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  • Four direct measurements of...
    Wilczynska, Michael R; Webb, John K; Bainbridge, Matthew; Barrow, John D; Bosman, Sarah E I; Carswell, Robert F; Dąbrowski, Mariusz P; Dumont, Vincent; Lee, Chung-Chi; Leite, Ana Catarina; Leszczyńska, Katarzyna; Liske, Jochen; Marosek, Konrad; Martins, Carlos J A P; Milaković, Dinko; Molaro, Paolo; Pasquini, Luca

    Science advances, 04/2020, Letnik: 6, Številka: 17
    Journal Article

    Observations of the redshift = 7.085 quasar J1120+0641 are used to search for variations of the fine structure constant, a, over the redshift range 5:5 to 7:1. Observations at = 7:1 probe the physics of the universe at only 0.8 billion years old. These are the most distant direct measurements of a to date and the first measurements using a near-IR spectrograph. A new AI analysis method is employed. Four measurements from the x-shooter spectrograph on the Very Large Telescope (VLT) constrain changes in a relative to the terrestrial value (α ). The weighted mean electromagnetic force in this location in the universe deviates from the terrestrial value by Δα/α = (α - α )/α = (-2:18 ± 7:27) × 10 , consistent with no temporal change. Combining these measurements with existing data, we find a spatial variation is preferred over a no-variation model at the 3:9σ level.