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Physics News Update
Number 342 (Story #2), October 22, 1997 by Phillip F. Schewe and Ben Stein

HIGH-PRECISION COSMOLOGY will be possible in the next few years through new measurements of the cosmic microwave background (CMB)---with NASA's MAP satellite and the European's Planck satellites---and expanded catalogs of galaxy locations with the Sloan Digital Sky Survey (a million redshifts to be recorded in 5 years). Several years ago the COBE satellite took the temperature of the universe; the new CMB and galaxy studies should go far to "weigh" the universe and determine whether it will expand forever or collapse. Actually, the universe's vitae are expressed more scientifically in terms of parameters such as omega (energy density), lambda (cosmological constant), and H (Hubble constant). Max Tegmark of the Institute for Advanced Study (max@ias.edu) has estimated the effect of the new data on each of these parameters. For example, big blobs in the CMB map imply a large value for omega, which in turn suggests the universe will collapse. Small blobs imply a smaller omega and an expanding universe. Higher resolution samplings of tiny portions of the CMB, such as that made with the Saskatoon detector in northern Canada, observe blobs at a size that stands midway between that corresponding to an open and shut universe. The new data should settle the matter. (Tegmark,in Physical Review Letters, tent. 3 Nov.; see figure at Physics News Graphics)