1,788 research outputs found
Young Muslim women's experiences of Islam and physical education in Greece and Britain: a comparative study
Previous research suggests that Muslim women can experience particular problems when taking physical education (PE) lessons, for example with dress codes, mixed-teaching and exercise during Ramadan; and they can face restrictions in extra-curricular activities for cultural and religious reasons. The area is under-researched and there is little evidence of comparative studies that explore similarities and differences in cross-national experiences, which is the aim of this paper. Two studies conducted in Greece and Britain that explored the views of Muslim women on school experiences of physical education are compared. Both studies focused on diaspora communities, Greek Turkish girls and British Asian women, living in predominantly non-Muslim countries. Growing concerns about global divisions between 'Muslims and the West' make this a particularly pertinent study. Qualitative data were collected by interviews with 24 Greek Muslim women, and 20 British Muslim women. \ud
<P> \ud
Physical education has national curriculum status and a similar rationale in both countries but with different cultures of formality and tradition, which impacted on pupils' experiences. Data suggested that Greek and British groups held positive views towards physical education but were restricted on their participation in extra-curricular activities. For the British women religious identity and consciousness of Islamic requirements were more evident than for the Greek women. Differences in stages of acculturation, historical and socio-cultural contexts contributed to less problematic encounters with physical education for Greek Muslims who appeared more closely assimilated into the dominant culture
The Dirac equation without spinors
In the first part of the paper we give a tensor version of the Dirac
equation. In the second part we formulate and analyse a simple model equation
which for weak external fields appears to have properties similar to those of
the 2--dimensional Dirac equation.Comment: 20 pages. Submitted for publication in the proceedings of the
conference `Functional analysis, partial differential equations and
applications', Rostock (Germany) 31 August--4 September 199
The merging/AGN connection: A case for 3D spectroscopy
We discuss an ongoing study of the connection between galaxy
merging/interaction and AGN activity, based on integral field spectroscopy. We
focus on the search for AGN ionization in the central regions of mergers,
previously not classified as AGNs. We present here the science case, the
current status of the project, and plans for future observations.Comment: 4 pages, 3 figure, Euro3D Science Workshop, Cambridge, May 2003, AN,
accepte
Tight constraints on the existence of additional planets around HD 189733
We report a transit timing study of the transiting exoplanetary system HD
189733. In total we observed ten transits in 2006 and 2008 with the 2.6-m
Nordic Optical Telescope, and two transits in 2007 with the 4.2-m William
Herschel Telescope. We used Markov-Chain Monte Carlo simulations to derive the
system parameters and their uncertainties, and our results are in a good
agreement with previously published values. We performed two independent
analyses of transit timing residuals to place upper mass limits on putative
perturbing planets. The results show no evidence for the presence of planets
down to 1 Earth mass near the 1:2 and 2:1 resonance orbits, and planets down to
2.2 Earth masses near the 3:5 and 5:3 resonance orbits with HD 189733b. These
are the strongest limits to date on the presence of other planets in this
system.Comment: 10 pages, 4 figures, accepted by MNRA
Commuting symmetry operators of the Dirac equation, Killing-Yano and Schouten-Nijenhuis brackets
In this paper we derive the most general first-order symmetry operator
commuting with the Dirac operator in all dimensions and signatures. Such an
operator splits into Clifford even and Clifford odd parts which are given in
terms of odd Killing-Yano and even closed conformal Killing-Yano inhomogeneous
forms respectively. We study commutators of these symmetry operators and give
necessary and sufficient conditions under which they remain of the first-order.
In this specific setting we can introduce a Killing-Yano bracket, a bilinear
operation acting on odd Killing-Yano and even closed conformal Killing-Yano
forms, and demonstrate that it is closely related to the Schouten-Nijenhuis
bracket. An important non-trivial example of vanishing Killing-Yano brackets is
given by Dirac symmetry operators generated from the principal conformal
Killing-Yano tensor [hep-th/0612029]. We show that among these operators one
can find a complete subset of mutually commuting operators. These operators
underlie separability of the Dirac equation in Kerr-NUT-(A)dS spacetimes in all
dimensions [arXiv:0711.0078].Comment: 37 pages, no figure
A Spinor Model for Quantum Cosmology
The question of the interpretation of Wheeler-DeWitt solutions in the context
of cosmological models is addressed by implementing the Hamiltonian constraint
as a spinor wave equation in minisuperspace. We offer a relative probability
interpretation based on a non-closed vector current in this space and a
prescription for a parametrisation of classical solutions in terms of classical
time. Such a prescription can accommodate classically degenerate metrics
describing manifolds with signature change. The relative probability density,
defined in terms of a Killing vector of the Dewitt metric on minisuperspace,
should permit one to identify classical loci corresponding to geometries for a
classical manifold. This interpretation is illustrated in the context of a
quantum cosmology model for two-dimensional dilaton gravity.Comment: 17p, Lanc-Th-G940
Black Holes with Weyl Charge and Non-Riemannian Waves
A simple modification to Einstein's theory of gravity in terms of a
non-Riemannian connection is examined. A new tensor-variational approach yields
field equations that possess a covariance similar to the gauge covariance of
electromagnetism. These equations are shown to possess solutions analogous to
those found in the Einstein-Maxwell system. In particular one finds
gravi-electric and gravi-magnetic charges contributing to a spherically
symmetric static Reissner-Nordstr\"om metric. Such Weyl ``charges'' provide a
source for the non-Riemannian torsion and metric gradient fields instead of the
electromagnetic field. The theory suggests that matter may be endowed with
gravitational charges that couple to gravity in a manner analogous to
electromagnetic couplings in an electromagnetic field. The nature of
gravitational coupling to spinor matter in this theory is also investigated and
a solution exhibiting a plane-symmetric gravitational metric wave coupled via
non-Riemannian waves to a propagating spinor field is presented.Comment: 18 pages Plain Tex (No Figures), Classical and Quantum Gravit
An Einstein-Hilbert Action for Axi-Dilaton Gravity in 4-Dimensions
We examine the axi-dilatonic sector of low energy string theory and
demonstrate how the gravitational interactions involving the axion and dilaton
fields may be derived from a geometrical action principle involving the
curvature scalar associated with a non-Riemannian connection. In this geometry
the antisymmetric tensor 3-form field determines the torsion of the connection
on the frame bundle while the gradient of the metric is determined by the
dilaton field. By expressing the theory in terms of the Levi-Civita connection
associated with the metric in the ``Einstein frame'' we confirm that the field
equations derived from the non-Riemannian Einstein-Hilbert action coincide with
the axi-dilaton sector of the low energy effective action derived from string
theory.Comment: 6 pages Plain Tex (No Figures), Letter to Editor Classical and
Quantum Gravit
Microjansky radio sources in DC0107-46 (Abell 2877)
The cluster DC0107-46 (Abell 2877) lies within the Phoenix Deep Survey, made
at 1.4 GHz with the Australia Telescope Compact Array. Of 89 known optical
cluster members, 70 lie within the radio survey area. Of these 70 galaxies, 15
(21%) are detected, with luminosities as faint as 10^20 W/Hz. Spectroscopic
observations are available for 14/15 of the radio-detected cluster galaxies.
Six galaxies show only absorption features and are typical low-luminosity AGN
radio sources. One galaxy hosts a Seyfert 2 nucleus, two are star-forming
galaxies, and the remaining five may be star-forming galaxies, AGNs, or both.Comment: 14 pages, 3 figures, Accepted by ApJS (v128n2p JUN 2000 issue
- …