THE DANGERS OF FIGHTING TERRORISM WITH TECHNOCOMMUNITARIANISM: CONSTITUTIONAL PROTECTIONS OF FREE EXPRESSION, EXPLORATION, AND UNMONITORED ACTIVITY IN URBAN SPACES

Part I of this article examines how some commentators can plausibly argue that constitutional liberty and privacy protections do not protect the individual liberty and privacy that modern individuals have come to expect in many public spaces, particularly in urban environments. Constitutional liberalism, this section points out, makes this question a difficult one, because it is marked by scrupulous neutrality towards different visions of “the good life.” In other words, the constitutional order does not condemn those who choose a communitarian way of life and favor those who prefer individualism. Rather, it tolerates both of these (and other) preferences about one’s social and cultural environment, and leaves citizens free to opt for the life of their choice. Part II suggests that it is difficult to make sense of our modern jurisprudence of First Amendment rights, especially as they relate to anonymous communication and association on the Internet and elsewhere, unless one allows room in our constitutional law for a jurisprudence that “captures” and preserves social incarnations of liberty and privacy that were not yet in existence when theConstitution was drafted. Therefore, it is possible for for courts and others to find that freedom-enabling institutions that did not exist earlier in American history, and might cease to exist in the future, deserve certain constitutional protection while they are here. Part III explains that like the virtual liberation offered by the Internet, city life offered and continues to offer an invaluable refuge for substantial expressive activity and intellectual exploration that would be far more elusive without this type of urban existence. It provides individuals with an incredibly rich bazaar of ideas, and allows them to browse among these deas, substantially free from outside monitoring or control. While First Amendment law does not single out urban environments for protection, it protects such environments indirectly by preserving certain opportunities that are characteristic of modern urban life: opportunities for giving speeches to large crowds, for confronting strangers with ideas they may find unfamiliar or provocative, or for speaking or gathering information in the anonymity of the crowd

Fringe Field Effects on Bending Magnets, Derived for TRANSPORT/TURTLE

A realistic magnetic dipole has complex effects on a charged particle near the entrance and exit of the magnet, even with a constant and uniform magnetic field deep within the interior of the magnet. To satisfy Maxwell's equations, the field lines near either end of a realistic magnet are significantly more complicated, yielding non-trivial forces. The effects of this fringe field are calculated to first order, applying both the paraxial and thin lens approximations. We find that, in addition to zeroth order effects, the position of a particle directly impacts the forces in the horizontal and vertical directions.Comment: 24 pages, 12 figure

CO, HI, recent Spitzer SAGE results in the Large Magellanic Cloud

Formation of GMCs is one of the most crucial issues in galaxy evolution. I will compare CO and HI in the LMC in 3 dimensional space for the first time aiming at revealing the physical connection between GMCs and associated HI gas at a ~40 pc scale. The present major findings are 1) [total CO intensity] [total HI intensity]0.8 for the 110 GMCs, and 2) the HI intensity tends to increase with the evolution of GMCs. I argue that these findings are consistent with the growth of GMCs via HI accretion over a time scale of a few x 10 Myrs. I will also discuss the role of the background stellar gravity and the dynamical compression by supershells in formation of GMCs

High Resolution BIMA Observations of CO, HCN, and 13CO in NGC 1068

We present high-resolution CO, HCN, and 13CO maps of the inner arcminute of NGC 1068 made with the BIMA interferometer. Several features appear in the CO map which have not previously been observed: (1) a firm detection of CO line emission from a compact region centered on the nucleus of the galaxy; (2) the detection of a triplet velocity structure characteristic of kinematically independent regions shown on the spectrum of the unresolved nuclear emission ; and (3) the detection of a molecular bar, the extent and position angle of which are in good agreement with the 2 $\mu$m stellar bar. The most intense CO emission is nonnuclear; the structure and kinematics of this emission imply that this gas is distributed along the inner spiral arms and not in a ring. The bar's kinematic influence on the molecular gas in the spiral arms is modest, with typical ordered noncircular motions of \la\ 30 \kms\ in the plane of the galaxy. Interior to the spiral arms, the bar's influence is more dramatic, as reflected by the twisted isovelocity contours in the CO and HCN velocity fields. The surface density of molecular gas within the central 100 pc radius of NGC 1068 is the same as that in the central 200 pc radius in the Milky Way to within the uncertainties. There is evidence for an $m= 1$ kinematic mode in NGC 1068; we find the kinematic center of rotation to be displaced from the radio continuum center by about 2.9", or 200 pc. The HCN image, in contrast to the CO map, shows a strong concentration of emission centered on the nucleus. The ratio of integrated intensities of the HCN emission to that of CO is about 0.6 and is the highest ratio measured in the central region of any galaxy.Comment: 35 pages of uuencoded, compressed postscript, 20 postscript figures not included but available from [email protected] or from ftp://astro.astro.umd.edu/pub/thelfer/n1068_figs.ps.Z To appear in The Astrophysical Journal, V. 450, Sept. 199

Angular Momentum in Giant Molecular Clouds. I. The Milky Way

We present a detailed analysis comparing the velocity fields in molecular clouds and the atomic gas that surrounds them in order to address the origin of the gradients. To that end, we present first-moment intensity-weighted velocity maps of the molecular clouds and surrounding atomic gas. The maps are made from high-resolution 13CO observations and 21-cm observations from the Leiden/Argentine/Bonn Galactic HI Survey. We find that (i) the atomic gas associated with each molecular cloud has a substantial velocity gradient---ranging within 0.02 to 0.07 km/s/pc---whether or not the molecular cloud itself has a substantial linear gradient (ii) If the gradients in the molecular and atomic gas were due to rotation, this would imply that the molecular clouds have less specific angular momentum than the surrounding HI by a factor of 1-6. (iii) Most importantly, the velocity gradient position angles in the molecular and atomic gas are generally widely separated---by as much as 130 degrees in the case of the Rosette Molecular Cloud. This result argues against the hypothesis that molecular clouds formed by simple top-down collapse from atomic gas.Comment: Accepted for Publication in Ap