An Exceptionally Simple Theory of Everything

[BryanP]

Thanks, just printed it.

 

[polystethylene]

As a fourth year masters student just starting to learn about symmetry groups and unification and the like, this is something of an eye-opener, in that I have no idea what's going on in this paper. From what I can gather from the sections of prose though, it seems like a pretty beautiful and simple theory, congratulations garrett.

 

[Valjean]

Basis rather than theory of everything?

And just maybe...to get to the fundamental condition that everything is based on...attraction exists between everything. Its strength between any two things, in any given circumstances, depends exactly on the amount of mass involved. So exact that the source of that attraction must be a the smallest, indivisible bit of mass there is. To have the same result you have to have the same ingredients. Some of those bits collect, because of the attraction, into units and others orbit around them in regular frequencies and amplitudes. As those motions cause any given two bits to move closer and further relative to each other the attraction between them increases and decreases accordingly. Energy frequencies of attraction that travel outward until they meet another bit causing its orbit to alter ever so slightly but still altered...maybe even a bit inside your eye which passes to the next, etc. So, how might that attraction exist? Consider. Nothing. Starting from the same place as the bang, formation of strings, etc. a separation, a compression of space into one bit of compressed space surrounded by expanded space created by the same action, like a teeter-totter, which then "banged" causing it to shatter into countless bits each still surrounded by the expanded. space. Or maybe there was just a crystalization producing the same thing in one action. Maybe a bad example but...a solid rubber ball. Draw rubber into points of compressed rubber each surrounded by expanded rubber pulling any two compressed points towards each other but can't move them because of the equality of pull between all of them. Move one, however, and a never ending dance starts because of the ineaquality of pull aka attraction. Back to the bits. Some compressed points (energy) our instruments can detect that we view as matter. Others don't. Dark matter? We don't detect it but it still has its attraction basis. We don't detect the expanded space (energy) as such but it is a necessary component for attraction to exist. We detect the results of its being but not it directly. Dark Energy? Or maybe it's all hogwash.

 

[timex]

Where is time in the theory?

 

[rntsai]

Where is time in the theory?

timex,
I think time translation corresponds to one of the generators of one the two
d4 subalgebras; which one I haven't figured out myself yet. The d4 corresponds
to an so(8) (or so(1,7) or so(2,6)); I think somewhere in these so's there's
an so(2,4) related to the poincare algebra; time translation is one of the
15 generators of this so(2,4); x,y,and z translations are another 3,...
My understanding of this at this point is very vague and possible wrong,
but maybe someone can clarify.

 

[Denton]

I really wish I could understand this... its just currently out of reach.

 

[marcus]

On 6 December Smolin posted this paper, and then entered discussion at the blog Cosmic Variance (where content-free insults by anonymous posters are permitted)

http://arxiv.org/abs/0712.0977
The Plebanski action extended to a unification of gravity and Yang-Mills theory
Lee Smolin
13 pages, one figure
(Submitted on 6 Dec 2007)

"We study a unification of gravity with Yang-Mills fields based on a simple extension of the Plebanski action to a Lie group G which contains the local lorentz group. The Coleman-Mandula theorem is avoided because the theory necessarily has a non-zero cosmological constant and the dynamics has no global spacetime symmetry. This may be applied to Lisi's proposal of an E8 unified theory, giving a fully E8 invariant action. The extended form of the Plebanski action suggests a new class of spin foam models."

==================
Two things are especially notable. On one hand, Smolin together with several others (Wan, Hackett, Kauffman, Bilson-Thompson...) is currently working on an entirely different LQG unification program----a scheme for merging matter with geometry that COMPETES with Garrett Lisi's E8 approach. It uses topological features such as twists and braids in the network to represent matter and attempts to realize the standard menu of particles.

On the other hand, in Smolin's paper he offers a second level of competition. Because he proposes to go partway with Lisi but (1) allow for using a different group from E8 should that turn out necessary and (2) realize fermions in a radically different way from how Lisi goes.

