Speaker: Benjamin Joachimi  (UCL)

Abstract:

On-going and forthcoming spectroscopic and imaging surveys provide increasingly large and rich datasets for cosmology. To optimally exploit them, we need to improve our understanding of all steps in the data analysis methodology, and quantify their accuracy. I am going to present recent advancements in two areas that are of interest particularly for weak lensing measurements, the estimation of error covariance matrices and the intrinsic alignment of galaxies. While conceived as necessary evils to be dealt with on the path to precision cosmology, I will detail that both subjects have revealed interesting insights and fruitful links to pure statistics and galaxy evolution, respectively.