R. R. Phelps

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Introduction. These lectures will focus on those properties of maximal monotone operators which are valid in arbitrary real Banach spaces. Most applications (to nonlinear partial differential equations, optimization, calculus of variations, etc.) take place in reflexive spaces, in part because several key properties have only been shown to hold in such(More)
1. Introduction. If £ is a real normed linear space, a subspace M of E is said to be a CebySev subspace ii to each y in E there exists a unique nearest element x in M, that is, an element x in M such that ||y—x|| <||y—z\\ for zEM, z^x. The problem of characterizing such subspaces for the classical Banach spaces of functions is an interesting one. The first(More)
We report the detection of Cepheids and a new distance to the spiral galaxy NGC 2541, based on data obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope (HST). A total of 25 exposures (divided into 13 epochs) are obtained using the F555W filter (transformed to Johnson V), and nine exposures (divided into five epochs) using(More)
The differentiability properties of the metric projection Pc on a closed convex set C in Hilbert space are characterized in terms of the smoothness type of the boundary of C. Our approach is based on using variational type second derivatives as a sufficiently flexible tool to describe the boundary struc ture of the set C with regard to the differentiability(More)
In an attempt to use Cepheid variables to determine the distance to the Centaurus cluster, we have obtained images of NGC 4603 with the Hubble Space Telescope for 9 epochs (totalling 24 orbits) over 14 months in the F555W filter and 2 epochs (totalling 6 orbits) in the F814W filter. This galaxy has been suggested to lie within the " Cen30 " portion of the(More)
In collaboration with Sneden ͑Univ. of Texas͒, McWilliam and Preston have acquired new high-resolution, high S/N spectra of CS 22892–052 with the CTIO 4-meter telescope and echelle spectrograph. This star is particularly interesting, as it possesses scaled heavy element abundances in excess of 40 times the solar value, with a pure r-process abundance(More)
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