So Smolin is offering two competing unification approaches, one which looks somewhat Lisi-like and another (involving more collaborators) which is completely different. I think the aim is to get ideas out there where they can be examined and discussed, presumably in a professional way, and perhaps further modified. The game being not to win arguments or score points but to see if any variations of these ideas could be worth pursuing---maybe even right.

So then that was 6 December and then there was the discussion at CV blog presided over by Sean Carroll. that may have now burnt out and be more or less over. not sure but maybe. have to go, back later

Lee seems to have stated his conclusions from the discussion in the form of a long post, which is an interesting document in itself.
http://cosmicvariance.com/2007/11/16/garrett-lisis-theory-of-everything/#comment-306890
It comments on the blog-context as well as the physics content of the discussion in that CV thread.

One thing that seems very obvious but which no one has remarked on, is that in TRADITIONAL pre-blog scholarly discussion, as soon as Smolin posted his paper (Arxiv 0712.0977) responding to, utilizing, and diverging from Lisi's. Then the obvious thing to do would be for Distler to post a critical response IN THE FORM OF A SCHOLARLY PAPER ALSO ON ARXIV. Traditional scholars do this all the time---they post papers with titles like Comment on "The Plebanski Action Extended to a Unification..."
I have seen dozens of such papers. Sometimes they are published. Sometimes they are replied to with yet another scholarly paper by the original authors!

The advantage is that in an exchange of papers each person assumes responsibility for what they say and has the job of saying it clearly and carefully. Then anyone who is interested can see what each actually said and how they addressed each other's points.
By contrast in a series of BLOG COMMENTS it is very difficult to find and keep track of what people are actually saying because it is mixed in with a lot of anonymous trash and side-discussions. Blog commenters may also use innuendo or careless suggestive language because no one is being held accountable in the way they are with professional journal article format (footnotes, references, point-by-point organization that one can inspect and judge for clarity)

So there really is some merit to the classic way scholarly debate is organized and the classic journal article style. If anybody habitually avoids that format and seems to PREFER the more disorderly, time-consuming, and irresponsible Blog medium----if they have the professional status ensuring ready visibility on arxiv----then to me it seems questionable. I wonder why they insist on Blog-wallow when they could easily and clearly get their message across on HEP-TH.

 

[ccdantas]

I offer a clean, free-of-insults compilation/edition of what is (was) going on over at CV.

http://egregium.wordpress.com/2007/11/10/physics-needs-independent-thinkers/

Scroll down to "disclaimer".

For non-technical ramblings on the episode over at CV, see here

http://egregium.wordpress.com/2007/12/17/competitive-cycle/

and for my concerns on Lisi's theory and Distler's arguments, as well as on how far Smolin's work depends on Lisi's, see here:

http://egregium.wordpress.com/2007/12/11/garrett-and-smolin-to-boldly-go/

For technical discussions on Smolin's paper, I attempt to build a discussion here

http://egregium.wordpress.com/2007/12/07/the-plebanski-action-extended-to-a-unification-of-gravity-and-yang-mills-theory/

To which Smolin has posted a useful comment.

Thanks
Christine

 

[mitchell porter]

I wonder why they insist on Blog-wallow when they could easily and clearly get their message across on HEP-TH.

It may yet happen. But most of the blog discussion is ultimately a reaction to the mass media coverage of Lisi's original paper (except for Lubos Motl's post, which I think was an immediate earnest reaction to what he regarded as an absurd paper). There might have been one or two brief "comments", saying exactly what people have been saying on the blogs. Or it might have been ignored outside of LQG. As someone wrote at Wikipedia, "I don't think anyone here realizes how many wrong papers are posted on that preprint server every day. No researcher has time to debunk them - it would be a completely thankless and Sisyphean exercise. Instead, they just get ignored."

You could compare this case to Joy Christian's paper, earlier in the year, claiming a counterexample to Bell's theorem. That has received about half a dozen rebuttals at the arxiv, and no blogosphere flamefest. But even that paper was in New Scientist, so one cannot tell how much professional attention it would have received in the absence of journalistic attention.

