报告人简介：2000毕业复旦大学，2006年获哥伦比亚大学博士学位。2006-2009年在UC Berkeley作博士后，
2009年－至今为UT Austin TCC Fellow。研究方向为理论宇宙学，包括弱引力透镜、大尺度结构以及宇宙
再电离。

报告摘要：
On large cosmic scales, foreground density fluctuations cause weak and
systematic shape distortions of background galaxy images through the weak
lensing effect. The lensing-induced weak shape distortion is the so called
cosmic shear, which is a direct and clean probe of the foreground structure
of our Universe. I introduce a new and robust method for measuring the
cosmic shear signal from galaxy shapes. It is so far the only method that
can solve most of the major technical problems in cosmic shear measurement
in a mathematically well-defined way. Its main features include:

1. It corrects for the point spread function;
2. It corrects for the photon noise;
3. It breaks the conventional signal-to-noise limit;
4. It uses simple & exact Math;
5. Shear measurement can be made accurate even to the 2nd order in
shear using this method without modifying the observables. This
feature is particularly useful for constraining foreground cluster
mass using weak lensing.

I include numerical examples, as well as a discussion of some prospects for
the future.