Does string theory have rivals? The answer by the most cited theoretical physicist (and perhaps scientist) is that there are not any interesting competing suggestions. Be sure that people attending my popular talks (and sometimes radio hosts etc.) often ask the same question and I give the same answer. One reason, as Witten reminds us, is that ideas that actually have something good about them, like twistors and noncommutative geometry, are gradually identified as aspects of string theory itself and absorbed by string theory. It’s just how the things are.

— An interview with Edward Witten at a bizarre place

— Lubos Motl

2014.10.01 Wednesday ACHK