The Commission, gathered in a packed hall, announced the winners of the Nobel Prize for Physics 2019 at the Press Conference this morning, 8 October 2019:
“This year’s prize is awarded for contributing to our understanding of the Universe and our place in the Universe”.
“The Royal Swedish Academy of Sciences today decided to award the 2019 Nobel Prize in Physics for one half to James Peebles for theoretical discoveries in physical cosmology and the other half in conjunction with Michel Mayor and Didier Queloz for the discovery of an orbiting exoplanet around a solar star “.
Nobel Prize awarded for “the new understanding of the structure and history of the universe and the first discovery of a planet in orbit around a solar star outside our solar system. The discoveries have forever changed our conceptions of the world “.
James Peebles born in 1935 in Canada, in the state of Manitoba. Is Professor Emeritus of Sciences at the Albert Einstein Chair at Princeton University.
Peebles and Dicke’s studies have contributed significantly to the Big Bang model, predicting cosmic microwave background radiation, the first “wanderings of the Universe”.
The cosmic background radiation is one of the proofs of the Big Bang model. It confirms in an almost overwhelming way the presence of radiation in the Universe emitted during the first moments of life of the Universe itself.
Michel Mayor, born in Switzerland in 1942, is Professor at the University of Astronomy Department of Ginevra.
Didier Queloz, born in 1966 in Switzerland. Is Professor of Astrophysics at the University of Geneva and at the Cambridge University Laboratories.
Together they discovered on 6 October 1995 an exoplanet, Pegasi 51 b orbiting around 51 Pegasi, a star similar to the Sun. This discovery took place thanks to the “Doppler Effect” and therefore to the study of the radial velocity of the star. Since then thousands of other exoplanets have been discovered.
During the conference, the word then passes to Ulf Danielsson, Professor and member of the Nobel Prize-giving Committee.
He explains: “69% of the Universe is dark energy, 25% is dark matter, while ordinary matter is only 5%.
We can compare the Universe to a cup of coffee. “- Fills more than half a cup -” This is dark energy – then adds “a little” milk: “This is dark matter” Let’s add a pinch of sugar : this is ordinary matter – this is what science has been dealing with over the last few centuries.
Until now. – Shows an image of the cosmic background radiation. “In the mid-1960s, James Peebles realized the importance of cosmic radiation. In the following decades he developed new theoretical tools and used them to discover the “dark” components of our Universe. Through his work cosmology has evolved into a science of precision based on mathematical foundations. Cosmology has matured in physical cosmology.
Michel Mayor and Didier Queloz focused on what concerns us most closely, on “sugar in the cup”. They studied an anonymous star, 50 light-years away, visible to the naked eye under clear and dark skies, in the constellation of Pegasus, the winged horse. They could not see the planet directly, so they had to use other methods.
When a planet orbits around a star, its brightness changes – there is a change in the color of the star. When the star moves a little towards us, the light of the star becomes more blue. If the star moves in the opposite direction, the light becomes redder. The effect is minimal.
The planet had unexpected properties. He was so close to his Sun that his year lasted no more than a few Earth days. Its temperature was 1000 ° C, and it was as big as Jupiter. Few expected this planet to exist. Now we know that there are many types of planetary systems. In our Galaxy, the Milky Way, there could be billions of planets. Some of them could be similar to our Earth. From the study of these exoplanets, we will learn a lot about the physics of the planets, how they are formed and evolve. And we will have a new perspective on our planet. ”
“The winners of this year’s Nobel Prize in Physics – concludes Danielsson – have painted a more strange and wonderful Universe than we could have imagined. Our knowledge and our place in the Universe will never be the same again. “