Our Universe is comprised not only of normal matter but also of unknown components: dark matter and dark energy. This Thesis recounts studies of dark matter haloes, using a technique known as weak... Show moreOur Universe is comprised not only of normal matter but also of unknown components: dark matter and dark energy. This Thesis recounts studies of dark matter haloes, using a technique known as weak gravitational lensing, in order to learn more about the nature of these dark components. The haloes analysed are both those surrounding individual galaxies and those encompassing massive galaxy clusters. In order to better study these haloes, new lensing software is developed and existing lensing theory is advanced in the context of this Thesis. As a result, new higher-order signals are detected and lenses are studied in greater detail than ever before. Show less
Over the past 15 years, the field of extragalactic astronomy has pushed to high redshift and our knowledge of natal galaxies has grown dramatically. Galaxies are now routinely detected at redshifts... Show moreOver the past 15 years, the field of extragalactic astronomy has pushed to high redshift and our knowledge of natal galaxies has grown dramatically. Galaxies are now routinely detected at redshifts z ! 6__7 (e.g. Bouwens et al. 2010; Labb_e et al. 2010; Oesch et al. 2010; Bouwens et al. 2011; McLure et al. 2011). However, there are fundamental concepts that are still poorly understood. How do galaxies get their gas? How does galactic feedback affect galaxy evolution? Show less
