Beyond the Standard Model Phenomena: From Model Building to Searches

The Standard Model (SM) of particle physics is an effective theory for describing the interactions of fundamental particles and their properties. In spite of countless experimental agreements with the predictions of the SM, we have good reason to believe that the SM is not a complete description of particle physics. This unknown description of particle physics which is beyond that of the SM is the focus of this dissertation. We start by studying model-independent flavor non-universal UV effects at proton-proton colliders, low-energy flavor physics, and exotic Higgs decays. We then discuss the details of defining an arrival time for a jet to better search for long-lived particles which decay hadronically. Next, we study how an extended Higgs sector with an approximate $\mathbb{Z}_2$ symmetry can affect electroweak precision observables, collider experiments, and cosmology. Lastly, we study a framework for a dark matter model where the dark sector was described by an approximate conformal field theory at early times.