3,008 research outputs found

    When Statutory Regimes Collide:Will Wisconsin Right to Life and Citizens United Invalidate Federal Tax Regulation of Campaign Activity?

    Get PDF
    In Federal Election Commission v. Wisconsin Right to Life (2007) and Citizens United v. Federal Elections Commission (2010), the United States Supreme Court dramatically reduced the ability of Congress to regulate campaign finance activities of corporations and others active in elections. Many of the same activities are still subject to restrictions by the Internal Revenue Code, which regulates the type and amount of political campaign activities that certain nonprofits exempt under federal tax law can engage in. In the wake of the campaign finance decisions, the constitutionality of the tax law’s restrictions on campaign activity is now being challenged in the lower courts. This Article analyzes the two recent campaign finance decisions and campaign finance precedents more broadly to determine how, if at all, the Roberts’ Court’s campaign finance jurisprudence is likely to alter existing tax law jurisprudence in the area of campaign activity. It finds that, for the most part, tax law constitutional doctrines have developed independently of other areas of First Amendment free speech law. Based upon an analysis of the distinctive tax law doctrines, the Article concludes that the tax law provision prohibiting section 501(c)(3) charities from engaging in campaigns is likely to withstand challenges arguing that the provision prevents these nonprofits from engaging in protected political speech. However, there is some likelihood that the tax law prohibition is vulnerable to constitutional attack under traditional doctrines of vagueness or overbreadth due to the lack of precision of the terms of the political prohibition, as these have been elaborated by the IRS and the courts to date

    Dynamical Symmetry Breaking in Planar QED

    Get PDF
    We investigate (2+1)-dimensional QED coupled with Dirac fermions both at zero and finite temperature. We discuss in details two-components (P-odd) and four-components (P-even) fermion fields. We focus on P-odd and P-even Dirac fermions in presence of an external constant magnetic field. In the spontaneous generation of the magnetic condensate survives even at infinite temperature. We also discuss the spontaneous generation of fermion mass in presence of an external magnetic field.Comment: 34 pages, 8 postscript figures, final version to appear on J. Phys.

    A cross-border deforestation index to understand underlying drivers of deforestation

    Get PDF
    This paper considers a preliminary investigation involving the development of a Cross-Border Deforestation Index (CBDI), which is an attempt to quantify the differences in deforestation between two countries or potentially any two administrative units. In this study, the focus was on countries. For each pair of bordering countries, a 50km buffer zone was drawn and the average value of the Vegetation Continuous Field (VCF) was calculated for each country in the pair. The ratio of these two averages is the CBDI. Values of 1 indicate similar levels of forest cover but values greater than 1 point towards dissimilar land use policies within countries and/or sub-national administrative levels. This index was calculated for all pairs of bordering tropical countries in South and Central America, Asia and Africa. In addition, a visual analysis of the spatial variation of the VCF was undertaken to show how this can complement the CBDI. The results showed that countries such as Argentina, Brazil, Chile, El Salvador, Laos, Thailand and DR Congo, in combination with different neighbouring countries, all have CBDI values differing from 1. These areas are worth examining in greater detail in order to understand what types of drivers are behind these outlying CBDI values. These drivers could include land use policy, population pressure, accessibility, etc. Future work will i nclude the addition of environmental factors. By computing the CBDI for so called Homogeneous Response Units (HRU: areas of similar or identical environmental conditions in terms of soil, altitude and slope), we will be able to examine the changing effect on the CBDI. This work is still ongoing and will be expanded to consider HRU for all country pairs. In addition, regression of the CBDI with different drivers of deforestation will be attempted in order to help identify these underlying causes

    Analog of Magnetoelectric Effect in High-Tc Granular Superconductors

    Full text link
    We propose the existence of an electric-field induced nonlinear magnetization in a weakly coupled granular superconductor due to time-parity violation. As the field increases the induced magnetization passes from para- to dia-magnetic behavior. We discuss conditions under which this effect could be experimentally measured in high-temperature superconductors.Comment: REVTEX (epsf style), 1 PS figure; to appear in Europhysics Letter

    Network synchronization: Optimal and Pessimal Scale-Free Topologies

    Full text link
    By employing a recently introduced optimization algorithm we explicitely design optimally synchronizable (unweighted) networks for any given scale-free degree distribution. We explore how the optimization process affects degree-degree correlations and observe a generic tendency towards disassortativity. Still, we show that there is not a one-to-one correspondence between synchronizability and disassortativity. On the other hand, we study the nature of optimally un-synchronizable networks, that is, networks whose topology minimizes the range of stability of the synchronous state. The resulting ``pessimal networks'' turn out to have a highly assortative string-like structure. We also derive a rigorous lower bound for the Laplacian eigenvalue ratio controlling synchronizability, which helps understanding the impact of degree correlations on network synchronizability.Comment: 11 pages, 4 figs, submitted to J. Phys. A (proceedings of Complex Networks 2007

    Microscopic Black Hole Pairs in Highly-Excited States

    Get PDF
    We consider the quantum mechanics of a system consisting of two identical, Planck-size Schwarzschild black holes revolving around their common center of mass. We find that even in a very highly-excited state such a system has very sharp, discrete energy eigenstates, and the system performs very rapid transitions from a one stationary state to another. For instance, when the system is in the 100th excited state, the life times of the energy eigenstates are of the order of 103010^{-30} s, and the energies of gravitons released in transitions between nearby states are of the order of 102210^{22} eV.Comment: 22 pages, 3 figures, uses RevTe

    An Exploration of Some Pitfalls of Thematic Map Assessment Using the New Map Tools Resource

    Get PDF
    A variety of metrics are commonly employed by map producers and users to assess and compare thematic maps’ quality, but their use and interpretation is inconsistent. This problem is exacerbated by a shortage of tools to allow easy calculation and comparison of metrics from different maps or as a map’s legend is changed. In this paper, we introduce a new website and a collection of R functions to facilitate map assessment. We apply these tools to illustrate some pitfalls of error metrics and point out existing and newly developed solutions to them. Some of these problems have been previously noted, but all of them are under-appreciated and persist in published literature. We show that binary and categorical metrics, including information about true-negative classifications, are inflated for rare categories, and more robust alternatives should be chosen. Most metrics are useful to compare maps only if their legends are identical. We also demonstrate that combining land-cover classes has the often-neglected consequence of apparent improvement, particularly if the combined classes are easily confused (e.g., different forest types). However, we show that the average mutual information (AMI) of a map is relatively robust to combining classes, and reflects the information that is lost in this process; we also introduce a modified AMI metric that credits only correct classifications. Finally, we introduce a method of evaluating statistical differences in the information content of competing maps, and show that this method is an improvement over other methods in more common use. We end with a series of recommendations for the meaningful use of accuracy metrics by map users and producer

    Cosmic censorship and spherical gravitational collapse with tangential pressure

    Get PDF
    We study the spherical gravitational collapse of a compact object under the approximation that the radial pressure is identically zero, and the tangential pressure is related to the density by a linear equation of state. It turns out that the Einstein equations can be reduced to the solution of an integral for the evolution of the area radius. We show that for positive pressure there is a finite region near the center which necessarily expands outwards, if collapse begins from rest. This region could be surrounded by an inward moving one which could collapse to a singularity - any such singularity will necessarily be covered by a horizon. For negative pressure the entire object collapses inwards, but any singularities that could arise are not naked. Thus the nature of the evolution is very different from that of dust, even when the ratio of pressure to density is infinitesimally small.Comment: 16 pages, Latex file, two figures, uses epsf.st
    corecore