The research detailed in this proposal seeks to build a bridge between recent advances in string theory and the forthcoming data from the LHC experiment at CERN. As supersymmetry often emerges as a property of the low-energy limit of superstrings, the proposal largely involves supersymmetric models of particles physics. To truly make contact with the observable world a candidate string model must succeed on three fronts: (1) it must produce the Standard Model gauge group, particle content and superpotential couplings; (2) it must allow for moduli stabilization and supersymmetry breaking that produces a realistic phenomenology; and (3) it must be capable of explaining any new physics signals found at the LHC and other upcoming experiments. This proposal seeks to attack each of these challenges. The first set of projects detailed in the proposal concern the issue of relating geometrical properties of compactifications to the resulting low energy theory. Using new techniques developed by the PI and collaborators, the vacuum manifold described by the moduli space of N = 1 supersymmetric gauge theories will be determined and catalogued. In particular, the vacuum manifold for the minimal supersymmetric standard model (MSSM) will be determined. In addition, phenomenologically interesting variants will be studied in an effort to find correlations between the physics of these theories and the geometry of their moduli spaces. This new way of thinking about supersymmetric theories should eventually lead to progress in the mathematics of top-down constructions of realistic string models. In the second set of projects the complete effective Lagrangian for gauge-charged matter will be developed for M-theory compactifications on manifolds of G2 holonomy. Such theories have yet to be studied in detail, though they are known to give rise to low-energy limits with N = 1 supersymmetry, non-Abelian gauge theories and chiral fermions. The final set of projects will investigate the challenges for extracting the underlying Lagrangian for new physics from the signals to be obtained at the LHC. The problem will be investigated from a number of angles among them, looking at correlated effects of new physics models on top quark observables and the study of new S U (3)-charged exotic quarks as suggested by many string-theory constructions. The impacts of this work on the broader community are many. Work on LHC physics lends itself very well to the participation of undergraduates in the LHC Olympics series of data challenges. A modified web-based version of these analyses will be developed as an adjunct to this proposal to let high-school age students experience the excitement of signal extraction and discovery at a simulated 'LHC'. In addition the PI will be participating in the Boston-area TheoryNet program.
