How did inflation actually happen? Precision measurements of statistical properties of primordial fluctuations generated during inflation offer a direct probe of the physics of inflation. When we calculate statistical properties of primordial fluctuations generated during inflation, we usually assume that the initial state of quantum fluctuations is in a preferred vacuum state called Bunch-Davies vacuum. While there is some motivation for choosing such a state, this is an assumption, and thus needs to be tested by observations. In this talk I will present new probes of initial state of quantum fluctuations during inflation: the 3-point function of the cosmic microwave background anisotropy, the 2-point function of galaxies, and a spectral distortion of the thermal spectrum of the cosmic microwave background.<\/p>\n","protected":false},"featured_media":0,"template":"","tags":[],"seminar_category":[],"acf":{"s_now_accepting":true,"s_date_order":"2012-07-23 15:30:00","s_date_end":null,"s_date_text":"","s_text":"Eiichiro Komatsu","s_place":"KMI Science Symposia (ES635)","s_place_other":"","s_categoryother":"CTOm KMI seminar","s_poster":"