2,958 research outputs found
Transnationalism and Social Work Education
Transnational movements, networks, and relationships are everywhere in this “world on the move” (Williams & Graham, 2014, p. i1). Transnational peoples maintain relationships of interdependence and support with families and communities in their places of origin, often returning regularly, while starting new lives and making new connections. Transnationalism is characterized by mobilities and networks, by social integration, and by extended and extensive relationship ties of family, neighborhood, religious faith, or combinations thereof (Valtonen, 2008). While disciplines across the world including sociology, human geography, and cultural anthropology engage with the implications of transnationalism (Bauböck & Faist, 2010), social work in England and mainland Europe has not achieved similar levels of engagement. As Cox and Geisen state: “the social world is being transformed by migration and social work is playing catch-up” (2014, p. i162)
Time and Time Functions in Parametrized Non-Relativistic Quantum Mechanics
The ``evolving constants'' method of defining the quantum dynamics of
time-reparametrization-invariant theories is investigated for a particular
implementation of parametrized non-relativistic quantum mechanics (PNRQM). The
wide range of time functions that are available to define evolving constants
raises issues of interpretation, consistency, and the degree to which the
resulting quantum theory coincides with, or generalizes, the usual
non-relativistic theory. The allowed time functions must be restricted for the
predictions of PNRQM to coincide with those of usual quantum theory. They must
be restricted to have a notion of quantum evolution in a time-parameter
connected to spacetime geometry. They must be restricted to prevent the theory
from making inconsistent predictions for the probabilities of histories.
Suitable restrictions can be introduced in PNRQM but these seem unlikely to
apply to a reparametrization invariant theory like general relativity.Comment: 18pages, 1postscript figure in separate file, uses REVTEX 3.
Another weak first order deconfinement transition: three-dimensional SU(5) gauge theory
We examine the finite-temperature deconfinement phase transition of
(2+1)-dimensional SU(5) Yang-Mills theory via non-perturbative lattice
simulations. Unsurprisingly, we find that the transition is of first order,
however it appears to be weak. This fits naturally into the general picture of
"large" gauge groups having a first order deconfinement transition, even when
the center symmetry associated with the transition might suggest otherwise.Comment: 17 pages, 8 figure
Universal bifurcation property of two- or higher-dimensional dissipative systems in parameter space: Why does 1D symbolic dynamics work so well?
The universal bifurcation property of the H\'enon map in parameter space is
studied with symbolic dynamics. The universal- region is defined to
characterize the bifurcation universality. It is found that the universal-
region for relative small is not restricted to very small values. These
results show that it is also a universal phenomenon that universal sequences
with short period can be found in many nonlinear dissipative systems.Comment: 10 pages, figures can be obtained from the author, will appeared in
J. Phys.
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The Risk of Unexploded Ordnance on Construction Sites in London
Greater London, among many large cities, was subject to bombing by the German military in both the World Wars and was the target of many air raids during the Second World War (WW2). This was particularly the case during the Blitz, September 1940 – May 1941, when over 28,000 high explosive bombs and parachute mines were dropped on London. Post war research conducted in 1949 estimated that approximately 12,750 t of bombs, including V1 and V2 rockets, were dropped on London. The night of 16th – 17th April 1941 was one of the worst bombing raids, when 446 t of bombs were dropped on London and over 58 t did not detonate. Unexploded bombs remain buried underground today, as they were unidentified at the time or abandoned owing to difficulties in recovering them. Uncharted bombs continue to pose a potentially significant hazard for developments around London. This paper considers the probability of discovering unexploded ordnance (UXO), particularly WW2 ordnance, during intrusive groundworks in London. The prevalence of unexploded ordnance has been assessed using data obtained from governmental organisations to estimate the likelihood of discovery in London
Quantum Zeno Effect and Light-Dark Periods for a Single Atom
The quantum Zeno effect (QZE) predicts a slow-down of the time development of
a system under rapidly repeated ideal measurements, and experimentally this was
tested for an ensemble of atoms using short laser pulses for non-selective
state measurements. Here we consider such pulses for selective measurements on
a single system. Each probe pulse will cause a burst of fluorescence or no
fluorescence. If the probe pulses were strictly ideal measurements, the QZE
would predict periods of fluorescence bursts alternating with periods of no
fluorescence (light and dark periods) which would become longer and longer with
increasing frequency of the measurements. The non-ideal character of the
measurements is taken into account by incorporating the laser pulses in the
interaction, and this is used to determine the corrections to the ideal case.
In the limit, when the time between the laser pulses goes to zero, no freezing
occurs but instead we show convergence to the familiar macroscopic light and
dark periods of the continuously driven Dehmelt system. An experiment of this
type should be feasible for a single atom or ion in a trapComment: 16 pages, LaTeX, a4.sty; to appear in J. Phys.
Moduli stabilization with positive vacuum energy
We study the effect of anomalous U(1) gauge groups in string theory
compactification with fluxes. We find that, in a gauge invariant formulation,
consistent AdS vacua appear breaking spontaneously supergravity. Non vanishing
D-terms from the anomalous symmetry act as an uplifting potential and could
allow for de Sitter vacua. However, we show that in this case the gravitino is
generically (but not always) much heavier than the electroweak scale. We show
that alternative uplifting scheme based on corrections to the Kahler potential
can be compatible with a gravitino mass in the TeV range.Comment: 20 pages, 1 figur
The domestic and gendered context for retirement
Against a global backdrop of population and workforce ageing, successive UK governments have encouraged people to work longer and delay retirement. Debates focus mainly on factors affecting individuals’ decisions on when and how to retire. We argue that a fuller understanding of retirement can be achieved by recognizing the ways in which individuals’ expectations and behaviours reflect a complicated, dynamic set of interactions between domestic environments and gender roles, often established over a long time period, and more temporally proximate factors. Using a qualitative data set, we explore how the timing, nature and meaning of retirement and retirement planning are played out in specific domestic contexts. We conclude that future research and policies surrounding retirement need to: focus on the household, not the individual; consider retirement as an often messy and disrupted process and not a discrete event; and understand that retirement may mean very different things for women and for men
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