Smashing for Strings?
The box “Five Goals for the LHC” in “The Coming Revolutions in Particle Physics,” by Chris Quigg [Special Report: The Future of Physics], does not mention anything related to string theory as a goal of the upcoming Large Hadron Collider (LHC) at CERN. Are any experiments planned for the LHC that could either support or falsify the theory’s claims, expectations or predictions?
QUIGG REPLIES: String theory is not at the point of making specific predictions for the LHC, but the LHC might make observations that would encourage the string theory project. The discovery of supersymmetry would raise hopes that the incorporation of gravity that string theory has envisaged is a good path. Evidence for extra dimensions could likewise be seen as supporting some string theory ideas. On the other hand, observing certain kinds of new strong interactions might discourage the idea that strings will soon have relevance to our experiments.
Because string theorists are not yet able to compare a measured number with a predicted one, much of the impact will be in the form of a conversation between an experiment and threads in the string theory worldview. Even before it has begun operation, the LHC has influenced some prominent string theorists to put the theory aside, for the moment, to concentrate on theoretical problems that promise a more immediate dialogue with LHC experiments.
Note: This story was originally printed with the title, "Letters".