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."
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)
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.
Thank you for this summary, it's completely accurate.
-Garrett
(Yes, I'm the author of the paper. Hey look, my server's melting -- must of hit slashdot...)
Ha! I agree.
-Garrett