There is actually one advantage to trial-by-blogosphere, and that is that general understanding may progress much more quickly. Look at how many exchanges there have been between Distler and Smolin on that thread at CV, and imagine if that had to take place by exchange of preprints! It would take weeks or months.

 

[marcus]

It may yet happen. But most of the blog discussion is ultimately a reaction to the mass media coverage of Lisi's original paper
...Or it might have been ignored outside of LQG. ...

You could compare this case to Joy Christian's paper, earlier in the year, claiming a counterexample to Bell's theorem. That has received about half a dozen rebuttals at the arxiv, and no blogosphere flamefest. But even that paper was in New Scientist, so one cannot tell how much professional attention it would have received in the absence of journalistic attention.

There is actually one advantage ...

I like the perspective you bring. A calm look at the whole picture.

What I get from you is a picture where even the despised popular media plays a part. Joy Christian posts on arxiv and gets plentiful rebuttals, themselves also on arxiv, partly thanks to agitation by the NewSci weekly hysteria machine.

I understand the advantage of blogs that you point out. The format itself demands rapid response. Comments quickly get covered up and lost in flurry. So quick volleys are exchanged. On the other hand there is something to be said for a slower format and more deliberate exchange. A discussionboard like PF seems to have somewhat longer-lived slower paced threads. As you observe, posting on Arxiv is even slower paced.

Sometimes it helps to say what is your Utopian vision, what you think would be ideal. What would seem ideal to me is if major figures like Smolin and Distler would confine themselves to exchange on Arxiv, in cool orderly style. And then let spectators including ourselves make noise about it. As a member of the mob of bystanders I feel confident that (with or without the help of NewSci and SciAm trombone sections) we could ensure that interesting debates on Arxiv do not go unnoticed.

Courtesy is (I hope) a separate issue. I think MORE courtesy should be required on blog and forum (than in unrecorded head-butting at the blackboard and coffeemachine). I find PF is somewhat unusual in that people actually have to be nice. Nastiness often gets deleted by the mods.

 

[marcus]

I offer a clean, free-of-insults compilation/edition of what is (was) going on over at CV.

http://egregium.wordpress.com/2007/11/10/physics-needs-independent-thinkers/

Scroll down to "disclaimer".

For non-technical ramblings on the episode over at CV, see here

http://egregium.wordpress.com/2007/12/17/competitive-cycle/

and for my concerns on Lisi's theory and Distler's arguments, as well as on how far Smolin's work depends on Lisi's, see here:

http://egregium.wordpress.com/2007/12/11/garrett-and-smolin-to-boldly-go/

For technical discussions on Smolin's paper, I attempt to build a discussion here

http://egregium.wordpress.com/2007/12/07/the-plebanski-action-extended-to-a-unification-of-gravity-and-yang-mills-theory/

To which Smolin has posted a useful comment.

Thanks
Christine

Christine, You have done a remarkable editing job! I like your blog format, where you enable only those comments which meet your standards. The tone is friendly and polite.

With enablement there is a slower pace, which allows your commenters time to have a normal life, and the discussion stays on track.

Your editing the CV script down to serious technical exchange between JD and LS had a surprising effect. there is no rudeness! nobody showing off how funny they can be. I didn't realize how much actual content there was. Your edited script goes up through 19 December. I am not suggesting you continue---you know best.

I was reminded of the folk-saying: "to make a silk purse out of a sow's ear." The CV comment stream was the ear of a pig, and you made a nice scholar's dialog out of it.
the change is almost funny.

Well, I have to go wash the dishes. I hope you and Mitchell think some more about these
blog+arxiv media issues. I will. We are gradually learning by examples what does and doesn't work.

 

[Ivan Seeking]

A note from Nature: Whatever happened to...

E8, that amazing mathematical structure?

E8 (or at least a 2D representation of it).American Institute of Mathematics/Peter McMullenIn March, researchers mapped a bizarre 248-dimensional object, an entity known in mathematics as E8. The map (which can be very prettily rendered in two dimensions) was touted as being useful to physicists interested in fundamental questions of quantum theory and relativity.

