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A New Theory of Everything?
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."
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!
Lubos Motl thinks it's pure bullshit ... so Lisi might
well be on to something :)
that the earth is going to get demolished any minute now.
"I bless every day that I continue to live, for every day is pure profit."
I smell an XKCD comic approaching....
I don't know about string theory but there is no way he pulled it off without rope theory.
I think some people have an entirely different definition of 'Simple' than myself.
then...
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!
;)
One swallow does not a fellatrix make
So it's not 42?
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
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.
http://aimath.org/E8/e8.html
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!
James Tiberius Kirk: "Spock, the women on your planet are logical. No other planet in the galaxy can make that claim."
here's the abstract for those wondering if they should download it:
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...
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Demented But Determined.
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.
Do it yourself, because no one else will do it yourself. [beta blockade 10-17 Feb]
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.
Request your free CD of my piano music.
I'm just waiting for Dvorak to denounce it. That'll be proof enough for me.
http://Communityville.com - A free place for new and old neighborhood webmasters to hang out.
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.
:-) 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.'
http://motls.blogspot.com/2007/11/exceptionally-simple-theory-of.html
'That's pretty cute!
"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'.
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)?
don't cut it off www.mgmbill.org
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.
Pug
An Invisible Entity of Vast Power whose existence must be taken on faith alone: Liberal Media
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.
Learning HOW to think is more important than learning WHAT to think.
Don't count on any help there. BadAnalogyGuy is like a leftover acorn in the summer, long after the bears have woken from hibernation.
If moderation could change anything, it would be illegal.
That would've been far more credible than Einstein... whom, I believe was long dead by the time Norris was conceived.
Chuck's an old dude! IMDB says for Chuck Norris: Date of Birth: 10 March 1940, Ryan, Oklahoma, USA
Wikipedia says for Albert Einstein: March 14, 1879 - April 18, 1955
So we've got at latest a 76-year-old Albert Einstein kicking the ass of a 15-year old Chuck Norris. Aw yeah.
Done with slashdot, done with nerds, getting a life.
Albert Einstein: died 18 April, 1955.
Granted, ol' Al would have been 61 years older than Chuck. But geez, is it really that hard to Google something before making an easily-checked claim like, "whom, I believe was long dead by the time Norris was conceived"?
Kids these days.
(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).
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.
Now I know how my wife feels when my friends come over and we talk shop.
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
This thread blows.
"I've got more toys than Teruhisa Kitahara."
Really well explained. Thanks.
Aging occurs because getting old is not evolutionarily beneficial (on the genetic level) in the original environment.
It's not so much that old age was selected against, it's that old age was not selected for. Obviously, as an organism grows older, its likely survival decreases due to predators, accidents, etc. Thus, those humans who had the gene "good health at old age" were just as likely to reproduce as those humans who did not have such a genetic advantage.
This is easily demonstrated at the bottom of the food chain, where prey organisms have very short lifespans but reproduce in large quantities quickly.
As to stopping aging, humans spend tons of effort and money on that (cosmetics, medicine), but it's not as simple as one quick fix, and short of genetically engineering our progeny, there's not going to be an immortal human.
Further, many genes that deal with aging probably have negative consequences later in life. Simple example: When we're young and learning, rapid growth and pruning of our neural networks is beneficial, but such cellular behavior could be negative for functioning in society at a later age.
In all honesty, I don't want to live forever. I want to get old and die, and I'd much rather know the secrets of the universe than work for hundreds of years and never retire. I think most people would agree - we all just want to age more comfortably.
Buckle your ROFL belt, we're in for some LOLs.
I wouldn't dismiss it yet. This is only one person.
Would you completely dismiss some new IT products because Steve Balmer speaks out calling it garbage? Probably not.
If lots of other people also spoke out calling it garbage then you might start paying attention. Now I don't know if this guy is the Steve Balmer of the physics community or not, but I know nothing about him so why should I trust his word over some other guy I know nothing about either?
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...
Seriously, this story was just an excuse to combine the "theoryofeverything" and "surfing" tags.
www.timcoleman.com is a total waste of your time. Never go there.
for a double major in two hard science disciplines. This isn't some foo-foo private university where they'll graduate you in 4 no matter what you do, it's two degrees from a University of California campus. Lots of classes that are required are taught only once a year -- or sometimes even every other year. If you can't get a spot in the class, tough. You get to spend an extra year. God forbid you have two required courses that are only taught once a year -- and they're scheduled at the same hour. It's not uncommon for people to get "out of sequence"... and spend an extra year. (I speak from experience on that front)
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).
Tsunami -- You can't bring a good wave down!
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.
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.
So what you're saying is that God doesn't play dice with the universe, he plays fizzbin?
Wow. I really, really hope that you are in education.
