1,858 research outputs found
Parity violation and the mean field approximation for the anyon gas
We examine an approach to justifying the mean field approximation for the
anyon gas, using the scattering of anyons. Parity violation permits a nonzero
average scattering angle, from which one can extract a mean radius of curvature
for anyons. If this is larger than the interparticle separation, one expects
that the graininess of the statistical magnetic field is unimportant, and that
the mean field approximation is good. We argue that a non-conventional
interaction between anyons is crucial, in which case the criterion for validity
of the approximation is identical to the one deduced using a self-consistency
argument.Comment: 11 pages, UdeM-LPN-TH-13
Gill Ventilation Rates of Mayfly Nymphs (Ephemeroptera: Heptageniidae) as a Biomonitoring Technique
Gill ventilation frequency (GVF) of the mayfly nymph Stenacron interpunctatum (Ephemeroptera: Heptageniidae) was studied to assess the applicability of a relatively simple, real time video methodology and to assess the potential of GVF rates for use in a chronic assay of sediment pore water. Stenacron interpunctatum nymphs were exposed to pore water samples taken along a transect from the mouth of the Fox River to Sturgeon Bay in the Green Bay area of Lake Michigan. This transect has previously been shown to exhibit several distinct gradients in sediment and water column conditions with distance from the Fox River. The highest GVF value of 6.68 ± 0.27 Hz was observed in pore water from the more polluted area near the Fox River. A lower GVF value of 5.44 ± 0.32 Hz was observed in pore water from the station near Sturgeon Bay and of 4.25 ± 0.27 Hz from the cleaner Lake Michigan station. GVF values exhibited a decreasing trend with relative distance from the mouth of the Fox River (r2 = 0.76)
A Preservative-Free Emergent Trap for the Isotopic and Elemental Analysis of Emergent Insects From a Wetland System
This study reports a cost-effective, live emergent trap designed for the preservative-free use in both biogeochemical and ecological analyses of emerging insects. The trap proved to be advantageous in several ways. First, the simple design made the trap time-efficient since it was easy to set-up, change, and maintain. Second, live sampling not only provided uncontaminated organisms for elemental and stable isotopic analyses, it minimized disfigurement. This resulted in rapid and easy handling, as well as identification, of adult insects. Finally, trap avoidance by ephemeropterans and odonates, a common problem encountered in the literature, was minimal and organisms from both insect orders were successfully collected
Tunneling decay of false domain walls: the silence of the lambs
We study the decay of "false” domain walls, which are metastable states of the quantum theory where the true vacuum is trapped inside the wall, with the false vacuum outside. We consider a theory with two scalar fields, a shepherd field and a field of sheep. The shepherd field serves to herd the solitons of the sheep field so that they are nicely bunched together. However, quantum tunnelling of the shepherd field releases the sheep to spread out uncontrollably. We show how to calculate the tunnelling amplitude for such a disintegration
Lattice QCD Application Development within the US DOE Exascale Computing Project
In October, 2016, the US Department of Energy launched the Exascale Computing
Project, which aims to deploy exascale computing resources for science and
engineering in the early 2020's. The project brings together application teams,
software developers, and hardware vendors in order to realize this goal.
Lattice QCD is one of the applications. Members of the US lattice gauge theory
community with significant collaborators abroad are developing algorithms and
software for exascale lattice QCD calculations. We give a short description of
the project, our activities, and our plans.Comment: 35th International Symposium on Lattice Field Theory (Lattice 2017
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