98 research outputs found
Canonical wave packets in quantum cosmology
We discuss the construction of wave packets resulting from the solutions of a
class of Wheeler-DeWitt equations in Robertson-Walker type cosmologies, for
arbitrary curvature. We show that there always exists a ``canonical initial
slope" for a given initial wave function, which optimizes some desirable
properties of the resulting wave packet, most importantly good
classical-quantum correspondence. This can be properly denoted as a canonical
wave packet. We introduce a general method for finding these canonical initial
slopes which is generalization of our earlier work.Comment: 19 pages, 8 figure
Fractionation of lymphocyte populations with monoclonal antibodies specific for lyt-2.2 And lyt-3.1.
THE INTERSTELLAR DETECTION OF HSCN IN Sgr B2(N)
Author Institution: Department of Chemistry, Department of Astronomy, and Steward Observatory, University of Arizona, Tucson, AZ 85721; Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, and School of Engineering \& Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138HSCN (thiocyanic acid), an energetic isomer of the well-known species HNCS, has been detected toward Sgr B2(N) with the Arizona Radio Observatory 12m telescope. Eight rotational transitions in the K = 0 ladder were observed in the 2mm and 3mm bands. Five consecutive transitions in the 3 mm band are unblended, but three in the 2 mm band are partially masked by lines of other molecules. The line width and radial velocity of HSCN match closely with those of the ground state isomer HNCS, HNCO, and HOCN. Although HSCN is calculated to lie over 3000 K higher in energy than HNCS, its column density of 1.3x10 cm in Sgr B2(N) is only three times lower than that of HNCS. By analogy with the isomeric pair HCN and HNC, these two sulfur-bearing isomers are plausibly formed from a common cation precursor
Challenges of diagnosis and management of axial spondyloarthritis in North Africa and the Middle East: An expert consensus
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