Kramers-Kronig Relations For The Dielectric Function And The Static Conductivity Of Coulomb Systems

The mutual influence of singularities of the dielectric permittivity e(q,w) in a Coulomb system in two limiting cases w tends to zero, q tends to zero, and opposite q tends to zero, w tends to zero is established. It is shown that the dielectric permittivity e(q,w) satisfies the Kramers-Kronig relations, which possesses the singularity due to a finite value of the static conductivity. This singularity is associated with the long "tails" of the time correlation functions.Comment: 9 pages, 0 figure

Matter-field theory of the Casimir force

A matter-field theory of the Casimir force is formulated in which the electromagnetic field and collective modes of dielectric media are treated on an equal footing. In our theory, the Casimir force is attributed to zero-point energies of the combined matter-field modes. We analyze why some of the existing theories favor the interpretation of the Casimir force as originating from zero-point energies of the electromagnetic field and others from those of the matter.Comment: 12pages, 1 Postscript figur

Parity-Violating Electron-Deuteron Scattering

The longitudinal asymmetry due to $Z^0$ exchange is calculated in quasi-elastic electron-deuteron scattering at momentum transfers $|Q^2| \simeq 0.1$ GeV$^2$ relevant for the SAMPLE experiment. The deuteron and $pn$ scattering-state wave functions are obtained from solutions of a Schr\"odinger equation with the Argonne $v_{18}$ potential. Electromagnetic and weak neutral one- and two-nucleon currents are included in the calculation. The two-nucleon currents of pion range are shown to be identical to those derived in Chiral Perturbation Theory. The results indicate that two-body contributions to the asymmetry are small ($\simeq$ 0.2%) around the quasi-elastic peak, but become relatively more significant ($\simeq$ 3%) in the high-energy wing of the quasi-elastic peak.Comment: 23 pages, 10 figure

Managing the Socially Marginalized: Attitudes Towards Welfare, Punishment and Race

Welfare and incarceration policies have converged to form a system of governance over socially marginalized groups, particularly racial minorities. In both of these policy areas, rehabilitative and social support objectives have been replaced with a more punitive and restrictive system. The authors examine the convergence in individual-level attitudes concerning welfare and criminal punishment, using national survey data. The authors\u27 analysis indicates a statistically significant relationship between punitive attitudes toward welfare and punishment. Furthermore, accounting for the respondents\u27 racial attitudes explains the bivariate relationship between welfare and punishment. Thus, racial attitudes seemingly link support for punitive approaches to opposition to welfare expenditures. The authors discuss the implications of this study for welfare and crime control policies by way of the conclusion

Sea otter effects on trophic structure of seagrass communities in southeast Alaska

Previous research in southeast Alaska on the effects of sea otters Enhydra lutris in seagrass Zostera marina communities identified many but not all of the trophic relationships that were predicted by a sea otter-mediated trophic cascade. To further resolve these trophic connections, we compared biomass, carbon (δ13C) and nitrogen (δ15N) stable isotope (SI), and fatty acid (FA) data from 16 taxa at 3 sites with high and 3 sites with low sea otter density (8.2 and 0.1 sea otters km−2, respectively). We found lower crab and clam biomass in the high sea otter region but did not detect a difference in biomass of other seagrass community taxa or the overall community isotopic niche space between sea otter regions. Only staghorn sculpin differed in δ13C between regions, and Fucus, sugar kelp, butter clams, dock shrimp, and shiner perch differed in δ15N. FA analysis indicated multivariate dissimilarity in 11 of the 15 conspecifics between sea otter regions. FA analysis found essential FAs, which consumers must obtain from their diet, including 20:5ω3 (EPA) and 22:6ω3 (DHA), were common in discriminating conspecifics between sea otter regions, suggesting differences in consumer diets. Further FA analysis indicated that many consumers rely on diverse diets, regardless of sea otter region, potentially buffering these consumers from sea otter-mediated changes to diet availability. While sea otters are major consumers in this system, further studies are needed to understand the mechanisms responsible for the differences in biomarkers between regions with and without sea ottersWe thank Tiffany Stephens, Maggie Shields, Melanie Borup, Ashely Bolwerk, Nicole LaRoche, Tom Bell, Michael Stekoll and the rest of the Apex Predators, Ecosystems and Community Sustainability (APECS) team and 26 Earthwatch volunteers for assistance in the field and laboratory. Special thanks to Reyn Yoshioka, Natalie Thompson, the Coastal Trophic Ecology Lab, and Oregon Institute of Marine Biology for their assistance with fatty acid extractions, Melissa Rhodes-Reese at University of Alaska Southeast for water nutrient analysis, and Matthew Rogers and NOAA Auke Bay Laboratories for assistance with stable isotope analyses. This study was funded by the National Science Foundation (NSF #1635716, #1600230 to G.L.E.), through the generous support of Earthwatch, and a 56 NSF Graduate Research Fellowship, a North Pacific Re - search Board Graduate Student Research Award, an American Fisheries Society Steven Berkeley Marine Conservation Fellowship, and a Lerner Gray Memorial Fund (to W.W.R). This study was completed in partial fulfillment of the requirements for W.W.R.’s PhD at the University of Alaska Fairbanks and we thank committee members Dr. Franz Mueter and Dr. Anne Beaudreau for their comments on this project and the manuscript. Finally, we thank the 3 anonymous reviewers whose comments greatly improved the manuscript. This study was conducted on the traditional lands and waters of the Alaska Native Tlingit and Haida peoples. We are grateful for our access to these spaces and benefited from conversations and support from the members of Tribal communities and governments.Ye

ASCR/HEP Exascale Requirements Review Report

This draft report summarizes and details the findings, results, and recommendations derived from the ASCR/HEP Exascale Requirements Review meeting held in June, 2015. The main conclusions are as follows. 1) Larger, more capable computing and data facilities are needed to support HEP science goals in all three frontiers: Energy, Intensity, and Cosmic. The expected scale of the demand at the 2025 timescale is at least two orders of magnitude -- and in some cases greater -- than that available currently. 2) The growth rate of data produced by simulations is overwhelming the current ability, of both facilities and researchers, to store and analyze it. Additional resources and new techniques for data analysis are urgently needed. 3) Data rates and volumes from HEP experimental facilities are also straining the ability to store and analyze large and complex data volumes. Appropriately configured leadership-class facilities can play a transformational role in enabling scientific discovery from these datasets. 4) A close integration of HPC simulation and data analysis will aid greatly in interpreting results from HEP experiments. Such an integration will minimize data movement and facilitate interdependent workflows. 5) Long-range planning between HEP and ASCR will be required to meet HEP's research needs. To best use ASCR HPC resources the experimental HEP program needs a) an established long-term plan for access to ASCR computational and data resources, b) an ability to map workflows onto HPC resources, c) the ability for ASCR facilities to accommodate workflows run by collaborations that can have thousands of individual members, d) to transition codes to the next-generation HPC platforms that will be available at ASCR facilities, e) to build up and train a workforce capable of developing and using simulations and analysis to support HEP scientific research on next-generation systems.Comment: 77 pages, 13 Figures; draft report, subject to further revisio