Newscientist reports on this article:

http://www.arxiv.org/PS_cache/arxiv/...711.0770v1.pdf

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.

Is this as exciting as it sounds or is this not new?

Very nice. I particularly like pages 17, 19, and 20.

Wow! And by a single author! This author - Garrett Lisi - is a pretty remarkable guy, too.

Of course the math he is doing is not exactly accessible to anyone without a PhD in mathematics, and then probably just a subset of those. (I didn't quite get that far. ) I see he consulted with John Baez and Lee Smolin, so.... I'm impressed!

Interesting that Lambda = 3/5 phi².... phi being a multiplet of Higgs scalar fields....

All I can say is, higher mathematics these days is really stratospheric.

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Everyone is entitled to his own opinion, but not his own facts.

I'll be interested to hear if Lisi gets any feedback from this presentation (he apparently gave yesterday) at....

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Everyone is entitled to his own opinion, but not his own facts.

Well, I'll definitely look at the Nov. 17 issue of New Scientist to get some insights directed more toward my level. I am excited by the following pair of sentences on page 29:

"Future work will either strengthen the correlation to known physics and produce successful predictions for the LHC, or the theory will encounter a fatal contradiction with nature. The lack of extraneous structures and free parameters ensures testable predictions, so [the theory] will either succeed or fail spectacularly."

Yes. I am no math expert. It looks like on of those things that you go, oh $ht, yeah, that's what it should look like - it seems complicated enough and simple enough at the same time. Not much of a science filter, but definitely a description of an E=MC2 moment in elegance. This'll give us a clue what that darned dark matter and dark energy stuff is about hopefully.

I hope it doesn't turn out like that awful night nine months before my brother was born when I was waiting for Santa.

Well, it meets one criterion at least: page 17 would make a great T-shirt.

Yeah, I've been going over and over it (HATE pdf format...) and I'm all excited whether I should be or not.

It's like when you give a girl your number and are really interested in her... and are sitting there wondering whether or not she's going to call...

Geez and wow. I just read over that paper. I loved the conclusion -- this theory will either succeed or fail spectacularly. No free parameters. This may be it. It's got that feel. Lisi may be a name that joins the pantheon with dear old "Uncle Al". Too soon to say, but I got the feel that I might be reading something, as it unfolded, that will be viewed in a 100 years the same way we now view Uncle Al's papers of 100 years ago.

Damn, I wish I could've understood it. I mean double damn, I wish. What little I did understand just gave me that feel. GR falls out of it, as well as the Standard Model. And the fusion gives us something more, some additional interactions not yet observered. That's where the spectacular success or failure will be.

Again, some of what little I did understand clicked. Torsion for instance. If you recall, I posted some lunatic ramblings about torsion (not that gravitational torsion is lunatic, just my ramblings about it), and how that goes beyond GR, adding a torsion field (a "twist" to space-time due to spin, point angular momentum). Involved in that complexity is a different way to deal with things, where the "connection" is more fundamental than the metric. Whatever that means.

Well, that language was in Lisi's paper, and clicked with me. Torsion and the spin-spin gravitational interaction are subsumed in what Lisi calls the "graviweak" interaction/force, which has additional "stuff" coming from a fusion of Electroweak and gravity. Or something like that.

Riemannian geometry is subsumed under a more general "fiber bundle" geometry where the connection is more fundamental than the metric. Again, whatever that means, but it clicks along with that torsion stuff.

And, the cosmological constant just falls right out of the thing, being dependent on the Higgs field stuff, someway somehow.

And from that, something else that struck me was the statement that under this theory, the fundamental background space-time, the backdrop against which all of physics plays, is thus deSitter space-time with Lambda given by the Higgs thingy. That struck me as a profound statement, although I don't reall know why.

And finally, Uncle Al is indeed smiling, I think, from whatever null geodesic beyond the boundaries of (deSitter?) he's riding. It's all geometry, looks like to me. All geometry. A much richer and complex geometry than he first divined, but still geometry.

Spectacular success or failure, indeed.

-Richard

Are we all feeling dumb now or what?

