U.S. v. Microsoft: Did Consumers Win?

U.S. v. Microsoft and the related state suit filed in 1998 appear finally to have concluded. In a unanimous en banc decision issued in late June 2004, the D.C. Circuit Court of Appeals rejected challenges to the remedies approved by the District Court in November 2002. The wave of follow-on private antitrust suits filed against Microsoft also appears to be subsiding. In this paper we review the remedies imposed in the United States, in terms of both their relationship to the violations found and their impact on consumer welfare. We conclude that the remedies addressed the violations ultimately found by the Court of Appeals (which were a subset of those found by the original district court and an even smaller subset of the violations alleged, both in court and in public discourse) and went beyond them in important ways. Thus, for those who believe that the courts were right in finding that some of Microsoft's actions harmed competition, the constraints placed on its behavior and the active, ongoing oversight by the Court and the plaintiffs provide useful protection against a recurrence of such harm. For those who believe that Microsoft should not have been found liable because of insufficient evidence of harm to consumers, the remedies may be unnecessary, but they avoided the serious potential damage to consumer welfare that was likely to accompany the main alternative proposals. The remedies actually imposed appear to have struck a reasonable balance between protecting consumers against the types of actions found illegal and harming consumers by unnecessarily restricting Microsoft's ability to compete.

Momentum flow in black-hole binaries. I. Post-Newtonian analysis of the inspiral and spin-induced bobbing

A brief overview is presented of a new Caltech/Cornell research program that is exploring the nonlinear dynamics of curved spacetime in binary black-hole collisions and mergers, and of an initial project in this program aimed at elucidating the flow of linear momentum in binary black holes (BBHs). The “gauge-dependence” (arbitrariness) in the localization of linear momentum in BBHs is discussed, along with the hope that the qualitative behavior of linear momentum will be gauge-independent. Harmonic coordinates are suggested as a possibly preferred foundation for fixing the gauge associated with linear momentum. For a BBH or other compact binary, the Landau-Lifshitz formalism is used to define the momenta of the binary’s individual bodies in terms of integrals over the bodies’ surfaces or interiors, and define the momentum of the gravitational field (spacetime curvature) outside the bodies as a volume integral over the field’s momentum density. These definitions will be used in subsequent papers that explore the internal nonlinear dynamics of BBHs via numerical relativity. This formalism is then used, in the 1.5 post-Newtonian approximation, to explore momentum flow between a binary’s bodies and its gravitational field during the binary’s orbital inspiral. Special attention is paid to momentum flow and conservation associated with synchronous spin-induced bobbing of the black holes, in the so-called “extreme-kick configuration” (where two identical black holes have their spins lying in their orbital plane and antialigned)

Effect of regrouping unfamiliar pigs at weaning on immune function

Pigs weaned at 3 weeks of age and regrouped with unfamiliar individuals had a 4-fold increase in plasma cortisol when compared to pigs that remained in a litter group. However, cellular measures of immune function were not altered by regrouping.; Swine Day, Manhattan, KS, November 10, 198

TGCat, The Chandra Transmission Grating Catalog and Archive: Systems, Desgin and Accessibility

The recently released Chandra Transmission Grating Catalog and Archive, TGCat, presents a fully dynamic on-line catalog allowing users to browse and categorize Chandra gratings observations quickly and easily, generate custom plots of resulting response corrected spectra on-line without the need for special software and to download analysis ready products from multiple observations in one convenient operation. TGCat has been registered as a VO resource with the NVO providing direct access to the catalogs interface. The catalog is supported by a back-end designed to automatically fetch newly public data, process, archive and catalog them, At the same time utilizing an advanced queue system integrated into the archive's MySQL database allowing large processing projects to take advantage of an unlimited number of CPUs across a network for rapid completion. A unique feature of the catalog is that all of the high level functions used to retrieve inputs from the Chandra archive and to generate the final data products are available to the user in an ISIS written library with detailed documentation. Here we present a structural overview of the Systems, Design, and Accessibility features of the catalog and archive.United States. National Aeronautics and Space Administration (Chandra X-ray Center (CXC) NASA contract NAS8-03060)United States. National Aeronautics and Space Administration (Smithsonian Astrophysical Observatory (SAO) contract SV3-73016 for the Chandra X-Ray Center and Science Instruments

Visualizing Spacetime Curvature via Frame-Drag Vortexes and Tidal Tendexes II. Stationary Black Holes

When one splits spacetime into space plus time, the Weyl curvature tensor (which equals the Riemann tensor in vacuum) splits into two spatial, symmetric, traceless tensors: the tidal field $E$, which produces tidal forces, and the frame-drag field $B$, which produces differential frame dragging. In recent papers, we and colleagues have introduced ways to visualize these two fields: tidal tendex lines (integral curves of the three eigenvector fields of $E$) and their tendicities (eigenvalues of these eigenvector fields); and the corresponding entities for the frame-drag field: frame-drag vortex lines and their vorticities. These entities fully characterize the vacuum Riemann tensor. In this paper, we compute and depict the tendex and vortex lines, and their tendicities and vorticities, outside the horizons of stationary (Schwarzschild and Kerr) black holes; and we introduce and depict the black holes' horizon tendicity and vorticity (the normal-normal components of $E$ and $B$ on the horizon). For Schwarzschild and Kerr black holes, the horizon tendicity is proportional to the horizon's intrinsic scalar curvature, and the horizon vorticity is proportional to an extrinsic scalar curvature. We show that, for horizon-penetrating time slices, all these entities ($E$, $B$, the tendex lines and vortex lines, the lines' tendicities and vorticities, and the horizon tendicities and vorticities) are affected only weakly by changes of slicing and changes of spatial coordinates, within those slicing and coordinate choices that are commonly used for black holes. [Abstract is abbreviated.]Comment: 19 pages, 7 figures, v2: Changed to reflect published version (changes made to color scales in Figs 5, 6, and 7 for consistent conventions). v3: Fixed Ref

Probing Wolf-Rayet Winds: Chandra/HETG X-Ray Spectra of WR 6

With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding spherical wind of high X-ray-continuum optical depth. The presence of strong helium-like forbidden lines places the source of X-ray emission at tens to hundreds of stellar radii from the photosphere. Variability was present in X-rays and simultaneous optical photometry, but neither were correlated with the known period of the system or with each other. An enhanced abundance of sodium revealed nuclear processed material, a quantity related to the evolutionary state of the star. The characterization of the extent and nature of the hot plasma in WR 6 will help to pave the way to a more fundamental theoretical understanding of the winds and evolution of massive stars.Comment: Accepted by the Astrophysical Journa