Abstract : In certain models of a QCD axion, finite density corrections to the axion potential can result in the axion being sourced by large dense objects. There are a variety of ways to test this phenomenon, but perhaps the most surprising effect is that the axion can mediate forces between neutron stars that can be as strong as gravity. … Read More
Abstract: “I will discuss the one-loop divergence structure of effective field theories from Z3 and Z7 orbifold compactifications of the heterotic string in the U(1)K superspace formalism and its regularization through the use of Pauli-Villars fields.The conformal and chiral anomalies for the two theories are determined in this scheme by matching the chiral anomaly to string calculations. In particular, I … Read More
Abstract: The production of Higgs boson pairs at hadron colliders may allow for direct measurements of the trilinear Higgs coupling in the future. Deriving reliable theoretical predictions for this process is, however, uniquely challenging because it is induced by loops of heavy quarks instead of tree-level couplings. Only recently a full fixed-order NLO prediction has become available and thus led … Read More
Abstract: Most current dark matter detection strategies, including both direct and indirect efforts, are based on the assumption that the galactic dark matter number density is quite high, allowing for the detection of rare events. Such a paradigm arises naturally if the dark matter self-interactions are weak. However, strong interactions within the dark sector give rise to large composite objects … Read More
Abstract: General relativityâEinstein’s theory of gravitationâhas been studied for more than 100 years. Over the past century, we have learned that the theory agrees with all available experimental and observational tests. At the same time we know that the theory is incomplete, as it leads to inconsistencies when coupled with quantum mechanics. The strong-field regime is our best hope to … Read More
Abstract: The next generation of axion direct detection experiments may rule out or confirm axions as the dominant source of dark matter. In this talk I will describe how to develop a general likelihood-based framework for studying the time-series data at such experiments to search for signatures of the QCD axion or axion like particles. I will illustrate how in … Read More
Abstract: Wouldn’t it be lovely if we could use the same variational approaches familiar from quantum mechanics to study quantum field theories? We can, of course; the real question is how do we do this efficiently? In this talk I will discuss the recent revival of approximate Hamiltonian diagonalization as a means to numerically study field theories, both of the … Read More