23,919 research outputs found
Electron cyclotron maser emission mode coupling to the z-mode on a longitudinal density gradient in the context of solar type III bursts
Copyright 2012 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Physics of Plasmas 19, 110702 (2012) and may be found at .supplemental material at http://astro.qmul.ac.uk/~tsiklauri/sp.htmlsupplemental material at http://astro.qmul.ac.uk/~tsiklauri/sp.htm
Dynamical N-body Equlibrium in Circular Dilaton Gravity
We obtain a new exact equilibrium solution to the N-body problem in a
one-dimensional relativistic self-gravitating system. It corresponds to an
expanding/contracting spacetime of a circle with N bodies at equal proper
separations from one another around the circle. Our methods are
straightforwardly generalizable to other dilatonic theories of gravity, and
provide a new class of solutions to further the study of (relativistic)
one-dimensional self-gravitating systems.Comment: 4 pages, latex, reference added, minor changes in wordin
Consequences of Leading-Logarithm Summation for the Radiative Breakdown of Standard-Model Electroweak Symmetry
In the empirically sensible limit in which QCD, t-quark Yukawa, and
scalar-field-interaction coupling constants dominate all other Standard-Model
coupling constants, we sum all leading-logarithm terms within the perturbative
expansion for the effective potential that contribute to the extraction of the
Higgs boson mass via radiative electroweak symmetry breaking. A Higgs boson
mass of 216 GeV emerges from such terms, as well as a scalar-field-interaction
coupling constant substantially larger than that anticipated from conventional
spontaneous symmetry breaking. The sum of the effective potential's leading
logarithms is shown to exhibit a local minimum in the limit if the
QCD coupling constant is sufficiently strong, suggesting (in a multiphase
scenario) that electroweak physics may provide the mechanism for choosing the
asymptotically-free phase of QCD.Comment: latex using aip proceedings class. 8 page write-out of presentation
at MRST 2003 Conference (Syracuse
Symmetry Breaking Using Value Precedence
We present a comprehensive study of the use of value precedence constraints
to break value symmetry. We first give a simple encoding of value precedence
into ternary constraints that is both efficient and effective at breaking
symmetry. We then extend value precedence to deal with a number of
generalizations like wreath value and partial interchangeability. We also show
that value precedence is closely related to lexicographical ordering. Finally,
we consider the interaction between value precedence and symmetry breaking
constraints for variable symmetries.Comment: 17th European Conference on Artificial Intelligenc
The effect of electron beam pitch angle and density gradient on solar type III radio bursts
Copyright 2012 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. This article appeared in Physics of Plasmas 19, 112903 (2012) and may be found at .supplemental material at http://astro.qmul.ac.uk/~tsiklauri/sp.htmlsupplemental material at http://astro.qmul.ac.uk/~tsiklauri/sp.htm
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Dietary manipulation of broiler breeder growth through the feeding of conjugated linoleic acid
New Types of Thermodynamics from -Dimensional Black Holes
For normal thermodynamic systems superadditivity , homogeneity \H and
concavity \C of the entropy hold, whereas for -dimensional black holes
the latter two properties are violated. We show that -dimensional black
holes exhibit qualitatively new types of thermodynamic behaviour, discussed
here for the first time, in which \C always holds, \H is always violated
and may or may not be violated, depending of the magnitude of the black
hole mass. Hence it is now seen that neither superadditivity nor concavity
encapsulate the meaning of the second law in all situations.Comment: WATPHYS-TH93/05, Latex, 10 pgs. 1 figure (available on request), to
appear in Class. Quant. Gra
Soliton Solutions to the Einstein Equations in Five Dimensions
We present a new class of solutions in odd dimensions to Einstein's equations
containing either a positive or negative cosmological constant. These solutions
resemble the even-dimensional Eguchi-Hanson--(anti)-de Sitter ((A)dS) metrics,
with the added feature of having Lorentzian signatures. They provide an
affirmative answer to the open question as to whether or not there exist
solutions with negative cosmological constant that asymptotically approach
AdS, but have less energy than AdS. We present
evidence that these solutions are the lowest-energy states within their
asymptotic class.Comment: 9 pages, Latex; Final version that appeared in Phys. Rev. Lett; title
changed by journal from original title "Eguchi-Hanson Solitons
Kindergarten Dinosaurs and Rocks: An Example of Integrating a Field-tested Lesson Plan for Geoscientists into the Alberta Curriculum
Professional geoscientists have to make many presentations to colleagues, engineers, executives and accountants. However, panic is often felt when a note comes home from a child's educator looking for parents to help in teaching elementary school students. For the teacher, this is a chance to integrate many core subjects from the curriculum with the special and exciting resources available to geoscientists. This paper presents guidelines developed over time, and includes an understanding of how children learn and ask questions, the pace of the talk, and what children need to learn. In addition, data sources and gateways available to geoscientists have been included. While the premise outlined in the paper is applicable across Canada, it is based on the Alberta curriculum requirements. With these suggestions, the classroom experience is really no different than presenting to senior management, although you have to remember that your audience is shorter and does not drive a big BMW or Lexus.
RÉSUMÉ
Les géoscientifiques ont souvent à faire des exposés à des collègues, des ingénieurs, des dirigeants et des comptables. Cela dit, il arrive souvent qu'un sentiment de panique s'empare d'eux lorsqu'ils reçoivent une note des enseignants du primaire aux parents faisant appel aux compétences professionnelles des parents. Les enseignants y voient là une occasion de lier les thèmes du programme d'enseignement aux ressources fantastiques dont disposent les géoscientifiques. Le présent article présente les lignes directrices qui ont été validées avec le temps et décrit les modes d'apprentissage des enfants, leurs manières de poser des questions, le rythme particulier de présentation, ainsi que ce qu'ils ont besoin d'apprendre. L'article comporte aussi des références à des sources et des passerelles de données que les géoscientifiques peuvent consulter. Les principes de base présentés dans cet article peuvent s'appliquer partout à travers le pays, simplement, on les a appliqués aux exigences particulières du programme scolaire de l'Alberta. En tenant compte des suggestions offertes, on se rendra compte qu'une classe d'école n'est pas différente d'une d'un auditoire de gestionnaires; il faut simplement se souvenir que les membres de l'auditoire sont plus courts et ne conduisent pas des BM ou des Lexus
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