Then, in November, E8 surfaced again in reports of something claiming to be an exceptionally simple theory of everything, which basically involves sticking fundamental particles on various points of E8 and then looking at it in different ways to see how the particles relate to each other. The use of symmetrical structures in this way is fascinating and can be very powerful, and the story got lots of press after New Scientist highlighted it — not only because of the grand claim, but also because its source was a lone surfer with a physics degree. But physicists have since cast doubt on whether the idea is really new, really correct, or really able to make testable predictions. We’ll wait for the work to get peer reviewed for a journal, and for those crucial testable predictions to appear, before making a judgement.

http://www.nature.com/news/2007/071221/full/news.2007.390.html

 

[ccdantas]

Christine, You have done a remarkable editing job!

Thanks a lot, Marcus.

The whole CV episode was a complete mess. At the end, I was sad with how things ended.

I think blogs can serve as a serious place for technical or scientific exchanges in a friendly environment, but it is not easy, really. There are much more examples showing that it doesn't work than otherwise... I had to do some off-line moderation work. You must have time, energy and a sense of neutrality. I cannot say I have all these elements, specially the first ones...

Thanks,
Christine

 

[Coin]

We’ll wait for the work to get peer reviewed for a journal, and for those crucial testable predictions to appear, before making a judgement.

Incidentally, has/will Garrett's E8 proposals been submitted for peer review?

 

[Count Iblis]

Incidentally, has/will Garrett's E8 proposals been submitted for peer review?

His paper has already been reviewed by many people. So, he shouldn't bother to submit it to a journal. Submitting papers to a journal is for most papers a redundant exercise as http://users.ecs.soton.ac.uk/harnad/Hypermail/Amsci/1011.html" anyway.

 

[shalayka]

Thanks a lot, Marcus.

The whole CV episode was a complete mess. At the end, I was sad with how things ended.

I think blogs can serve as a serious place for technical or scientific exchanges in a friendly environment, but it is not easy, really. There are much more examples showing that it doesn't work than otherwise... I had to do some off-line moderation work. You must have time, energy and a sense of neutrality. I cannot say I have all these elements, specially the first ones...

Thanks,
Christine

I do agree that it was lugubrious that the conversation had to go the way it did, but it was becoming apparent that Lee Smolin had misstepped by giving unconditional praise to a paper that contained so many fundamental errors, and yet had no interest in describing what remained standing. All of this coming from someone who has such disdain for string theory as an unverified, unscientific meta-theory. The irony is ridiculous. Unfortunately for anyone who behaves in such a two-faced manner, I have a strong feeling that I'll be around for some time to come. I thought it was kind of cute that Sean Carroll doesn't realize that categorizing people as children is in itself an act of childishness. It just goes to show how high up in the clouds these peoples' heads are.

I suppose it's best said as "shut up and calculate". It's plainly obvious who's doing the talking, and who's doing the actual calculating.

 

[Ivan Seeking]

His paper has already been reviewed by many people. So, he shouldn't bother to submit it to a journal. Submitting papers to a journal is for most papers a redundant exercise as http://users.ecs.soton.ac.uk/harnad/Hypermail/Amsci/1011.html" anyway.

The folks at Nature seem to have a different opinion.

 

[Count Iblis]

The folks at Nature seem to have a different opinion.

Well, I don't see why the article would not be accepted in, say, PRD. The referees would perhaps only demand some clarifications on some contentious points. But papers are not usually rejected just because the referee doesn't agree with the author's conclusions.

 

[Electron17]

If Lisi's model turns out to be correct, does that mean all of physics is essentially solved and there will be nothing left to do? Or will the details need to be worked out for many years afterward?

 

[staf9]

If Lisi's model turns out to be correct, does that mean all of physics is essentially solved and there will be nothing left to do? Or will the details need to be worked out for many years afterward?

It means we have a LOT left to do, every question answered raises lots of new questions. In many ways, there may be even more that we don't know about if E8 Theory is correct. Some other people on these forums may be able to enlighten you more on this subject than I could.

 

[ericchou]

Sorry! I have a question about Lisi's theory.
What different between Lisi's theory and Chaos theory?
Thank you!

