Abstract: Over the past decade, field theorists have developed a novel framework for thinking about global symmetries which has enormously generalized our understanding thereof. Quite recently, my collaborators and I have established positively that past being a useful formal tool, such generalized symmetries are indeed present in models that we care about as particle physicists—and furthermore understanding them can lead … Read More
“If a light axion is present during inflation and becomes part of dark matter afterwards, its quantum fluctuations contribute to dark matter isocurvature. In this article, we introduce a whole new suite of cosmological observables for axion isocurvature, which could help test the presence of axions, as well as its coupling to the inflaton and other heavy spectator fields during … Read More
The fundamental nature of dark matter (DM) so far eludes direct detection experiments, but it has left its imprint in the large-scale structure (LSS) of the Universe. I will present a search using cosmic microwave background (CMB) and galaxy surveys for ultra-light DM particle candidates called axions that are well motivated from high energy theory. In combining these datasets, I will discuss … Read More
Abstract: I will present a study of an interesting strongly coupled chiral quantum field theory. This theory has the same particle content as the simplest grand unified theory of the Standard Model. I will employ tools such as ‘t Hooft anomaly matching and softly broken supersymmetry to analyze the non-perturbative dynamics of the theory. I will describe some interesting results … Read More
Abstract: In this talk, we begin with a general investigation of the non-relativistic quantum mechanical potentials generated between fermions by various classes of QFT operators. Evaluating their singularity structure, we find that the potentials are nonsingular. In analogy with the Swampland program in string theory, we propose the Quantum Mechanics Swampland, in which the Landscape consists of non-relativistic quantum mechanical potentials that … Read More
Abstract: Gravitational wave signals can reveal new information about the dynamics of the early universe and are complementary to other probes. I will use several examples to illustrate what kind of signal we should expect and what we can learn from them.
Abstract: Cosmological phase transitions that proceed via nucleation of bubbles are a well-motivated possibility both in minimal extensions of the Standard Model as well as in more general hidden sectors with their own dynamics. In this talk, I will discuss the dynamics of expanding vacuum bubbles in the presence of massive dark photons that gain mass across the interface — with a special focus on the … Read More
Abstract: Direct detection experiments looking for sub-GeV dark matter (DM) through nuclear recoils have already placed constraints down to DM masses ~ 100 MeV with energy thresholds of ~ 10 eV. Challenges in achieving sensitivity to lower DM masses include precisely calculating the DM scattering rates through multi-phonons, and understanding as well as mitigating backgrounds in low-threshold detectors. In this seminar, … Read More
“Due to the large scale separations involved, matching is an essential laborious step in the computations to compare high-energy new physics models with experimental data. Matchete is a Mathematica package that automates the one-loop matching from any generic ultraviolet (UV) model to a low-energy effective field theory (EFT) including, but not limited to, SMEFT. The program takes as input a … Read More