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Updated: Dec 9, 2025

Sediment Core Extrusion Method at Millimeter Resolution Using a Calibrated, Threaded-rod
Published on: August 17, 2016
Four direct measurements of the fine-structure constant 13 billion years ago
Michael R Wilczynska1, John K Webb2, Matthew Bainbridge3
1University of New South Wales Sydney, Sydney, NSW 2052, Australia.
Abstract:
Observations of the redshift z = 7.085 quasar J1120+0641 are used to search for variations of the fine structure constant, α, over the redshift range 5.5 to 7.1. Observations at z = 7.1 probe the physics of the universe at only 0.8 billion years old. These are the most distant direct measurements of α 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 (α0). The weighted mean electromagnetic force in this location in the universe deviates from the terrestrial value by Δα/α = (α - α0)/α0 = (-2.18 ± 7.27) × 10-5, 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.
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