Towards Model-Independent Cosmological Probes in Weak Lensing

主讲人 (Speaker): 

张骏

主讲人单位 (Speaker's Institute): 

上海交通大学

邀请人 (Invited by): 

李霄栋

时间 (Time): 

星期三, 2019/05/29 - 15:00 to 16:00

地点 (Location): 

珠海校区海滨红楼17栋107 (Rm 107, Red House 17)

摘要 (Abstract): 

       Large scale galaxy surveys have brought us unprecedented opportunities in exploring various mysteries of our Universe, e.g., dark matter and dark energy, which may lead to exciting leaps in our understanding of fundamental physics. Weak lensing is a direct probe of the large scale structure, as only gravitational physics is involved. We show that to achieve robust constraints on cosmology, weak lensing measurements in both the underdense and overdense regions, as well as shape measurement itself, can be done in untraditional ways to reduce their model-dependences. In the first part of my talk, I show a new way of defining the underdense regions,and how to use their background lensing signals to constrain the equation-of-state of dark energy. Secondly, regarding the halo mass function measurement with weak lensing, I discuss a way of avoiding the Eddington bias and possibly many other sources of errors. Finally, I report the status of our Fourier_Quad shear measurement pipeline, which is accurate, fast, and model-independent.

主讲人简介 (Speaker's CV): 

张骏，上海交通大学教授，青年千人计划获得者。 研究兴趣在于宇宙大尺度结构的形成以及其背后的物理规律。理论上，研究集中于理解暗物质，暗能量，宇宙微波背景辐射，星系，星系团，宇宙再电离等课题。观测上，利用引力透镜效应来直接探测宇宙中的物质分布，并检测引力理论在宇宙学尺度的正确性。 2000年获得得复旦大学物理系学士学位， 2006年获得哥伦比亚大学物理学博士学位。 2006年－2009年 加州大学伯克利分校天体物理中心 博士后研究， 2009年－2012年 德州大学奥斯丁分校德州宇宙学中心 博士后研究。 2012年 - 至今 上海交通大学物理系 教授