5,119 research outputs found
Community Land Trusts, affordable housing and community organising in low-income neighbourhoods
Community Land Trusts (CLTs) offer a community-led response to housing problems and can provide affordable housing for low-income residents. Generally the academic work on CLTs remains underdeveloped, particularly in the UK, although some argue that they can be an efficient way in which to manage scarce resources while others have noted that CLTs can provide a focal point for community resistance. In this article we provide evidence on two active CLTs in inner urban areas in major US cities, New York and Boston. In Cooper Square, Lower East Side Manhattan and Dudley Street, south Boston, we see the adoption of different approaches to development suggesting that we should speak of models of CLTs rather than assuming a single operational approach. The cases we present indicate both radical and reformist responses to the state and market provision of housing and neighbourhood sustainability. They also suggest community activism can prove to be significant in securing land and the development of the CLT
Neighbourhood Renewal Fund Phase Two Create Project Evaluation.
The Social Research & Regeneration Unit at the University of Plymouth was commissioned by Plymouth 2020 Partnership to evaluate the Community Renewal Education And Training Enterprise (CREATE) project as part of Plymouth’s overall Neighbourhood Renewal Fund (NRF) Phase Two Evaluation. The CREATE evaluation was conducted between the autumn of 2005 and January 2006. This report summarises the main research findings
Spin glasses without time-reversal symmetry and the absence of a genuine structural glass transition
We study the three-spin model and the Ising spin glass in a field using
Migdal-Kadanoff approximation. The flows of the couplings and fields indicate
no phase transition, but they show even for the three-spin model a slow
crossover to the asymptotic high-temperature behaviour for strong values of the
couplings. We also evaluated a quantity that is a measure of the degree of
non-self-averaging, and we found that it can become large for certain ranges of
the parameters and the system sizes. For the spin glass in a field the maximum
of non-self-averaging follows for given system size a line that resembles the
de Almeida-Thouless line. We conclude that non-self-averaging found in
Monte-Carlo simulations cannot be taken as evidence for the existence of a
low-temperature phase with replica-symmetry breaking. Models similar to the
three-spin model have been extensively discussed in order to provide a
description of structural glasses. Their theory at mean-field level resembles
the mode-coupling theory of real glasses. At that level the one-step replica
symmetry approach breaking predicts two transitions, the first transition being
dynamical and the second thermodynamical. Our results suggest that in real
finite dimensional glasses there will be no genuine transitions at all, but
that some features of mean-field theory could still provide some useful
insights.Comment: 11 pages, 11 figure
Evidence for the droplet/scaling picture of spin glasses
We have studied the Parisi overlap distribution for the three dimensional
Ising spin glass in the Migdal-Kadanoff approximation. For temperatures T
around 0.7Tc and system sizes upto L=32, we found a P(q) as expected for the
full Parisi replica symmetry breaking, just as was also observed in recent
Monte Carlo simulations on a cubic lattice. However, for lower temperatures our
data agree with predictions from the droplet or scaling picture. The failure to
see droplet model behaviour in Monte Carlo simulations is due to the fact that
all existing simulations have been done at temperatures too close to the
transition temperature so that sytem sizes larger than the correlation length
have not been achieved.Comment: 4 pages, 6 figure
Absence of aging in the remanent magnetization in Migdal-Kadanoff spin glasses
We study the non-equilibrium behavior of three-dimensional spin glasses in
the Migdal-Kadanoff approximation, that is on a hierarchical lattice. In this
approximation the model has an unique ground state and equilibrium properties
correctly described by the droplet model. Extensive numerical simulations show
that this model lacks aging in the remanent magnetization as well as a maximum
in the magnetic viscosity in disagreement with experiments as well as with
numerical studies of the Edwards-Anderson model. This result strongly limits
the validity of the droplet model (at least in its simplest form) as a good
model for real spin glasses.Comment: 4 pages and 3 figures. References update
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