5,915 research outputs found
A Community\u27s Collective Courage: A Local Food Cooperative\u27s Impact on Food Insecurity, Community and Economic Development, and Local Food Systems
According to the USDAâs âFood Security Status of U.S. Householdsâ in 2014, 48.1 million people live in food insecure households. In Indiana, more than 1 million people suffer from food insecurity with rates as high as 19.2% of Marion Countyâs population according to the Map the Meal Gap 2014 report. The Community Controlled Food Initiative (CCFI) is a local food cooperative operated by the Kheprw Institute and neighborhood residents in the Mid-North Indianapolis Community. The cooperative formed to address food insecurity in August 2015 in response to the closing on the local Double 8 Foods grocery stores. CCFI hosts a monthly food share distribution where residents buy into the program and receive a share of locally sourced fruits and vegetables. The cooperative model is a long tradition of people coming together to address a need in their community or society through a communal business structure. The community lived with food insecurity long before the closing of the grocery stores and decided to take action. This research is a case study using participatory observation testing CCFIâs cooperative model to Jessica Nemhardâs research in Collective Courage: An African American Cooperative History and through the three pillars of impact: addressing food insecurity, community and economic development, and climate change. CCFIâs work shows that food is not only a necessity for life, but also a catalyst for social change
Interacting vector fields in Relativity without Relativity
Barbour, Foster and \'{O} Murchadha have recently developed a new framework,
called here {\it{the 3-space approach}}, for the formulation of classical
bosonic dynamics. Neither time nor a locally Minkowskian structure of spacetime
are presupposed. Both arise as emergent features of the world from
geodesic-type dynamics on a space of 3-dimensional metric--matter
configurations. In fact gravity, the universal light cone and Abelian gauge
theory minimally coupled to gravity all arise naturally through a single common
mechanism. It yields relativity -- and more -- without presupposing relativity.
This paper completes the recovery of the presently known bosonic sector within
the 3-space approach. We show, for a rather general ansatz, that 3-vector
fields can interact among themselves only as Yang--Mills fields minimally
coupled to gravity.Comment: Replaced with final version accepted by Classical and Quantum Gravity
(14 pages, no figures
On the emergence of random initial conditions in fluid limits
The paper presents a phenomenon occurring in population processes that start
near zero and have large carrying capacity. By the classical result of
Kurtz~(1970), such processes, normalized by the carrying capacity, converge on
finite intervals to the solutions of ordinary differential equations, also
known as the fluid limit. When the initial population is small relative to
carrying capacity, this limit is trivial. Here we show that, viewed at suitably
chosen times increasing to infinity, the process converges to the fluid limit,
governed by the same dynamics, but with a random initial condition. This random
initial condition is related to the martingale limit of an associated linear
birth and death process
The geometry of the Barbour-Bertotti theories I. The reduction process
The dynamics of interacting particles is investigated in the
non-relativistic context of the Barbour-Bertotti theories. The reduction
process on this constrained system yields a Lagrangian in the form of a
Riemannian line element. The involved metric, degenerate in the flat
configuration space, is the first fundamental form of the space of orbits of
translations and rotations (the Leibniz group). The Riemann tensor and the
scalar curvature are computed by a generalized Gauss formula in terms of the
vorticity tensors of generators of the rotations. The curvature scalar is
further given in terms of the principal moments of inertia of the system. Line
configurations are singular for . A comparison with similar methods in
molecular dynamics is traced.Comment: 15 pages, to appear in Classical and Quantum Gravit
Towards the Unification of Gravity and other Interactions: What has been Missed?
