27,442 research outputs found

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### Diasporic Film in Communities

The Diasporic Film in Communities project set out to critically examine the role of Diasporic film culture in Diasporic communities. A case study approach was used to explore how three postcolonial publics (African-Caribbean, Chinese and South Asian) mobilise around film, interface with cultural organisations and reflect on their significance as film communities.AHRC- Research Grant, Project Reference: AH/J011991/

### â€˜Keeping it realâ€™: the politics of Channel 4's multiculturalism, mainstreaming and mandates

This article is a post-print version of the published article which may be viewed at the link below. Â© The Author 2008. Published by Oxford University Press on behalf of Screen. All rights reserved.When Channel 4 decided how it was going to fill what was described in the Annan Report as â€˜the empty room of British broadcastingâ€™, it was agreed that Britain's Africans, Caribbeans and Asians were to be important residents. This was meaningful for Channel 4 because it was tasked with providing what Stephen Lambert then described as â€˜opportunities for talents which had previously not been fully servedâ€™ and with serving needs â€˜which have not been fully definedâ€™.
And yet the recent history of the channel has been characterized by the closing stages of a particular kind of â€˜public serviceâ€™ approach; one in which ethnic minorities have become simultaneously integrated in and disconnected from mainstream output in distinct ways. Twenty-five years on, the channel is caught up in the difficulties facing the structuring of public service broadcasting and in the challenges posed by the highly contentious politics of recognition for the settlement of the relation between a variety of social rights. On the one hand, black and Asian Britons, who as part of the postcolonial phase of migration to the UK might be regarded as the â€˜old ethnicsâ€™, do not now appear to be a priority for Channel 4. On the other, the legacy of the relationship between Channel 4, these communities and broader ideals of â€˜multiculturalismâ€™ appears to be strong, not least according to the channel's current claims

### Gauge Transformations, BRST Cohomology and Wigner's Little Group

We discuss the (dual-)gauge transformations and BRST cohomology for the two
(1 + 1)-dimensional (2D) free Abelian one-form and four (3 + 1)-dimensional
(4D) free Abelian 2-form gauge theories by exploiting the (co-)BRST symmetries
(and their corresponding generators) for the Lagrangian densities of these
theories. For the 4D free 2-form gauge theory, we show that the changes on the
antisymmetric polarization tensor e^{\mu\nu} (k) due to (i) the (dual-)gauge
transformations corresponding to the internal symmetry group, and (ii) the
translation subgroup T(2) of the Wigner's little group, are connected with
each-other for the specific relationships among the parameters of these
transformation groups. In the language of BRST cohomology defined w.r.t. the
conserved and nilpotent (co-)BRST charges, the (dual-)gauge transformed states
turn out to be the sum of the original state and the (co-)BRST exact states. We
comment on (i) the quasi-topological nature of the 4D free 2-form gauge theory
from the degrees of freedom count on e^{\mu\nu} (k), and (ii) the Wigner's
little group and the BRST cohomology for the 2D one-form gauge theory {\it
vis-{\`a}-vis} our analysis for the 4D 2-form gauge theory.Comment: LaTeX file, 29 pages, misprints in (3.7), (3.8), (3.9), (3.13) and
(4.14)corrected and communicated to IJMPA as ``Erratum'

### BRST cohomology and Hodge decomposition theorem in Abelian gauge theory

We discuss the Becchi-Rouet-Stora-Tyutin (BRST) cohomology and Hodge
decomposition theorem for the two dimensional free U(1) gauge theory. In
addition to the usual BRST charge, we derive a local, conserved and nilpotent
co(dual)-BRST charge under which the gauge-fixing term remains invariant. We
express the Hodge decomposition theorem in terms of these charges and the
Laplacian operator. We take a single photon state in the quantum Hilbert space
and demonstrate the notion of gauge invariance, no-(anti)ghost theorem,
transversality of photon and establish the topological nature of this theory by
exploiting the concepts of BRST cohomology and Hodge decomposition theorem. In
fact, the topological nature of this theory is encoded in the vanishing of the
Laplacian operator when equations of motion are exploited. On the two
dimensional compact manifold, we derive two sets of topological invariants with
respect to the conserved and nilpotent BRST- and co-BRST charges and express
the Lagrangian density of the theory as the sum of terms that are BRST- and
co-BRST invariants. Mathematically, this theory captures together some of the
key features of both Witten- and Schwarz type of topological field theories.Comment: 20 pages, LaTeX, no figures, Title and text have been changed,
Journal reference is given, some references have been adde

### Superfield approach to symmetry invariance in QED with complex scalar fields

We show that the Grassmannian independence of the super Lagrangian density,
expressed in terms of the superfields defined on a (4, 2)-dimensional
supermanifold, is a clear-cut proof for the Becchi-Rouet-Stora-Tyutin (BRST)
and anti-BRST invariance of the corresoponding four (3 + 1)-dimensional (4D)
Lagrangian density that describes the interaction between the U(1) gauge field
and the charged complex scalar fields. The above 4D field theoretical model is
considered on a (4, 2)-dimensional supermanifold parametrized by the ordinary
four spacetime variables x^\mu (with \mu = 0, 1, 2, 3) and a pair of
Grassmannian variables \theta and \bar\theta (with \theta^2 = \bar\theta^2 = 0,
\theta \bar\theta + \bar\theta \theta = 0). Geometrically, the (anti-)BRST
invariance is encoded in the translation of the super Lagrangian density along
the Grassmannian directions of the above supermanifold such that the outcome of
this shift operation is zero.Comment: LaTeX file, 14 pages, minor changes in the title and text, version to
appear in ``Pramana - Journal of Physics'

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### Public understanding of regimes of risk regulation: Focus groups with citizens and consumers

This report investigates the nature of public understanding of risk and regulation. Issues of risk and regulation are both significant for the public and recognised as such by them. It shows that the public has strong and diverse views on the regulation of the risks they face in their daily lives, and is often critical of the ways in which risks are managed. This raises key issues for regulators and other stakeholders concerned with risk management, public awareness and consumer rights and responsibilities.
As part of the ESRC-funded research project, Public Understanding of Regimes of Risk Regulation, part of the SCARR network, the authors conducted sixteen focus groups with a cross-section of the UK public. The discussions ranged across risk and regulation issues broadly, though two sectors - communications and financial services â€“ were explored in detail

### Wigner's little group and BRST cohomology for one-form Abelian gauge theory

We discuss the (dual-)gauge transformations for the gauge-fixed Lagrangian
density and establish their intimate connection with the translation subgroup
T(2) of the Wigner's little group for the free one-form Abelian gauge theory in
four $(3 + 1)$-dimensions (4D) of spacetime. Though the relationship between
the usual gauge transformation for the Abelian massless gauge field and T(2)
subgroup of the little group is quite well-known, such a connection between the
dual-gauge transformation and the little group is a new observation. The above
connections are further elaborated and demonstrated in the framework of
Becchi-Rouet-Stora-Tyutin (BRST) cohomology defined in the quantum Hilbert
space of states where the Hodge decomposition theorem (HDT) plays a very
decisive role.Comment: LaTeX file, 17 pages, Journal-ref. give

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