IPMU Colloquium

Speaker: Masahiro Takada (IPMU)
Title: Cosmic structure formation and weak gravitational lensing
Date (JST): Wed, Feb 17, 2010, 13:30 - 17:00
Place: Lecture Hall
Abstract: Part I: An overview of cold dark matter dominated structure formation scenario: the current status and issues

Part II: Galaxy clusters and gravitational lensing

Various cosmological observations are well explained by the predictions from structure formation scenario assuming two mysterious dark components, dark energy and dark matter---the so-called Lambda-CDM dominated structure formation scenario. Here dark energy is needed to explain the cosmic accelerating expansion, while dark matter is needed to explain properties of hierarchical clustering observed in large-scale structures. One of the most important predictions in the CDM model is appearance of self-gravitating objects, dark matter halos, which host galaxies and clusters of galaxies, astronomically most interesting objects. My research interest lies in observational cosmology, aimed at exploring the nature and properties of these dark components. In particular gravitational lensing effect is a powerful tool for this purpose. In this talk I will first review the current status of observational cosmology, and then talk about the recent results of our projects on gravitational lensing effects due to galaxy clusters.