Speaker: Emma Beynon
Location: ERE2011 Madrid
Gravitational lensing is a powerful probe of gravity in the Universe. Nevertheless, theoretical predictions for lensing are often made using considerable simplifications instead of a full General Relativity approach. Here I present a detailed, fully General Relativistic model of gravitational lensing of light rays by a dark matter halo in an expanding spacetime. I will describe the physics entering the model, and explain how we use this to make a precise numerical simulation of lensing events in the Universe. I will discuss the effects observed in these simulations associated with varying the density distribution of the halo and the cosmological volume, and the effect of any cosmological constant which is present. I discuss the extension of this model to include pressure, in order to fully describe a halo in hydrostatic equilibrium on small scales.