Séminaire du Prof. Abhay Ashtekar au CPT
Nous sommes heureux de vous annoncer que M. Abbay Ashtekar (Institute for Gravitation and the Cosmos & Physics Department The Pennsylvania State University), actuellement accueilli au Centre de Physique Théorique, donnera un séminaire d’intérêt général le mercredi 15 mars 2017, de 15h30 à 16h30, en amphithéâtre 5 du Centre de Physique Théorique.
In the inflationary paradigm, the very early universe is described using quantum field theory in cosmological space-times. In particular, the origin of the large scale anisotropies in the CMB is traced back to vacuum fluctuations of operators representing cosmological inhomogeneities. However, one then assumes that after a certain stage during inflation, dynamics of these inhomogeneities is well-described by the classical theory. This so-called `quantum to classical transition’ is at first puzzling and has drawn quite a bit of attention. In this talk I will first elucidate this issue, explain why some of the reasoning is incorrect, and arrive at a precise statement of why and how classical behavior emerges. Discussion will not assume any details of inflation, or even cosmology, and will be framed in the language normally used in quantum mechanics.