京都大学未来創成学国際研究ユニットセミナー(第9回)

“Cosmology with the Cosmic Microwave Background Light: then and now”

  • 日  時:2018年2月7日(水)15:30-
  • 場  所:京都大学基礎物理学研究所 湯川記念館 パナソニック国際交流ホール
  • 講演者名:Francois R. Bouchet (Institut d’ Astrophysique de Paris CNRS)

要旨

Cosmology enjoyed a remarkable development over the last century. Astronomical observations revealed that galaxies like our own are not distributed at random throughout space, but rather delineate a quite remarkable structure, reminiscent of the skeletal framework of a sponge. How could that be? We now have developed a compelling picture of how these galaxies and their distribution developed over time, under the influence of gravity. We trace their origin to the earliest moment of the Universe. Most effective in achieving the current understanding has been the study of the sky background light called the Cosmic Microwave Background. This light, which is invisible to the naked eye but easily measurable with modern sensors, travelled uninterrupted for 13.8 billion years throughout the Universe. It last interacted with the material content of the Universe when the universe was very much hotter, denser, and homogeneous than it is now. It thus bears witness to the prevailing physical conditions back then and shedes light on the process which generated the primordial seeds out of which structures grew. As a result, recent observations bring amazing confirmation of ideas put forward in the 80’s and open a window on physics in a range of scales, time and energies which was hitherto inaccessible. I will describe how we came to the arresting conclusion that we are the children of quantum fluctuations of the vacuum!

*This is also held as a lecture presentation organized by the International Research Unit of Advanced Future Studies.