In the near future the Large Hadron Collider (LHC) will come on line providing an unprecedented opportunity for particle theorists to probe the nature of fundamental interactions in the Tera-electronvolt region. The PIs present a detailed program for the analysis of event signatures at the LHC that would provide the key to the discovery of new physics. Analysis of such new physics in the framework of grand unified theories (GUTS), string theories, and theories based on D branes are proposed, including issues related to quark-charged lepton- neutrino textures and proton stability. Updated signatures for detection of possible TeV-scale black holes will be explored. The effects of possible TeV-scale string excitations in multi-gluon scattering amplitudes underlying multi-jet production processes will be investigated. It is also proposed to test models of CP violation in sparticle (Supersymmetric partners of Standard model particles) production and decays (in the CMS and the ATLAS detectors) at the LHC and from the data on B decays from LHCb. Additionally, physics of extra U(1)'s which may be the remnants of GUTs and strings below the symmetry breaking scale will be investigated. In the field of particle astrophysics, a major neutrino telescope (IceCube) will be operating at full acceptance in several years, and a number of high energy gamma ray facilities are online now or will be so in the very near future. The research proposed will show how measurements at these installations, as well as at the Pierre Auger Laboratory ground array, can permit simultaneous advances in astrophysics and particle physics, probing TeV scale black holes, quantum decoherence, non-seesaw origin of light neutrino masses and neutrino stability. The proposed research projects of this proposal will contribute in an important way to the discovery of new physics beyond the Standard Model. Such a discovery will have important implications for the development of high energy theory, string theory and particle-astrophysics in the coming decades. One of the PIs, Tomasz Taylor,is the coordinator of the Boston Theorynet outreach program. This program aims at explaining to general audiences what theoretical physicists do to students in high school classrooms and to teachers in individual meetings with theorists. Its main component is the direct interaction between physicists, high school students and teachers, through question and answer sessions and presentations during regular class hour visits and after class.
This award funded the research of four principal investigators, all working in the area of fundamental particle physics beyond the Standard Model. The goals of this research effort include: (1) understanding whether supersymmetry is a property of the laws of physics at low energies -- that is, do all known fermions have bosonic partners that are yet to be discovered in collider experiments, (2) establishing that string theory provides a comprehensive theory of quantum gravity and particle physics which makes testable predictions, and (3) demonstrating how new theories of particle physics can leave a quantifiable imprint on cosmological observables. Over the time period represented by this award, the principal investigators demonstrated the following: (1) that scalar matter fields, and fermionic force carriers, may indeed still be present at low energies yet have escaped detection at the LHC for a number of reasons, (2) that the recent discovery of a Higgs boson with mass of 126 GeV/c^2 is consistent with precisely this notion of heavy scalar matter, (3) that future measurements of supersymmetric matter will be able to identify the nature of dark matter in our universe, including the composition of the wavefunction of this dark matter particle, (4) that extensions of the SO(10)-based grand unification model can solve long-standing issues of proton stability while providing novel signatures at the LHC, (5) that the most-studied models of string theory give rise to spectra of superpartners that are generally not in conflict with current LHC search results, except in certain classes of heterotic string theory models, and (6) that recent measurements in astrophysics and cosmology, such as BICEP and IceCUBE, may suggest additional degrees of freedom beyond those of the Standard Model were present in the early universe. The work conducted in this award has involved high performance computing, numerical and comptational algebraic geometry, and mathematical physics. As such, the work supported by this award can truly be considered interdisciplinary in nature. Furthermore, the work involves two dozen collaborators, including graduate students and postdocs at Northeastern University, that span all the continents. Work was disseminated through seminars and colloquia, workshops, and major international conferences. The outreach component of this award is the TheoryNet program, which pairs theoretical particle physicists with high school physics instructors throughout the greater Boston metro area, and well into neighborhing states. Participants come from all Boston area universities (MIT, Harvard, Boston U., Brandeis, Tufts, U. of New Hampshire, Rhode Island College, and Northeastern University). The goal of the outreach program is to inform high school students of the reality of careers in physics, particularly in the academic direction, de-mystify concepts that are in the public eye (such as the Higgs discovery, dark matter and dark energy, black holes, etc.), and promote scientific careers generally. Faculty travel to area high schools and give presentations that range from mostly biographical to mostly question-and-answer. It is estimated that 2,000 students are reached by Theorynet physicists each year, in a diversified cross-section of public and private schools in urban, suburban and rural areas. The program is highly appreciated by teachers, students and their parents. Students have had negative pre-conceived notions of science professionals corrected by direct interaction with university faculty. Students are often encouraged to learn that even some fanciful speculations can find a home in theoretical physics, where there truly are `no dumb questions.'
