Monday, 3:10 PM — MP1318A

I explain how Planck CMB measurements can be used to constrain parameters from the power spectrum, and then what various types of non-Gaussianity look like in terms of structures in the sky maps. Doppler and lensing non-Gaussian signals are detected at high significance, and I'll explain how these impact searches for primordial signals, the results, and how the non-Gaussian information can be useful to constrain cosmology.

Thursday, 2:10 PM — MP1318A

I will present three interesting problems with neat solutions. All three come from thinking about gravitational wave detection; but the latter two are actually of broader interest. The first problem is how to arrange a handful of gravitational wave detectors to obtain the best gravitational wave telescope. In the second problem, we imagine a collection of "nodes" (e.g. satellites) exchanging laser signals, and want to know how to construct interferometric observables that are insensitive to the phase fluctuations of the lasers. Finally, the third problem begins with the question: what is the most symmetrical arrangement of 4 satellites orbits? This simple question is the doorway to the interesting subject of choreographic crystals, which I will introduce.

Thursday, 4:10 PM — MP1318A

Screened Scalar-Tensor gravity such as chameleon and symmetron theories allow order one deviations from General Relativity on large scales whilst satisfying all local solar-system constraints. A lot of recent work has therefore focused on searching for observational signatures of these models and constraining them. If these models are to be viable then our own solar system is necessarily screened, however, this may not be the case for stars in Dwarf Galaxies, which can exhibit novel and unique phenomena. These new effects can be exploited to produce constraints that are far more competitive than laboratory and cosmological tests and in this talk, I will describe some recent and ongoing work using these phenomena to place new constraints.

Friday, 2:10 PM — MP1318A

Galactic-scale star formation depends both on the supply of gas and the efficiency at which that gas is converted into stars; both these factors vary with galactic mass. To study these processes together, galaxy simulations require a model for gas loss from stellar feedback and a star formation prescription tied to the molecular gas. In this talk, I will use cosmological simulations of dwarf and spiral galaxy formation with efficient supernova feedback and molecular hydrogen-based star formation to examine how star formation histories vary with halo mass. The resulting galaxies have rising rotation curves and realistic stellar masses and gas fractions. I will discuss how stellar feedback reduces the amount of low-angular momentum baryons to produce more realistic galaxies and how the efficiency of that gas loss is affected by the ISM model. Additionally, I will compare the gas outflows from galaxies of different masses.