Ars Technica: Some theories about the nature and history of the universe suggest that certain physical constants have varied in value over time. Observations of light from a galaxy 7 billion light-years away have shown that one of those constants has not changed for at least the past 7 billion years. The light that was observed showed methanol absorption lines that differed from Earth absorption lines by only 1 part in 10 million. Methanol’s chemical structure is heavily dependent on the ratio of proton mass to electron mass. If that ratio, which is considered one of the fundamental universal constants, had been different 7 billion years ago, then the absorption lines would have been significantly different. Although the observation doesn’t explain why the physical constants have the values they doâmdash;the fine-tuning calculationsâmdash;it does help confirm that physical constants don’t vary in time or space.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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