I have Bachelor degree in Physics (over 20 years ago) and I had no idea what the hell was being talked about. Your explanation is BRILLIANT. It does not assume readers are morons, does not portray science as magic, explains the subject in a way that even a layman finishes reading it with a better understanding than they started, and even manages to infuse some feeling for what the scientific discovery process is like. Amazing.
As someone who originally got into science because of Carl Sagan's Cosmos I can honestly say that if I had lecturers like you I would still be doing science. (not surprisingly, the subjects that I did best in had lecturers cut from the same cloth).
Thank you.
Here's the actual paper summarized as a microprocessor analogy (thought I'm sure someone will be happy to correct me where I get it wrong):
If E8 was a microprocessor, it would have 248 I/O pins. Lisi has discovered that if you put values for gravity into pins 1-12, you get electromagnitism results on pins 128-130. And if you put Strong Nuclear Force values into pints 64-76, then you get weak nuclear Force results from pins 192-204. If you put an electron into pin 36, you get a neutrino out of pin 189. Etc.
Because E8 seems to produce relationships between all of the fudamental forces (including gravity), Lisi is proposing that E8 must therefor be the key to describing and explaining all of the fundamental components of the universe.
If his ideas hold true (and thanks to the fact that they have testable predictions there's a way to know), E8 would be the starting point of describing anything in physics.
You cannot confine the discussion to simply cosmology. The TOE debate involves much larger aspects of physics and physics research, including all astronomy observations, satellite observatories, earth based observatories, particle accelerators, efforts to develop fusion power, etc. All of these I would classify under efforts to develop a TOE.
I would agree, that if one did a robust accounting, it would be open to some discussion as to where physics falls with respect to biology. At least in the U.S. I would tend to argue both are in the tens of billions of dollars range.
But my point stands. Any TOE does *not* impact each and every one of us to the extent that aging and for most of us our eventual deaths does. So one can easily argue -- solve living first -- solve the other stuff later.
Adding 20 new, unobserved, unproven particles makes for an "exceptionally simple" theory? Wonder what Occam would say about that.
I dunno, but the guy(s) who worked out the periodic table would likely approve:
(Dmitri taps his newly formed periodic table)
"Hmmm. Looks like some element should fit here."
(20 years later)
"Hey look! We've just discovered germanium, and it fits *right there*"
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Yah, OK, so please, you try it.
-Garrett
Holy crap! - I can read all the words, but none of it makes any sense. It's like the took regular English words and gave them all different meanings. I haven't felt this uncomprehending in a loooong time - and even the dumbness felt from quantum chemistry pales to this. Well, a lot of it falls out of this:
http://en.wikipedia.org/wiki/Group_theory
Which then gets you here:
http://en.wikipedia.org/wiki/Symmetry_group
Once you get those two, you can hit:
http://en.wikipedia.org/wiki/Differentiable_manifold
and you're very close to a general understanding of the shape (no pun intended) of what E8 is all about, and can dive into:
http://en.wikipedia.org/wiki/Lie_group
If it's any encouragement, I'm just finishing up my BS in Math, and currently taking a graduate course in algebra. And I don't get about 50% of the article. (note -- the wikipedia article has *nothing* to do with physics, it's just algebra & geometry) All I can say is, if you want to understand this stuff, grab a pencil and write down every definition you see. Every time you see a term whose definition you can't rattle off instantly, read it again.
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.
I found a cool video 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!
You just got troll'd!
He just plays with a loaded D20, apparently.
no apparently she plays with a spirograph ....
On the other hand, Grigori Perelman's proof of the Poincare Conjecture was only submitted to the ArXiv, and he actually turned down the Field's Medal.
>>No - it is called an exception lie algebra.
Not to be confused with a damned lie algebra, which is close to statistics.
The Problem with Wikipedia
It is dangerous to be right when the government is wrong.
Aaaah, and this is what differentiates Slashdot from sites like say, digg or reddit.
Thank you!
Ubuntu is an African word meaning 'I can't configure Debian'
Here is a video by NewScientist that tries to explain it to I hope this is not a dupe
http://uk.youtube.com/watch?v=-xHw9zcCvRQ
Not hard at all -- ! Goes like this: [Okay, I was wrong. It wasn't easy, and he won the debate.]
-kgj
-kgj
StoneCypher is Full of BS
Garrett recently gave a talk to the International Loop Quantum Gravity Seminar: http://relativity.phys.lsu.edu/ilqgs/ has slides and audio from the talk (and many other less controversial talks).
But I see something weird here (from wikipedia): "In conjunction with the 258-question relationship questionnaire, this is how all of the matches are delivered. One significant scoring factor is what may be called the honesty factor. Subtract the proposed divorce rate Dr. Warren wants in the US (10%) from the number of questions and...and...
HOLY CRAP!!!!
sig sig sig siggy sig