 

[mitchell porter]

Lisi's theory is a theory about what the fundamental particles are and how they interact.

Chaos theory is about a type of unpredictability which happens because small uncertainties are amplified into large uncertainties. Such "chaos" is a very general phenomenon and happens everywhere there are even moderately complicated interactions. You should look it up on Wikipedia to understand it better.

 

[ericchou]

Lisi's theory is a theory about what the fundamental particles are and how they interact.

Chaos theory is about a type of unpredictability which happens because small uncertainties are amplified into large uncertainties. Such "chaos" is a very general phenomenon and happens everywhere there are even moderately complicated interactions. You should look it up on Wikipedia to understand it better.

Sorry! If Lisi's theory is correct, then chaos & lisi's theory must be some relations between them.

and Do you believe the fate? I see something in the future, and it relate with chaos.

 

[mitchell porter]

Like I said, chaos is a very general phenomenon. Every physics theory since Newton's gravity allows chaos. Read the Wikipedia article.

 

[Xezlec]

I understand precisely 0% of this subject.

However, at http://golem.ph.utexas.edu/~distler/blog/archives/001505.html where Jacques Distler blasts the theory in an extremely rude and inappropriate way, demonstrating an inability to interact like a human being and making physics look like an ugly, ugly little world in the process, he sure does appear to win the heck out of whatever argument he's having, at least to my uncomprehending eyes.

Am I correct to understand that Distler claims to have mathematically proven that E8 theory is inconsistent with the existence of third-generation fermions?

I also noticed that G. L. responds and gets into a one-sidedly civil conversation in which he appears to admit that:

1. Distler is right, though Lisi thinks there's still something useful about his theory, and
2. Distler has correctly pointed out another error in his reasoning (see the "WHILE YOU'RE HERE" thread in the comments).

Is my understanding correct?

 

[Ivan Seeking]

In the news:

Did Garrett Lisi Have a Wipeout?

...Perhaps the longest public debate on the merits of Lisi’s theory took place primarily between Jacques Distler of the University of Texas at Austin and Lee Smolin of the Perimeter Institute for Theoretical Physics in Ontario, the latter of whom had been widely quoted in the media with unqualified praise for the theory. (Smolin says he was quoted out of context.) Smolin had also quickly written a paper suggesting ways to correct certain flaws in the E8 proposal. For the particles in the E8 theory to represent the known particles properly, the combination of smaller groups used to form the Standard Model must be embedded inside E8 in just the right way. Distler had demonstrated in his blog that this is a mathematical impossibility. So far as he was concerned, the theory was dead and not worth trying to resuscitate. Yet argument raged on over details of Distler’s proof and ultimately ended with neither side conceding. Lisi, incidentally, played very little part in these disputes.

Today the theory is being largely but not entirely ignored. Lisi, naturally, continues to work on it, as does Smolin. Lisi says that even if what Distler claims is true, it would only be true for the variant of E8 (“real E8”) originally used in his paper and that another variant (“complex E8”) would certainly work. Smolin argues that the press coverage gave the false impression that Lisi’s proposal was a finished work. “In reality,” he says, “almost every new theoretical proposal is first presented in a way that is flawed and incomplete, with open issues that need to be filled in... While Lisi’s proposal has exciting aspects, this is the case with it as well.”

http://www.sciam.com/article.cfm?id=garrett-lisi-e8-theory

 

[MTd2]

Garrett doesn't get any more exposition from the media or whatever simply because he, or his collaborators like Smoling, haven't published more about his theory. I hardly think he is ignored.

 

[atadaydin]

I think of a way to reproduce the CKM and PMNS matrices by taking quarks and leptons as vectors with 3 variables which is Σa Q_a e_a and L_b e_b respectively where Q and L are quarks and leptons respectively, a are colors and b are the generations. Then you may find that for particles it will be just w+xΦ and for antiparticles it's just the antiparticle of w+xΦ.

 

[saneisjus]

Perhaps could someone here point those of us that are having trouble overcoming the math here to a resource to clarify some of this?