4,798 research outputs found
Trade union strategy in Sydney's construction union: a Roman Catholic perspective
Rudd Government ministers have talked tough towards the more militant Australian trade unions since coming to office in November 2007. However, despite this, it is still fair to say that the removal of the Howard-Costello Government reduced neo-liberal hegemony by altering the invisible balance of power between capital and labour in the construction industry. Using a set of case studies, based on data obtained from fieldwork at the New South Wales, Australia branch of the Construction Forestry Mining and Energy Union (CFMEU), we document key elements of union strategy at the branch level in the year immediately after the removal of the Howard-Costello Government. A key aspect of branch level strategy was building site visits by a team of organisers, led by the divisional state secretary, designed to rebuild influence on site and reconnect with workers. Furthermore, the CFMEUâs hiring of foreign language speaking organisers and production of foreign language publications is a praiseworthy attempt to reach out to ethnic minority workers and bring them under the âmainstreamâ union umbrella. We use a theory framework of Roman Catholic social teaching to frame our discussions
Multiparticle Interference, GHZ Entanglement, and Full Counting Statistics
We investigate the quantum transport in a generalized N-particle Hanbury
Brown--Twiss setup enclosing magnetic flux, and demonstrate that the Nth-order
cumulant of current cross correlations exhibits Aharonov-Bohm oscillations,
while there is no such oscillation in all the lower-order cumulants. The
multiparticle interference results from the orbital Greenberger-Horne-Zeilinger
entanglement of N indistinguishable particles. For sufficiently strong
Aharonov-Bohm oscillations the generalized Bell inequalities may be violated,
proving the N-particle quantum nonlocality.Comment: 4 pages, 1 figure, published versio
Quantifying mixed-state quantum entanglement by optimal entanglement witness
We develop an approach of quantifying entanglement in mixed quantum states by
the optimal entanglement witness operator. We identify the convex set of mixed
states for which a single witness provides the exact value of an entanglement
measure, and show that the convexity, properties, and symmetries of
entanglement or of a target state considerably fix the form of the optimal
witness. This greatly reduces difficulty in computing and experimentally
determining entanglement measures. As an example, we show how to experimentally
quantify bound entanglement in four-qubit noisy Smolin states and three-qubit
Greenberger-Horne-Zeilinger (GHZ) entanglement under white noise. For general
measures and states, we provide a numerical method to efficiently optimize
witness.Comment: Supplemental material is include
X-ray reverberation in 1H0707-495 revisited
The narrow-line Seyfert 1 galaxy 1H0707-495 has previously been identified as
showing time lags between flux variations in the soft- (0.3-1 keV) and
medium-energy (1-4 keV) X-ray bands that oscillate between positive and
negative values as a function of the frequency of the mode of variation. Here
we measure and analyse the lags also between a harder X-ray band (4-7.5 keV)
and the soft and medium bands, using existing XMM-Newton data, and demonstrate
that the entire spectrum of lags, considering both the full energy range,
0.3-7.5 keV, and the full frequency range, 10^-5 < nu < 10^-2 Hz, are
inconsistent with previous claims of arising as reverberation associated with
the inner accretion disk. Instead we demonstrate that a simple reverberation
model, in which scattering or reflection is present in all X-ray bands,
explains the full set of lags without requiring any ad hoc explanation for the
time lag sign changes. The range of time delays required to explain the
observed lags extends up to about 1800 s in the hard band. The results are
consistent with reverberation caused by scattering of X-rays passing through an
absorbing medium whose opacity decreases with increasing energy and that
partially-covers the source. A high covering factor of absorbing and scattering
circumnuclear material is inferred.Comment: Accepted for publication in MNRA
Minimax optimization of entanglement witness operator for the quantification of three-qubit mixed-state entanglement
We develop a numerical approach for quantifying entanglement in mixed quantum
states by convex-roof entanglement measures, based on the optimal entanglement
witness operator and the minimax optimization method. Our approach is
applicable to general entanglement measures and states and is an efficient
alternative to the conventional approach based on the optimal pure-state
decomposition. Compared with the conventional one, it has two important merits:
(i) that the global optimality of the solution is quantitatively verifiable,
and (ii) that the optimization is considerably simplified by exploiting the
common symmetry of the target state and measure. To demonstrate the merits, we
quantify Greenberger-Horne-Zeilinger (GHZ) entanglement in a class of
three-qubit full-rank mixed states composed of the GHZ state, the W state, and
the white noise, the simplest mixtures of states with different genuine
multipartite entanglement, which have not been quantified before this work. We
discuss some general properties of the form of the optimal witness operator and
of the convex structure of mixed states, which are related to the symmetry and
the rank of states
Effect of operating parameters and cleaning on the performance of ceramic membranes treating partially clarified sugar cane juice
The performance of ceramic membranes with pore sizes of 0.05 and 0.10 mm in purifying limed and partially clarified sugar cane juice was investigated under different operating conditions. From various operating conditions and strategies, switching off the permeate for 5 seconds for every 5 minutes (S5sT5 m) by an automated control valve provided higher flux. From the three pH experiments conducted on the 0.05 mm membrane, the best performance was observed at a pH of 7.5. Amongst the four fouling models tested, the cake filtration model fitted the performance of both membranes with higher accuracy at a transmembrane pressure of 0.5 bar. Filtering the cane juice through the membrane reduced the turbidity by 99.7%, color by 15%, and the starch concentration by 80% as well as increased the purity by 1.4%. The effective cleaning chemical composition from experimental results showed that 1% NaOH and 3000 ppm NaOCl solution performed the best but only for the experiments that were treating limed and partially clarified juice at pH 7.5.<br /
A Droplet State in an Interacting Two-Dimensional Electron System
It is well known that the dielectric constant of two-dimensional (2D)
electron system goes negative at low electron densities. A consequence of the
negative dielectric constant could be the formation of the droplet state. The
droplet state is a two-phase coexistence region of high density liquid and low
density "gas". In this paper, we carry out energetic calculations to study the
stability of the droplet ground state. The possible relevance of the droplet
state to recently observed 2D metal-insulator transition is also discussed.Comment: 4 pages, 4 figures. To appear in Phys. Rev. B (Rapid Communications
Supersymmetry approach to nuclear-spin-polarization-induced quantum dot structure calculations
In nuclear-spin-polarization-induced quantum dots the electrons are confined
through local nuclear spin polarization. The model electron confinement
potential is time-dependent due to the nuclear spin diffusion and relaxation
processes. It can be well-approximated by a Gaussian curve which is not an
exactly solvable potential. We demonstrate that it can also be approximated by
multisoliton potentials for the zero value of the angular momentum and by their
singular analogues for other values of momentum without any loss of
calculational accuracy. We obtain these potentials by supersymmetric (or
equivalently Darboux) transformations from the zero potential. The main
advantage of such potentials is that they are exactly solvable. Time-dependence
of the nuclear-spin-polarization-induced quantum dot energy levels is found.Comment: Physica E (in press) (2005
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