Stanford University

Traditional ideas for testing unification involve searching for the decay of the proton and its branching modes. Currently, several astrophysical experiments are reaching sensitivities that allow them to explore supersymmetric unified theories. In these theories the electroweak-mass dark matter particle can de cay, just like the proton, and naturally has a lifetime of order 10^26 sec. We explore these theories and discuss the observable consequences. Interestingly, this timescale is being investigated in several experiments including Fermi/GLAST, HESS, and PAMELA. Recent potential evidence for such decays may be opening our first direct window to physics at the supersymmetric unification scale of 10^16 GeV, as well as the TeV scale. Additionally, in these supersymmetric unified theories, there are typically long-lived particles with lifetimes around 100 sec. Such decays would be recorded by a change in the primordial light element abundances and may well explain the present discord between the measured lithium abundances and standard big bang nucleosynthesis, opening another window to unification. These theories make concrete predictions for the spectrum and signatures in experiments such as Fermi, IceCube, and the LHC.

4:00 p.m., Physics Research Building (PRB), Room 1080

Reception at 3:45 p.m., Atrium, PRB