5,389 research outputs found
Society seen through the prism of space: outline of a theory of society and space
Two questions challenge the student of space and society above all others: will new technologies
change the spatial basis of society ? And if so, will this have an impact on society itself ?
For the urbanist, these two questions crystallise into one: what will the future of cities have
to do with their past ? Too often these questions are dealt with as though they were only
matters of technology. But they are much more than that. They are deep and difficult questions
about the interdependence of technology, space and society that we do not yet have the
theoretical apparatus to answer. We know that previous �revolutions� in technology such as
agriculture, urbanism and industrialisation associated radical changes in space with no less
radical changes in social institutions. But we do not know how far these linkages were
contingent or necessary. We do not, in short, have a theory of society and space adequate to
account for where we are now, and therefore we have no reasonable theoretical base for
speculating about the future. In this paper, I suggest that a major reason for this theoretical
deficit is that most previous attempts to build a theory of society and space have looked at
society and tried to find space in its output. The result has been that the constructive role of
space in creating and and sustaining society has not been brought to the fore, or if it has, only
in a way which is too general to permit the detailed specification of mechanisms. In this
paper I try to reverse the normal order of things this by looking first at space and trying the
discern society through space: by looking at society through the prism of space. Through this
I try to define key mechanisms linking space to society and then use these to suggest how the
questions about the future of cities and societies might be better defined
SR and Neutron Diffraction Investigations on Reentrant Ferromagnetic Superconductor Eu(Fe{0.86}Ir{0.14})2As2
Results of muon spin relaxation (SR) and neutron powder diffraction
measurements on a reentrant superconductor Eu(FeIr)As
are presented. Eu(FeIr)As exhibits superconductivity
at ~K competing with long range ordered Eu
moments below K. A reentrant behavior (manifested by nonzero
resistivity in the temperature range 10--17.5 K) results from an exquisite
competition between the superconductivity and magnetic order. The zero field
SR data confirm the long range magnetic ordering below K. The transition temperature is found to increase with increasing
magnetic field in longitudinal field SR which along with the neutron
diffraction results, suggests the transition to be ferromagnetic. The neutron
diffraction data reveal a clear presence of magnetic Bragg peaks below which could be indexed with propagation vector k = (0, 0, 0), confirming a
long range magnetic ordering in agreement with SR data. Our analysis of
the magnetic structure reveals an ordered magnetic moment of (at 1.8 K) on the Eu atoms and they form a ferromagnetic structure with
moments aligned along the -axis. No change in the magnetic structure is
observed in the reentrant or superconducting phases and the magnetic structure
remains same for 1.8 K . No clear evidence of
structural transition or Fe moment ordering was found.Comment: 9 pages, 7 figures, to appear in Phys. Rev.
Obscured clusters.IV. The most massive stars in [DBS2003]179
Aims. We report new results for the massive evolved and main sequence members
of the young galactic cluster DBS2003 179. We determine the physical parameters
and investigate the high-mass stellar content of the cluster, as well as of its
close vicinity. Methods. Our analysis is based on ISAAC/VLT moderate-resolution
(R\approx4000) infrared spectroscopy of the brightest cluster members. We
derive stellar parameters for sixteen of the stellar members, using full
non-LTE modeling of the obtained spectra. Results. The cluster contains three
late WN or WR/LBV stars (Obj 4, Obj 15, and Obj 20:MDM32) and at least 5 OIf
and 5 OV stars. According to the Hertzsprung-Russell diagram for DBS2003 179,
the WR stars show masses above 85Msun, the OIf stars are between 40 and 80Msun,
and the main sequence O stars are >20Msun. There are indications of binarity
for Obj 4 and Obj 11, and Obj 3 shows a variable spectrum. The cluster is
surrounded by a continuous protostar formation region most probably triggered
by DBS2003 179. Conclusions. We confirm that DBS2003 179 is young massive
cluster (2.5 10^4Msun) very close to the Galactic center at the distance of
7.9+-0.8 kpc.Comment: 14 pages, 16 figures, accepted in A&
Home sweet home: a critical comment on Saunders and Williams
While accepting the need for research which focuses on the social meaning of the home, this article takes issue with some of Saunders’ and Williams’ formulations for a research programme — in particular, the emphasis given to physical and design features of the home at the expense of an understanding of more fundamental gender and generational relations within the home. It attempts to uncover the assumptions lying behind those formulations, to clarify some of the conceptual confusions, and to point out some of the serious theoretical difficulties which such formulations have to resolve. It argues that theoretical advance in this area does not have to depend upon the adoption of a Weberian perspective, but must be situated within a broader theory of the production and maintenance of ideology, and this theory must be explicitly linked with theories of power and kinship. In particular, it is emphasised that power relations within the home, associated mainly with gender and age differences, need to be investigated in greater depth if the social significance of the home is to be properly understood
Physical properties of noncentrosymmetric superconductor LaIrSi3: A {\mu}SR study
The results of heat capacity C_p(T, H) and electrical resistivity \rho(T,H)
measurements down to 0.35 K as well as muon spin relaxation and rotation
(\muSR) measurements on a noncentrosymmetric superconductor LaIrSi3 are
presented. Powder neutron diffraction confirmed the reported noncentrosymmetric
body-centered tetragonal BaNiSn3-type structure (space group I4\,mm) of
LaIrSi3. The bulk superconductivity is observed below T_c = 0.72(1) K. The
intrinsic \Delta C_e/\gamma_n T_c = 1.09(3) is significantly smaller than the
BCS value of 1.43, and this reduction is accounted by the \alpha-model of BCS
superconductivity. The analysis of the superconducting state C_e(T) data by the
single-band \alpha-model indicates a moderately anisotropic order parameter
with the s-wave gap \Delta(0)/k_B T_c = 1.54(2) which is lower than the BCS
value of 1.764. Our estimates of various normal and superconducting state
parameters indicate a weakly coupled electron-phonon driven type-I s-wave
superconductivity in LaIrSi3. The \muSR results also confirm the conventional
type-I superconductivity in LaIrSi3 with a preserved time reversal symmetry and
hence a singlet pairing superconducting ground state.Comment: 11 pages, 8 figures, 2 table
Evidence for a dynamical ground state in the frustrated pyrohafnate Tb2Hf2O7
We report the physical properties of Tb2Hf2O7 based on ac magnetic
susceptibility \chi_ac(T), dc magnetic susceptibility \chi(T), isothermal
magnetization M(H), and heat capacity C_p(T) measurements combined with muon
spin relaxation (\muSR) and neutron powder diffraction measurements. No
evidence for long-range magnetic order is found down to 0.1 K. However,
\chi_ac(T) data present a frequency-dependent broad peak (near 0.9 K at 16 Hz)
indicating slow spin dynamics. The slow spin dynamics is further evidenced from
the \muSR data (characterized by a stretched exponential behavior) which show
persistent spin fluctuations down to 0.3 K. The neutron powder diffraction data
collected at 0.1 K show a broad peak of magnetic origin (diffuse scattering)
but no magnetic Bragg peaks. The analysis of the diffuse scattering data
reveals a dominant antiferromagnetic interaction in agreement with the negative
Weiss temperature. The absence of long-range magnetic order and the presence of
slow spin dynamics and persistent spin fluctuations together reflect a
dynamical ground state in Tb2Hf2O7.Comment: 11 pages and 8 figure
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