Our Places in the Cosmos: from the Big Bang to Life on Other Earths – Conference of Michel Mayor and James Peebles

Michel Mayor was born in Lausanne. After completing his studies in Physics at the University of Lausanne, he obtained his doctorate at the University of Geneva in 1971. Professor of astrophysics at the University of Geneva since 1984, he served as director of the Department of Astronomy from 1998 to 2004. Since 2007, he has been an honorary professor. While his thesis focused on the dynamics of spiral galaxies, he developed with some colleagues from the observatories of Geneva and Marseille a new type of spectrograph, an instrument able to measure the speed of stars, in order to verify their predictions. It is the beginning of his interest for the study of the movement of stars, the stellar kinematics, it is also the beginning of his passion for the development of more and more sensitive stellar spectrographs.
In 1995, he and his doctoral student at the time, Didier Quéloz, announced to the international scientific community the detection of the first planet outside the solar system, exoplanet 51 Pegasi b. An exoplanet orbiting around a star comparable to our Sun, about fifty light-years from Earth. This incredible announcement paves the way for thousands of researchers and thus launches the "century of exoplanets", more than 5000 to date.

James Peebles was born in St. Boniface, near Winnipeg, Canada. After attending the University of Manitoba, he continued his studies at Princeton University in the United States, receiving his doctorate there in 1962. He remained at Princeton for the remainder of his career, becoming an assistant professor in 1965 and a full professor in 1972. He became the Albert Einstein Professor of Science in 1984 and a professor emeritus in 2000. He is widely regarded as one of the world's leading theoretical cosmologists since 1970, with major theoretical contributions to primordial nucleosynthesis, dark matter, the cosmic microwave background, and structure formation.
James Peebles’ theoretical framework, developed since the mid-1960s in in the field of physical cosmology is the basis of our contemporary ideas about the origins of the universe. The cosmic background radiation is a remaining trace of the formation of the universe. Using his theoretical tools and calculations, James Peebles was able to interpret these traces from the infancy of the universe and discover new physical processes. The results showed us a universe in which just five per cent of its content is known matter. The rest, 95 per cent, is unknown dark matter and dark energy.

James Peebles was awarded half the Nobel Prize in Physics in 2019 “for theoretical discoveries in physical cosmology”, the other half was awarded jointly to Michel Mayor and Didier Quéloz “for the discovery of an exoplanet orbiting a solar-type star”.