Surfer dude stuns physicists with theory of everything

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Everything I need to know I learned through Googling.

Feeling dumb? Nobody feels dumber that I do at this point. Oh, how I wish I could understand that. Just a glimpse is all. I'm intrigued by the additional interactions, the additional fields, this "graviweak" stuff. This is just a theoretical mathematical framework, getting SM and GR together, and all the ramifications (where predictions can be made that can be tested....hopefully) are not explored.

What lurks there in those additional interactions? What gravitional couplings are there? Is warp drive there, some way to make that Alcubierre bubble beyond what is now known? ........... Or something really, really different?

-Richard

As a non-mathematician, the title "An Exceptionally Simple Theory of Everything" made me wince so dramatically that the left hemisphere of my brain fogged out and the right one filed divorce papers based on cruel and inhuman treatment.

On a more serious note, I've always subscribed to finding the simplest answer to the big questions, as the simplest explanations are usually the right ones. But, in the end, I guess simplicity is all relative, eh?

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How many times have you been about to grasp the truth when somebody else suddenly yanked it out of your reach?

Yep. I didn't understand a word of it, as usual. Cool pictures, though. That's about all I got out of it, anyway.

So much to learn, so little time. It seems like the more you learn, the more there is to learn. I'm glad Richard knows some of it, though. Maybe he can help to explain it. Just geometry, huh? Can it be found by integrating stuff over four dimensions of space-time, then?

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Let's put together the pieces of The Grand Puzzle . (website)

"Let's define another operator, Sz, which we won't pay any attention to."
"This transformation will automatically make zero equal zero."
"It may be true that zero equals zero -- and that is certainly an equality -- but I don't want to go into the details at this time."

Same here.

I opened the PDF File and read everything.. and... my brain hurts .

The whole idea of having the Theory of Everything ...is always...theoretical .

I think I have to take out my Math books from College which is now married with dust and cobwebs for a decade now.

In Lisi's introduction, he states:

We exist in a universe described by mathematics. But which math? Although it is interesting to consider that the universe may be the physical instantiation of all mathematics, there is a classic principle for restricting the possibilities: The mathematics of the universe should be beautiful. A successful description of nature should be a concise, elegant, unified mathematical structure consistent with experience.

I am just not sure how much choice Lisi had in fashioning his theory to be 'beautiful.' Particularly since I recall another respected scientist saying....

"To be sure, beauty or the lack of beauty does not determine the truth, whatever John Keats may have thought." - Donald Goldsmith

Nevertheless, I expect Lisi knows what the heck he is talking about, and the way his E8 superstructure decomposes into the Standard Model of quantum physics with a Higgs field along with gravity and the other players in General Relativity is nothing short of.... eye-opening.

It will obviously take more than a brush up on Lie algebras, but that's apparently a good place to start.

It would indeed. But for ultimate simplicity, you could just have "E8" on the T-shirt. Don't need no bulky equation like E=mc²....

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Everyone is entitled to his own opinion, but not his own facts.

Well then, just for fun, shall we all learn together, of course some having more experience with this than others? Seems like the first course of action, at least for me, is to learn about the lie groups being discussed. What are those?

__________________
Let's put together the pieces of The Grand Puzzle . (website)

"Let's define another operator, Sz, which we won't pay any attention to."
"This transformation will automatically make zero equal zero."
"It may be true that zero equals zero -- and that is certainly an equality -- but I don't want to go into the details at this time."

Grav,

I just choked at that "what are Lie Groups?" question. Just flat out upchucked. I ain't the one to 'splain Lie Groups. They play a big part in the mathematical description of quantum field theory and all that good stuff.

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

Here is an article about E8, the puppy of interest here.

http://en.wikipedia.org/wiki/E8_%28mathematics%29

Please don't ask me to 'splain that. I wouldn't get -1's, but far more than that, -100s probably.

-Richard

Grav,

You wondered how it was "just geometry". Well, let Lisi speak for his own self, here:

All known fields and dynamics through pure geometry. That's why I said Uncle Al is smiling. That was his thing.

-Richard