Weak lensing: promise and problems

Series: 
The London Relativity and Cosmology Seminar
Speaker: 
Joe Zuntz (Manchester)
Date: 
March 11th, 2015 at 16:30
Room: 
See Talk Details
Abstract: 

Over the next decade wide field lensing lensing surveys will provide some of the strongest constraints on the history of cosmic acceleration and the large-scale behaviour of gravity. WIth a focus on my work in the largest current project, the Dark Energy Survey, I will discuss what these surveys really measure, what we can learn from them, and what outstanding questions we need to solve before we can make best use of them, namely: how do galaxies align with each other when they are formed? How does the presence of baryons affect cosmic structure on small scales? And how can we measure the redshifts and shapes of 1 billion galaxies? I'll illustrate these with work from our recent paper that investigate the whether lensing measurements and CMB results disagree about the amount of structure in the universe:http://arxiv.org/abs/1408.4742 - Room G. O. Jones 516