John Baez posted a link to a page where he has movies (for viewing or downloading) of his low level discussion of E8 and Kostant's more particular discussion of E8 and Garrett Lisi's recent Theory of Everything paper.  There are also some links that point to purely group-theory criticism of Lisi's efforts.  If you have questions, I am not the person to ask.  I'm about a quarter of the way through the elementary one.

E8 is a Lie group that gives rise to some beautiful graphic representations (maybe this should be cross posted to math art) and also arises in string theory, so perhaps it is not surprising that Lisi was able to make interesting use of it.

crossposted to my journal and physics

Dennis Overbye has an essay on the New York Times (registration required) lamenting the prediction that soon we won't be able to see anything but what's in our local galaxy cluster.  (And that might have merged into a single galaxy.)  That will long have ceased to interest anyone around here, but he is thinking of future societies trying to figure out how the universe works, and not having our ability to see far-off clusters - expansion will have taken them beyond our light horizon.

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Are discussed at http://www.nature.com/news/2006/060703/full/442009a.html .  Note extended list links at the bottom.  Thanks to ase for the heads-up.

I just posted a comment in the physics community, referring to John Baez' website.  I'll make an entry here for reference.

He seems dedicated to writing clearly and simply on many math and physics topics.  The general entry to his stuff is    John Baez's Stuff  .   He writes to many levels.  Much is understandable by the interested layperson.  Other topics are more for specialists and can be easily skipped. 

Lots of good physics and math there.  Also a pointer to the Physics FAQ as well as links to other useful sites.