We review the landscape of QCD axion models. Theoretical constructions that extend the
window for the axion mass and couplings beyond conventional regions are highlighted and …

Phase transitions in a non-perturbative regime can be studied by ab initio Lattice Field
Theory methods. The status and future research directions for LFT investigations of Quantum …

We review the theory and phenomenology of isosinglet vector-like quarks (VLQs). In recent
years, interest in VLQs has been increasing, due to their contributions to new physics effects …

These notes are an expanded version of lectures given at the 2022 TASI summer school in
Boulder, Colorado. One goal of these lecture notes is to (partially) bridge the gap between …

A bstract When the QCD axion is absent in full theory, the strong CP problem has to be
explained by an additional mechanism, eg, the left-right symmetry. Even though tree-level …

A bstract We analyze the Nelson-Barr approach to the Strong CP Problem. We derive the
necessary conditions in order to simultaneously reproduce the CKM phase and the quark …

Conventionally, the strong-$ CP $ problem is assumed to be a naturalness puzzle, with the
axion solution sometimes viewed as an ad hoc fix. Gravity is either ignored or taken as a …

A concise demonstrative summary of the Symmetric-Hybrid ring design for the storage ring
proton electric dipole moment experiment is presented. Critical issues such as lattice design …

The S-matrix formulation of gravity suggests that the θ-vacuum structure must not be
sustained by the theory. We point out that, when applied to the vacuum of general relativity …

Lattice gauge theory continues to be a powerful theoretical and computational approach to
simulating strongly interacting quantum field theories, whose applications permeate almost …