701 research outputs found
The Polarisation Signatures of Microlensing
It has already been shown that microlensing can give rise to a non-zero
variable polarisation signal. Here we use realistic simulations to demonstrate
the additional information that can be gained from polarimetric observations of
lensing events.Comment: 4 pages, LaTeX, 2 figures from 6 postscript files. Uses elsart.sty,
graphicx.sty and harvard.sty. To appear in New Astronomy Reviews -
proceedings of the Oxford Workshop `Gravitational Lensing: Nature's Own
Weighing Scales
Pathological effects of an ectoparasitic nematode Noctuidonema guyanense (Nematoda : Aphelenchoididae) on adults of the fall armyworm (Lepidoptera : Noctuidae)
Host range of Noctuidonema guyanense (Nematoda : Aphelenchoididae) : an ectoparasite of moths in French Guiana
Two-Component Scaling near the Metal-Insulator Bifurcation in Two-Dimensions
We consider a two-component scaling picture for the resistivity of
two-dimensional (2D) weakly disordered interacting electron systems at low
temperature with the aim of describing both the vicinity of the bifurcation and
the low resistance metallic regime in the same framework. We contrast the
essential features of one-component and two-component scaling theories. We
discuss why the conventional lowest order renormalization group equations do
not show a bifurcation in 2D, and a semi-empirical extension is proposed which
does lead to bifurcation. Parameters, including the product , are
determined by least squares fitting to experimental data. An excellent
description is obtained for the temperature and density dependence of the
resistance of silicon close to the separatrix. Implications of this
two-component scaling picture for a quantum critical point are discussed.Comment: 7 pages, 1 figur
Working with Northern Communities to Build Collaborative Research Partnerships: Perspectives from Early Career Researchers
Regional Environmental Change: Human Action and Adaptation. What does it take to meet the Belmont challenge?
Schwinger-Keldysh Approach to Disordered and Interacting Electron Systems: Derivation of Finkelstein's Renormalization Group Equations
We develop a dynamical approach based on the Schwinger-Keldysh formalism to
derive a field-theoretic description of disordered and interacting electron
systems. We calculate within this formalism the perturbative RG equations for
interacting electrons expanded around a diffusive Fermi liquid fixed point, as
obtained originally by Finkelstein using replicas. The major simplifying
feature of this approach, as compared to Finkelstein's is that instead of replicas, we only need to consider N=2 species. We compare the dynamical
Schwinger-Keldysh approach and the replica methods, and we present a simple and
pedagogical RG procedure to obtain Finkelstein's RG equations.Comment: 22 pages, 14 figure
Two-Dimensional Wigner Crystal in Anisotropic Semiconductor
We investigate the effect of mass anisotropy on the Wigner crystallization
transition in a two-dimensional (2D) electron gas. The static and dynamical
properties of a 2D Wigner crystal have been calculated for arbitrary 2D Bravais
lattices in the presence of anisotropic mass, as may be obtainable in Si
MOSFETs with (110) surface. By studying the stability of all possible lattices,
we find significant change in the crystal structure and melting density of the
electron lattice with the lowest ground state energy.Comment: 4 pages, revtex, 4 figure
Мультипарадигмальний підхід до аналізу феномену нігілізму
У статті розглянуто нігілізм як неоднозначне й поліморфне поняття. Досліджено різні підходи до
тлумачення та розв’язання питань, пов’язаних із нігілізмом. Розкрито людиномірність нігілізму в контексті
відстеження варіативного смислового навантаження феномену. Встановлено, що нігілізм потрібно
позиціонувати як спосіб пробудження людського духу, заперечення деструктивного конформізму й
відсутності опору (пасивний песимізм).В статье рассмотрен нигилизм как неоднозначное и полиморфное понятие. Исследованы различные подходы
к толкованию и решению вопросов, связанных с нигилизмом. Раскрыта человекомерность нигилизма
в контексте отслеживания вариативной смысловой нагрузки феномена. Установлено, что нигилизм нужно
позиционировать как способ пробуждения человеческого духа, отрицание деструктивного конформизма и
отсутствия сопротивления (пассивный пессимизм).Nihilism is considered as ambiguous and polymorphic concept. Different approaches to the interpretation and solution of
issues associated with nihilism are investigated. Human measurement of nihilism in the context of tracking meaning of
varied semantic capacity of the phenomenon is revealed. It is determined that nihilism must be positioned as a way of
awakening of the human spirit, denial of destructive conformism and absence of resistance (passive pessimism)
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