18,876 research outputs found
Promise Arizona: Building Immigrant Political Power
This case study investigates the history and accomplishments of one organization that is making considerable strides in advancing the values and political interests of the Latino community. Beginning in 2010, Promise Arizona (PAZ) and Promise Arizona in Action (PAZ en Acción) work to empower Latinos and the immigrant community to flex their civic muscle through community organizing and political action. This case study provides a snapshot of the organization's formation, growth, and organizing initiatives and explores what strategies have been central to its success. It is one model of how grassroots organizing can contribute to achieving immigration rights
Versal deformation of the Lie algebra
We investigate deformations of the infinite dimensional vector field Lie algebra spanned by the fields , where . The goal is to describe the base of a ``versal'' deformation; such a versal deformation induces all the other nonequivalent deformations and solves the deformation problem completely. \u
How far can Tarzan jump?
The tree-based rope swing is a popular recreation facility, often installed
in outdoor areas, giving pleasure to thrill-seekers. In the setting, one drops
down from a high platform, hanging from a rope, then swings at a great speed
like "Tarzan", and finally jumps ahead to land on the ground. The question now
arises: How far can Tarzan jump by the swing? In this article, I present an
introductory analysis of the Tarzan swing mechanics, a big pendulum-like swing
with Tarzan himself attached as weight. The analysis enables determination of
how farther forward Tarzan can jump using a given swing apparatus. The
discussion is based on elementary mechanics and, therefore, expected to provide
rich opportunities for investigations using analytic and numerical methods.Comment: 8 pages, 4 figure
Soliton surfaces associated with sigma models; differential and algebraic aspect
In this paper, we consider both differential and algebraic properties of
surfaces associated with sigma models. It is shown that surfaces defined by the
generalized Weierstrass formula for immersion for solutions of the CP^{N-1}
sigma model with finite action, defined in the Riemann sphere, are themselves
solutions of the Euler-Lagrange equations for sigma models. On the other hand,
we show that the Euler-Lagrange equations for surfaces immersed in the Lie
algebra su(N), with conformal coordinates, that are extremals of the area
functional subject to a fixed polynomial identity are exactly the
Euler-Lagrange equations for sigma models. In addition to these differential
constraints, the algebraic constraints, in the form of eigenvalues of the
immersion functions, are treated systematically. The spectrum of the immersion
functions, for different dimensions of the model, as well as its symmetry
properties and its transformation under the action of the ladder operators are
discussed. Another approach to the dynamics is given, i.e. description in terms
of the unitary matrix which diagonalizes both the immersion functions and the
projectors constituting the model.Comment: 22 pages, 3 figure
Mobilizing Public Will For Social Change
Examines the theory and strategies of "public will" campaigns and offers tangible criteria for their evaluation. It provides a rich inventory of strategies for use in mobilizing the public will through an integration of models of agenda building, social problem construction, issues management, social movements, media advocacy, and social capital. In addition, the paper provides cases and examples of public will campaigns directed at various social problems, along with criteria for evaluating these campaigns at various stages of a social problem's life cycle
Maxwell's theory on a post-Riemannian spacetime and the equivalence principle
The form of Maxwell's theory is well known in the framework of general
relativity, a fact that is related to the applicability of the principle of
equivalence to electromagnetic phenomena. We pose the question whether this
form changes if torsion and/or nonmetricity fields are allowed for in
spacetime. Starting from the conservation laws of electric charge and magnetic
flux, we recognize that the Maxwell equations themselves remain the same, but
the constitutive law must depend on the metric and, additionally, may depend on
quantities related to torsion and/or nonmetricity. We illustrate our results by
putting an electric charge on top of a spherically symmetric exact solution of
the metric-affine gauge theory of gravity (comprising torsion and
nonmetricity). All this is compared to the recent results of Vandyck.Comment: 9 pages, REVTeX, no figures; minor changes, version to be published
in Class. Quantum Gra
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