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.)