Feynman path-integral approach to the QED3 theory of the pseudogap

In this work the connection between vortex condensation in a d-wave superconductor and the QED$_3$ gauge theory of the pseudogap is elucidated. The approach taken circumvents the use of the standard Franz-Tesanovic gauge transformation, borrowing ideas from the path-integral analysis of the Aharonov-Bohm problem. An essential feature of this approach is that gauge-transformations which are prohibited on a particular multiply-connected manifold (e.g. a superconductor with vortices) can be successfully performed on the universal covering space associated with that manifold.Comment: 15 pages, 1 Figure. Int. J. Mod. Phys. B 17, 4509 (2003). Minor changes from previous versio

Assessment of Effectiveness of Buffer Zones in Removing Impurities in Runoff from Areas Treated with Poultry Litter. Part II: Source Areas to Buffer Areas Ratio Effects

Vegetative filter strips (VFS) are known to reduce runoff losses of nutrients. solids. and other materials from land areas treated with fertilizers . Although VFS effectiveness is known to depend partially on the relative lengths of filter and pollutant source areas. there is little experimental evidence available to quantify this dependence. This is particularly the case when VFS are implemented down-slope of pasture areas treated with animal manures such as poultry litter. This study assessed the influences of pollutant source area (treated with poultry litter) and VFS lengths on VFS removal of total Kjeldahl nitrogen (TKN). ammonia nitrogen (NH3 -N ). nitrate nitrogen (N03-N). ortho-phosphorus (P04-P). total phosphorus (TP). total organic carbon (TOC). total suspended solids (TSS). and fecal coliform (FC) fromincoming runoff for a silt loam soil with fescue cover. Litter-treated lengths of 6.1. 12.2. and 18.3 m with corresponding VFS lengths of up to 18.3 m. 12.2 m. and 6.1 m. respectively, were examined. Runoff was produced from simulated rainfall applied at 50 mm/h for 1 h of runoff. Concentrations of the parameters analyzed were unaffected by litter treated length but demonstrated a first-order decrease with increasing VFS length except in the cases of TSS and FC. Mass transport of TKN. NH3-N. P04-P. and TP increased with increasing litter-treated length (due to increased runoff) and decreased (approximately first-order) with increasing VFS length. Effectiveness of the VFS in terms of TKN. NH3-N. P04 -P. and TP removal from runoff ranged from 6.5 to 96.3% depending on the particular parameter. litter-treated length. and VFS length. The data collected during this study can be helpful in developing and testing simulation models of VFS performance and can thus aid in design of VFS for pasture areas treated with poultry litter

Interdistrict Choice and Teacher Beliefs: Implications for Educational Expectations, Equity, and Policymaking

Interdistrict choice, which allows families to choose between schools outside of their districts of residence, is currently serving more students than any other choice program in the United States. Yet, despite this popularity, there is a pressing need for more research on how interdistrict choice may affect educational equity within U.S. public schools. Drawing on the analytic framework of educational racial contract, this study examines the issue of teacher beliefs in the context of interdistrict choice at a large, urban high school in Arizona, where market-based school choice programs have been continually expanded for nearly three decades. Data were collected through a survey of 112 teachers, who rated their in- district and out-of-district students based on their perception of three developmental skill categories: 1) academic, 2) communication, and 3) behavior. Results speak to negative teacher beliefs about the educability of Students of Color and hold significant implications for teachers’ academic expectations, educational equity, and future policy decisions

Searching for Oscillations in the Primordial Power Spectrum: Perturbative Approach (Paper I)

In this first of two papers, we present a new method for searching for oscillatory features in the primordial power spectrum. A wide variety of models predict these features in one of two different flavors: logarithmically spaced oscillations and linearly spaced oscillations. The proposed method treats the oscillations as perturbations on top of the scale-invariant power spectrum, allowing us to vary all cosmological parameters. This perturbative approach reduces the computational requirements for the search as the transfer functions and their derivatives can be precomputed. We show that the most significant degeneracy in the analysis is between the distance to last scattering and the overall amplitude at low frequencies. For models with logarithmic oscillations, this degeneracy leads to an uncertainty in the phase. For linear spaced oscillations, it affects the frequency of the oscillations. In this first of two papers, we test our code on simulated Planck-like data, and show we are able to recover fiducial input oscillations with an amplitude of a few times order 10^{-2}. We apply the code to WMAP9-year data and confirm the existence of two intriguing resonant frequencies for log spaced oscillations. For linear spaced oscillations we find a single resonance peak. We use numerical simulations to assess the significance of these features and conclude that the data do not provide compelling evidence for the existence of oscillatory features in the primordial spectrum.Comment: 13 pages, 22 figures. Paper 1 of 2. Fixed typos, added reference