It's either all wrong, or it is one of the most important theoretical physics discoveries in history, a major step in the direction of a unified field theory.
In An Exceptionally Simple Theory of Everything, one Garrett Lisi, physics Ph.D and, yes, nearly-homeless surfer dude, suggests that E8 (described by the UK Daily Telegraph as an “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”) has this amazing property: E8, says, Dr. Lisi, contains the Standard Model, plus the symmetries belonging to gravity.
And, oh yes, the model makes the testable hypothesis that there are 20 more standard particles waiting to be found by supercolliders. (Twenty seems like rather a lot?)
Here's the abstract of the paper,
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.
This representation, to the very limited extent I follow it, doesn't tell us anything directly about the shape of the universe; rather it threatens to tell us something fundamental about the relationships between the particles and forces that make up and that shape the universe. While the “exceptionally simple” part of the paper title is — or had better be — a joke, the 248 dimensions of E8 are needed only for representation of relationships; the universe it describes has only the three dimensions we know, plus time, distinguishing this theory from string theory, which requires many more (even if some are very tiny).
Dr. Lisi's theory also makes pretty pictures.
Pictured above: figure 2 of Dr. Lisi's paper, “The E8 root system, with each root assigned to an elementary particle field.” There's also a cute movie of an E8 being rotated.
As noted above, there are already critics. Super-string advocate (and politically weird) Lubo Motl will have none of it.