Appears to be constant after all. In 1999, an analysis of spectra from quasars led researchers to conclude that α, the stalwart of quantum physics, might change slightly over cosmological time (see Physics Today, March 1999, page 9, and October 2001, page 9). But now, Keith Olive (University of Minnesota) and his colleagues have shown that a first generation of highly evolved intermediate-mass stars in quasar absorption systems could change the previously assumed isotopic abundances of magnesium enough to account for the puzzling spectra. Thus, according to Olive, the quasar observations might be teaching us important lessons about the chemical evolution of the universe. (TAshenfelter, G. J.Mathews, K. A.Olive, Phys. Rev. Lett., in press.)
Despite the tumultuous history of the near-Earth object’s parent body, water may have been preserved in the asteroid for about a billion years.
October 08, 2025 08:50 PM
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Physics Today - The Week in Physics
The Week in Physics" is likely a reference to the regular updates or summaries of new physics research, such as those found in publications like Physics Today from AIP Publishing or on news aggregators like Phys.org.