This proposal funds the research activities of Professors Csaba Csaki, Yuval Grossman, Peter Lepage, Liam McAllister, and Maxim Perelstein at Cornell University.
High-energy physics studies the most fundamental building blocks of matter and their interactions. There are several different ways in which to try to answer the biggest puzzles this field is currently facing. By colliding elementary particles at the highest energies to date, the Large Hadron Collider (LHC) is expected to yield new clues on the interactions of elementary particles at the shortest distances. By extremely precise measurements of the cosmic microwave background (CMB) radiation, the properties of the Universe and the type of matter and energy dominating it at early times can be studied. Finally, powerful computer simulations can be used to study the properties of the strong interactions. Pursuing all of these directions, the Cornell Particle Theory group will advance the national interest by promoting the advancement of science in one of its most fundamental directions: the discovery and understanding of new physical law. In his research, Prof. Csaki will develop new models that can explain the origin of mass ("composite Higgs models") and can be tested at the LHC. The research of Prof. Grossman will focus on the heavier versions of the fundamental particles making up matter (the charm and the bottom quarks) as well as on neutrinos, particles that are created in beta decays. Prof. Perelstein will investigate new methods by which new particles could be discovered at the LHC, as well as new models for the type of matter (the so-called "dark matter") that surrounds ordinary visible matter, but interacts very weakly with it. Prof. McAllister will try to characterize the physical laws of the very early Universe by using results from string theory, which is the best candidate for understanding the behavior of the gravitational force at high energies. Finally, Prof. Lepage will use powerful computer simulations and state-of-the-art techniques to obtain precision results for strongly-interacting matter. This project will also have significant broader impacts. The Cornell particle theory group will train graduate students and involve postdocs in their research, and thereby provide critical training for junior physicists beginning research in this field. They will also give public lectures on their research results, as well as regular lectures to local high-school students.
More technically, Prof. Csaki will investigate new approaches to the hierarchy problem, will examine novel types of Higgs sectors and composite Higgs models, and will study possible experimental tests of vacuum energy, as well as the effects of monopoles in supersymmetric theories. Prof. Grossman will explore the physics of the intensity frontier, including charm and beauty physics, CP violation, and neutrino physics. Prof. Perelstein will investigate physics questions that can be addressed with the precision Higgs program at the LHC and future colliders, such as the nature of the electroweak phase transition. He will also continue to provide theoretical interpretation of the LHC data, and explore novel models of dark matter. Prof. Lepage, as a co-founder of the HPQCD lattice QCD collaboration, will continue to develop and deploy new techniques for extracting important physics from nonperturbative QCD, with a strong focus on QCD backgrounds that must be analyzed to isolate new physics in heavy-quark physics and very high-precision quantities such as the magnetic moment of the muon. Prof. McAllister will investigate string theory and early-universe cosmology. He will characterize quantum-gravity constraints on inflation, explore new axion inflation scenarios in string theory, develop tools to compute effective theories in compactifications on Calabi-Yau hypersurfaces, and study the vacuum structure of string theory via random matrix theory.