Faced with the persisting problem of the unification of gravity with other
fundamental interactions we investigate the possibility of a new paradigm,
according to which the basic space of physics is a multidimensional space
associated with matter configurations. We consider general
relativity in . In spacetime, which is a 4-dimensional subspace of
, we have not only the 4-dimensional gravity, but also other
interactions, just as in Kaluza-Klein theories. We then consider a finite
dimensional description of extended objects in terms of the center of mass,
area, and volume degrees of freedom, which altogether form a 16-dimensional
manifold whose tangent space at any point is Clifford algebra Cl(1,3). The
latter algebra is very promising for the unification, and it provides
description of fermions.Comment: 11 pages; Talk presented at "First Mediterranean Conference on
Classical and Quantum Gravity", Kolymbari, Crete, Greece, 14-18 September
200
Monte Carlo Study of Two-Color QCD with Finite Chemical Potential - Status report of Wilson fermion simulation
Using Wilson fermions, we study SU(2) lattice QCD with the chemical potential
at . The ratio of fermion determinants is evaluated at each
Metropolis link update step. We calculate the baryon number density, the
Polyakov loops and the pseudoscalar and vector masses on and lattices. Preliminary data show the pseudoscalar meson becomes massive
around , which indicates the chiral symmetry restoration. The
calculation is broken down when approaching to the transition region. We
analyze the behavior of the fermion determinant and eigen value distributions
of the determinant, which shows a peculiar ``Shell-and-Bean'' pattern near the
transition.Comment: 4 pages, 5 figures, Lattice 2000 (Finite Density
A law of large numbers approximation for Markov population processes with countably many types
When modelling metapopulation dynamics, the influence of a single patch on
the metapopulation depends on the number of individuals in the patch. Since the
population size has no natural upper limit, this leads to systems in which
there are countably infinitely many possible types of individual. Analogous
considerations apply in the transmission of parasitic diseases. In this paper,
we prove a law of large numbers for rather general systems of this kind,
together with a rather sharp bound on the rate of convergence in an
appropriately chosen weighted norm.Comment: revised version in response to referee comments, 34 page
The Definition of Mach's Principle
Two definitions of Mach's principle are proposed. Both are related to gauge
theory, are universal in scope and amount to formulations of causality that
take into account the relational nature of position, time, and size. One of
them leads directly to general relativity and may have relevance to the problem
of creating a quantum theory of gravity.Comment: To be published in Foundations of Physics as invited contribution to
Peter Mittelstaedt's 80th Birthday Festschrift. 30 page
Covariant quantization of membrane dynamics
A Lorentz covariant quantization of membrane dynamics is defined, which also
leaves unbroken the full three dimensional diffeomorphism invariance of the
membrane. Among the applications studied are the reduction to string theory,
which may be understood in terms of the phase space and constraints, and the
interpretation of physical,zero-energy states. A matrix regularization is
defined as in the light cone gauged fixed theory but there are difficulties
implementing all the gauge symmetries. The problem involves the
non-area-preserving diffeomorphisms which are realized non-linearly in the
classical theory. In the quantum theory they do not seem to have a consistent
implementation for finite N. Finally, an approach to a genuinely background
independent formulation of matrix dynamics is briefly described.Comment: Latex, 21 pages, no figure
Einstein gravity as a 3D conformally invariant theory
We give an alternative description of the physical content of general
relativity that does not require a Lorentz invariant spacetime. Instead, we
find that gravity admits a dual description in terms of a theory where local
size is irrelevant. The dual theory is invariant under foliation preserving
3-diffeomorphisms and 3D conformal transformations that preserve the 3-volume
(for the spatially compact case). Locally, this symmetry is identical to that
of Horava-Lifshitz gravity in the high energy limit but our theory is
equivalent to Einstein gravity. Specifically, we find that the solutions of
general relativity, in a gauge where the spatial hypersurfaces have constant
mean extrinsic curvature, can be mapped to solutions of a particular gauge
fixing of the dual theory. Moreover, this duality is not accidental. We provide
a general geometric picture for our procedure that allows us to trade foliation
invariance for conformal invariance. The dual theory provides a new proposal
for the theory space of quantum gravity.Comment: 27 pages. Published version (minor changes and corrections
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