An interesting (video) lecture by Frank Wilczek (Massachusetts Institute of Technology).
http://streamer.perimeterinstitute.ca/mediasite/viewer/?peid=9f6203be-df7b-46da-afcc-357f06ce4429Here's the blurb:
"Our present Core Theory of matter (aka “standard model”) was born in the 1970s, a Golden Age for fundamental physics. To date it has passed every experimental test, extending – by many orders of magnitude – to higher energies, shorter distances, and greater precision than were available in the 1970s. Yet we are not satisfied, because the Core Theory postulates four separate interactions and several different kinds of matter, and its equations are lopsided. In this lecture, Prof. Wilczek will describe powerful and extremely beautiful ideas for restoring unity and symmetry to the fundamental laws..."
