention to Lubos when he says that someone is a crackpot and their ideas aren't feasible. A lot of physicists just look at his comments as free publicity because if Lubos is criticizing it, it usually means that he feels threatened by it, therefore, it could have some promise if it at least got his attention.
    • by quarrelinastraw ( 771952 ) on Thursday November 15, 2007 @09:52PM (#21373371)
      The blog you linked to is a string theorist basically bitching about people who don't like string theory. Basically, someone insulted his religion and he's getting whiney.

      Here's what he says about Lee Smolin, author of The Trouble with Physics

      Smolin is a mediocre, slow thinker with a bad memory, below-average imagination, bad ability to focus and investigate details, and with kindergarten ideas - it is always hard to tell whether he is just joking when he talks about his childish ideas or whether he is serious - who is unable to learn the state-of-the-art physics at the technical level and who has never written a paper that would remain both valid as well as important among physicists who know their field for more than 10 minutes....
      Here's what he says about his beloved string theory:

      It's very clear that if someone dislikes string theory, she or he must dislike most of modern theoretical physics, too (Lee Smolin certainly does!). It's because string theory is nothing else than the crown, unification, or culmination of modern theoretical physics and all of its crucial results, insights, methods, principles, and values.

      No true academic speaks that way about any idea, whether he disagrees with it or not. That's not science, that's fanboi-ism.

      • by Pharmboy ( 216950 ) on Thursday November 15, 2007 @10:16PM (#21373593) Journal
        Wow, nice quotes. I think you nailed it with the "fanboi-ism" charge. And as a bonus, if in the second paragraph you replace "string theory" with "BSD" and "physics" with "operating systems", it still makes sense.

        It's very clear that if someone dislikes BSD, she or he must dislike most of modern operating systems, too (Lee Smolin certainly does!). It's because BSD is nothing else than the crown, unification, or culmination of modern operating systems and all of its crucial results, insights, methods, principles, and values.

        See? Gentoo, Linux, or anything else with fanboys. Try it with "PS3" and "gaming consoles", or any other combo. ;)
    • by Lord Grey ( 463613 ) * on Thursday November 15, 2007 @09:53PM (#21373373)
      From the referenced blogspot page:

      If you care how the forces and particles are supposed to be embedded into his group, it's like this. You start with a non-compact real form of E8. You embed a G2 into it. Its centralizer is a non-compact version of F4. Now, you embed the strong SU(3) into the G2 while the non-compact F4 acts as the source of a "graviweak" SO(7,1) group that contains SO(3,1), a "gauge group" that is now fashionable in the crackpot circles to "describe" gravity, and SO(4), their source of cargo cult electroweak symmetry.

      Of course, this group plays a different role (in the vielbein formulation of general relativity) than the Yang-Mills groups and the fact that these two kinds of a group cannot be merged is the content of the Coleman-Mandula theorem to be discussed at the end of my text. Moreover, the fermions clearly can't arise from the connection because they have a different spin and statistics and they don't transform in the adjoint representation. For people like A. Garrett Lisi, it is not hard to unify everything with everything else because they don't know any difference between different concepts in physics.

      Now I know how my wife feels when my friends come over and we talk shop.

  • Pure Maths (Score:5, Funny)

    by BovineSpirit ( 247170 ) on Thursday November 15, 2007 @09:03PM (#21372893) Homepage
    From Wikipedia:

    The designation E8 comes from Wilhelm Killing and Élie Cartan's classification of the complex simple Lie algebras, which fall into four infinite families labeled An, Bn, Cn, Dn, and five exceptional cases labeled E6, E7, E8, F4, and G2. The E8 algebra is the largest and most complicated of these exceptional cases, and is often the last case of various theorems to be proved.
    "complex simple Lie algebras"?

    Mathematics needs some new words, I think. And they need to stop using 'simple' in this kind of context. What about; instead of 'simple' they use 'mindbogglingly complicated' and instead of 'complex', 'totally headfucking' making the statement a more accurate 'totally headfucking mindboggleing complicated Lie algebras'.

  • Genius? (Score:5, Funny)

    by kaiynne ( 181440 ) on Thursday November 15, 2007 @09:10PM (#21372955)
    From the wiki article

    It was discovered by Wilhelm Killing (1888-1890).
    Man at 2 he had already mastered complex mathematics. To think what he could have done if his life had not been tragically cut short...
  • by viking80 ( 697716 ) on Thursday November 15, 2007 @09:13PM (#21372971) Journal
    From TFA: "if written out in tiny print, would cover an area the size of Manhattan."
    Is that more than a LoC(Libraries of congress)?
  • by pugugly ( 152978 ) on Thursday November 15, 2007 @09:14PM (#21372985)
    If I'm reading this right anyway, which I may well not be.

    It's more a very good argument for what he thinks the solution will looks like. The mathematics is low enough that I can (barely) understand it well enough to follow the general argument, but certainly not well enough to be able to catch any oversights. But it's the first thing I've seen in a long time that looked simple enough I felt like I could hit the books and maybe get to a point where I *could* understand it properly. (He says, as if he's really done the last three or four things like that he promised himself he would do. My head exploded reading the first volume of "Art of Computer Programming" and I haven't got in gear to finish *that* yet either.)

