Galaxies as Probes of the Universe: From Dynamical Models to the Inference of Cosmological Parameters

Presented here are a number of projects on topics relating to the dynamics and properties of the Milky Way (MW) and measuring the Hubble constant. First is a project studying the possibility of dwarf galaxy interactions forming moving groups in the solar neighborhood. This is done using several simulations of the MW with dwarf galaxies on different orbits, and searching for velocity substructures in these simulations. The resulting structures are often similar to those observed in the MW, while such structures appear much less frequently in simulations without a perturber. The second project uses a different set of simulations to study the formation of the Magellanic Stream. These simulations make some indications about how the stream most likely formed. They also can be used to look at which models for the MW produce a stream most like that which is observed, from which we can estimate the mass of the MW. Another project aims at resolving the tension over the value of the Hubble constant. The goal is to provide a measurement of this parameter that is independent of the methods that produce this tension, and thus avoids any errors in those methods