The Large Hadron Collider (LHC), slated to begin taking data in 2008, will engage a new energy frontier. However, there is great uncertainty as to what exactly will be seen. Nonetheless, there are strong indications that its discoveries will address fundamental questions. This proposal will leverage the data from this ambitious undertaking and other experiments to primarily explore two questions: What is the identity of the mysterious dark matter that permeates our universe? What is the physics of electroweak symmetry breaking? Disentangling the answers to these questions will be a decade-long program requiring cooperation between theorists and experimentalists. The PI has several particular focuses. One initial focus will be to examining exotic new physics signatures. As more data arrives, the emphasis will shift towards building models that answer these two fundamental questions in a way consistent with data. Deciphering these questions will require an understanding of not only particle physics data, but data from cosmological experiments. Taking advantage of the interplay between the celestial and terrestrial will allow the PI to gain additional insight into the fundamental questions he intends to explore. Another goal of this proposal is to ensure that the knowledge and excitement generated by current and upcoming discoveries in particle physics are broadly shared: from the general public through graduate students. The outreach effort under this proposal will be two-fold. First, an exhibit on particle physics and the LHC is planned at the Ruthven Exhibit Museum for Natural History in Ann Arbor. This exhibit should reach 20- 30 thousand visitors during its initial run, including over 10,000 school-age students, many from disadvantaged areas. Second, the general public will benefit from a series of Saturday Morning lectures (broadcast to a wider audience on cable television) on the physics of the LHC.
This project supported theoretical work supporting the hunt for new physics beyond the Standard Model, the theory that summarizes our current understanding of particle physics. While the recent discovery of the Higgs boson at CERN represents and important step, there are important clues that tell us that there is additional new physics that remains to be found. First, astrophysical measurements indicate that our universe is dominated by Dark Matter, which is not comprised of any particle in the Standard Model. Understanding what most of universe of made out of is a fundamental question that will help us better understand our place in the universe. Second, while we now know that the Higgs boson is largely responsible for giving particles their mass, we do not understand why it has the properties it has. Indeed, it is a puzzle why, in the face of quantum mechanical pressure, it remained light enough to be discovered at the LHC. The resolution to this latter puzzle should help explain why gravity is so much weaker than the other forces. (As an illustration of this fact, note that a paper clip can be held up by a tiny magnet, in spite of the entire gravity of the Earth working against it). The work under this proposal advanced the theoretical understanding of what forms the new physics that addresses these clues could take. Armed with this understanding, we know better how to hunt for the resolution to these puzzles it at future experiments. Moreover, this work is important for the interpretation from on-going data coming in from both LHC experiments and experiments that hunt for the Dark Matter. This work has placed results from these experiments in theoretical context. Broader Impact: This project supported the creation of an exhibit on the the LHC and the Higgs boson that was featured at the University of Michigan Museum of Natural History, a museum that is open to the public. This museum serves schoolchildren from not only Ann Arbor, but also children from disadvantaged schools, from areas including Detroit, Ypsilanti and the Willow Run School District. After the close of the run of the exhibit at the Natural History museum, the exhibit was displayed at the University of Michigan Shapiro Science Library. This project also resulted in several public talks on particle physics, with and emphasis on the LHC, the Higgs Boson, and Dark Matter. Several hundred participants attended these talks, and one of these, a Saturday Morning Physics lecture, was recorded for subsequent airing on local television, and posting on iTunes.