    But it sure *looks* pretty.

  • by chill ( 34294 ) on Thursday November 15, 2007 @09:18PM (#21373031) Journal
    He calls it "An Exceptionally Simple Theory of Everything", but it is based off of E8 mathematics -- ...a complex, eight-dimensional mathematical pattern with 248 points first found in 1887, but only fully understood by mathematicians this year after workings, that, if written out in tiny print, would cover an area the size of Manhattan.

    He must be using a form of the word "Simple" that I am not familiar with.
  • by SirBruce ( 679714 ) on Thursday November 15, 2007 @09:56PM (#21373411) Homepage
    Since the 50s, particle physicists have found ways of classifying particles intro groups, much the way Mendelev classified elements into groups via the Periodic Table. When doing this, they discover "missing" particles that fit within a certain group but were not yet known, thus giving such groupings predictive power.

    Different groups have different symmetries. E8 is a group in Lie algebra. The group is "exceptional" and "simple" which is why the article is entitled tongue-in-cheekishly "Exceptionally Simple". The power and beauty of the E8 group has been known for a long time, and it's featured in many theories of physics that have tried to provide an framework for explaining the bewildered world of particles and forces that make up the universe.

    What this author has done is use E8 in a new way to come up with a potential new theory that unifies all the forces and fields. This is not *strictly* a theory of everything, as there's a lot more that has to be answered, but if true it provides a geometric model that can give us insight into the underlying principles that are involved, just the way the Periodic Table does for elements.

    The guy is no kook, but his theory leaves a lot to be desired. One problem is that E8 and other lie algebras and their associated symmetries have been well-studied for decades, and most all of them have run into intractable problems or incorrect predictions, so this may just be another beautiful theory that doesn't fit reality. Lisi uses a little-known method called "BRST connections" to make it all seem to work, which most physicists are unfammiliar with. Another is that his theory actually forces something physicists call as "spontaneous symmetry breaking" into the calculations to make it fit what we know to be true in the "standard model". Many people feel this is putting the cart before the horse; they would prefer a theory where the symmetry is broken in a "nautral" way and the "standard model" of the universe just naturally falls out of it. Lisi's theory doesn't really tell us WHY this is the case, it just says it is, but here's the symmetry that underlies it and which you apply it to.

    Another problem is that the theory is still new and doesn't have an quantitative predictions as of yet... there's a lot of math that needs to be done, and it's not clear that such calculation *can* be done given the contraints of his theory. At issue is something known as the "Coleman-Mandula" theorem, which basically says a lot of what Lisi does in his theory doesn't work if there are subgroups in the algenbra that are equivalent to what are known as Poincare groups. Lisi says this doesn't apply to his new theory because it posits that the vacuum of spacetime doesn't have Poincare symmetry but instead is deSitter space. Well, the idea of deSitter space is well-known and has been examined in theoretical physics for decades as well, but there are a lot of problems with it. One is that the "Smatrix", which physicists love so much in making calculations in theories with Poincare symmetries, no longer works and simply becomes an approximation.

    The theory also predicts a very LARGE cosmological constant, which is contrary to observation, but there are other theories that explain how this is not actually a problem, so that might not be an issue. Perhaps the largest obstacle of the theory, once the calculations can be figured out, is that it pretty much obsoletes all of String Theory in favor of something like Loop Quantum Gravity. This will make a LOT of string physicists very unhappy.

    Lisi's theory will probably not be the last work in physics, but it might bring us a step closer to a real "Theory of Everything". The truth is physicists have been toying with similar geometric approaches and arrange particles in tables and trying to tie in gravity for decades now and every new theory looks great but never quite actually works out. The fact that the universe can *almost* be described via these methods probably tells us we're on the right track, but a true
  • Come on! (Score:3, Funny)

    by Ctrl-Z ( 28806 ) <tim@timcol e m a n . c om> on Thursday November 15, 2007 @11:21PM (#21374059) Homepage Journal
    Seriously, this story was just an excuse to combine the "theoryofeverything" and "surfing" tags.
  • Video (Score:5, Interesting)

    by 4D6963 ( 933028 ) on Friday November 16, 2007 @01:42AM (#21375149)

    I found a cool video [youtube.com] that explains it all.

    Well, personally I still don't understand a thing, but it looks cool anyways, and hey, what wouldn't one do for karma points!

  • Audio etc (Score:3, Interesting)

    by bjorniac ( 836863 ) on Friday November 16, 2007 @03:13PM (#21382351)
    Garrett recently gave a talk to the International Loop Quantum Gravity Seminar: http://relativity.phys.lsu.edu/ilqgs/ [lsu.edu] has slides and audio from the talk (and many other less controversial talks).

"If it's not loud, it doesn't work!" -- Blank Reg, from "Max Headroom"