George Fitzgerald Smoot
George Fitzgerald Smoot is a Astrophysicien and a American Cosmologiste born the February 20th 1945 with Yukon (Florida). It obtained the Nobel Prize of physics jointly with John C. Mather in 2006 for its contribution to discovered Anisotropie S of the cosmological diffuse Fond in 1992.
Biography
Studies and the first research
He studies the Mathématiques before turning to the Physique to the Massachusetts Institute off Technology where he obtains a Doctorat in Physique of the particles in 1970. He turns then to the Cosmologie and leaves to the Lawrence Berkeley National Laboratory where he starts a collaboration with Luis Walter Alvarez (Nobel Prize of physics in 1968) on the experiment CRAMP, a stratospheric Ballon charged to detect Antimatière in the high terrestrial atmosphere, whose presence was predicted by certain model cosmological today abandoned (the Théorie of the stationary state).
Then, it is interested in the cosmological diffuse Fond not very front discovered by Arno Allan Penzias and Robert Woodrow Wilson. A question unsolved at the time was that of the structure with large scales of the universe. Certain cosmological models predicted that the universe was to be in rotation, which was to leave a trace in the cosmological diffuse content in the form of a specific dependence of its Température according to the direction of observation. With the assistance of Shine Alvarez, it develops a differential Radiomètre allowing to measure the possible difference in temperature of the cosmological diffuse bottom between two different directions separated from 60 degrees. The instrument, assembled on a Avion U-2 made it possible to determine that the overall rotation of the universe was null (within the limit of the sensitivity of the measuring instruments). It especially made it possible to detect a variation in the temperature of the cosmological diffuse bottom corresponding to a Dipôle, interpreted like resulting from a Doppler effect of with displacement of the Ground compared to the area of emission of the cosmological diffuse bottom, called Surface of last diffusion. The existence of such a modulation was waited because there was no valid reason until the Earth, orbits about it around the Sun, him even orbits about it around the galactic Center is exactly motionless compared to the surface of last diffusion. On the other hand, the results of this experiment showed that our Galaxy moved at a significant speed (close to 600 km/S compared to the surface of last diffusion, probably because of gravitational attraction between our Galaxy and an important concentration of mass located in its vicinity, the Large Attractile.
Participation in COBE
At the time, the cosmological diffuse bottom appeared perfectly uniform, if one excludes the distortion due to the Doppler effect mentioned above. This result was in contradiction with the observation of the current universe which had various structures (Galaxie S, Galaxy cluster, etc) indicating that the universe was with relatively inhomogenous small scales. However the theory of the Formation of the great structures predicts that the structures in the universe are formed slowly. Thus, if the universe has inhomogeneousness today, it was to have inhomogeneousness at the time of the emission of the cosmological diffuse bottom, and those were to be observable today in the form of weak variations in temperature in the cosmological diffuse content. It is towards the detection of these variations in temperatures, as called Anisotropie S, as Smoot is turned then at the end of the Années 1970. He then proposes with NASA a project of satellite equipped with a detector using same technology as that embarked on the U-2 plane, but much more sensitive and being freed from atmospheric pollution. This project was accepted and gave rise to the satellite COBE, of a cost of 160 million dollars. This one was launched the November 18th 1989, after a delay due to the explosion of the Space shuttle Challenger. After more than two years of observation and analysis, the team of satellite COBE in charge of detection with the anisotropies with the cosmological diffuse bottom (instrument DMR), carried out by George Smoot announced the April 23rd 1992 to have detected negligible fluctuations in the cosmological diffuse content, an event unanimously greeted by the scientific world. He reported the adventure of satellite COBE in a work general public the wrinkles of time (see bibliography). It should be noted however that John C. Mather announced difference in opinion certain with George Smoot in another work reporting its version of this adventure This one in particular reproached him its attitude at the time of the advertisement into 1992 of the results obtained by experiment DMR of satellite COBE.
Recent activities
Since the end of mission COBE, George Smoot took part in another experiment assembled on a stratospheric balloon, MAXIMUM, more precise than COBE, which contributed to refine measurements of the anisotropies of the cosmological diffuse bottom. It also forms part of collaboration SNAP, a project of satellite aiming at measuring with precision certain properties of the black energy and works on the data of the Space telescope Spitzer in connection with the infra-red diffuse Fond.