演講資訊

摘要：

Extragalactic background light (EBL), the integrated light flux densities outside the Milky Way, provides one of the most fundamental constraints on the formation and evolution of the Universe. While the cosmic microwave background (CMB) dominates the EBL energy budget, it is the cosmic optical (COB) and comic infrared background (CIB) that inform us most about galaxy formation and evolution. In this talk, I plan to first review the current understandings of COB and CIB, and then dig further into the submillimeter regime where we have seen recent progress. In the second part of the talk I will discuss the submillimeter galaxy (SMG), the dominant contributor to the submillimeter background, addressing key questions like where is it in distance? how does it form? and how would it evolve? During the discussion, a picture will naturally emerge where despite its important role in galaxy evolution, SMG is as mysterious now as it was discovered more than 20 years ago, causing headaches to most, if not all, state-of-the-art galaxy formation models.