79,157 research outputs found
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Doing Good and Looking Good in Global Humanitarian Reporting: Is Philanthrojournalism good news?
This chapter investigates if and how a private donor’s apparent motivation to ‘look good’ – or to generate symbolic capital – interacts with a news organization’s ability to ‘do good’ by producing public service content. We address this issue by reporting on the findings of a year-long study of the online humanitarian news organisation – IRIN – as it became primarily funded by a new donor. We argue that whilst it is possible that the Foundation’s pursuit of symbolic capital may have had some effect on how IRIN sought to ‘do good’, it did not appear to affect the extent to which IRIN was either willing or able to ‘do good’. Indeed, our analysis makes clear that the influence of the Foundation only had an effect on IRIN when it combined with other factors, especially journalists’ own values and organizational strategies. Ultimately, this case highlights the limits of generalized claims about the likely influence of a donor’s desire to ‘look good’ on a news organization
When a quantum measurement can be implemented locally ... and when it cannot
Local operations on subsystems and classical communication between parties
(LOCC) constitute the most general protocols available on spatially separated
quantum systems. Every LOCC protocol implements a separable generalized
measurement -- a complete measurement for which every outcome corresponds to a
tensor product of operators on individual subsystems -- but it is known that
there exist separable measurements that cannot be implemented by LOCC. A
longstanding problem in quantum information theory is to understand the
difference between LOCC and the full set of separable measurements. In this
paper, we show how to construct an LOCC protocol to implement an arbitrary
separable measurement, except that with those measurements for which no LOCC
protocol exists, the method shows explicitly that this is the case.Comment: 21 pages, 7 figures. Extensively revised to include details of all
arguments, explicitly proving all results in full rigor. Version 3 has
sections reordered and other restructuring, but otherwise contains the same
discussion as version
Recommended from our members
Foundation support for international non-profit news: Mapping the funding landscape
Physics of thin-film ferroelectric oxides
This review covers the important advances in recent years in the physics of
thin film ferroelectric oxides, the strongest emphasis being on those aspects
particular to ferroelectrics in thin film form. We introduce the current state
of development in the application of ferroelectric thin films for electronic
devices and discuss the physics relevant for the performance and failure of
these devices. Following this we cover the enormous progress that has been made
in the first principles computational approach to understanding ferroelectrics.
We then discuss in detail the important role that strain plays in determining
the properties of epitaxial thin ferroelectric films. Finally, we look at the
emerging possibilities for nanoscale ferroelectrics, with particular emphasis
on ferroelectrics in non conventional nanoscale geometries.Comment: This is an invited review for Reviews of Modern Physics. We welcome
feedback and will endeavour to incorporate comments received promptly into
the final versio
General properties of cosmological models with an Isotropic Singularity
Much of the published work regarding the Isotropic Singularity is performed
under the assumption that the matter source for the cosmological model is a
barotropic perfect fluid, or even a perfect fluid with a -law equation
of state. There are, however, some general properties of cosmological models
which admit an Isotropic Singularity, irrespective of the matter source. In
particular, we show that the Isotropic Singularity is a point-like singularity
and that vacuum space-times cannot admit an Isotropic Singularity. The
relationships between the Isotropic Singularity, and the energy conditions, and
the Hubble parameter is explored. A review of work by the authors, regarding
the Isotropic Singularity, is presented.Comment: 18 pages, 1 figur
Virtual acoustics displays
The real time acoustic display capabilities are described which were developed for the Virtual Environment Workstation (VIEW) Project at NASA-Ames. The acoustic display is capable of generating localized acoustic cues in real time over headphones. An auditory symbology, a related collection of representational auditory 'objects' or 'icons', can be designed using ACE (Auditory Cue Editor), which links both discrete and continuously varying acoustic parameters with information or events in the display. During a given display scenario, the symbology can be dynamically coordinated in real time with 3-D visual objects, speech, and gestural displays. The types of displays feasible with the system range from simple warnings and alarms to the acoustic representation of multidimensional data or events
Phase boundaries in deterministic dense coding
We consider dense coding with partially entangled states on bipartite systems
of dimension , studying the conditions under which a given number of
messages, , can be deterministically transmitted. It is known that the
largest Schmidt coefficient, , must obey the bound , and considerable empirical evidence points to the conclusion that there
exist states satisfying for every and except the
special cases and . We provide additional conditions under
which this bound cannot be reached -- that is, when it must be that
-- yielding insight into the shapes of boundaries separating
entangled states that allow messages from those that allow only . We
also show that these conclusions hold no matter what operations are used for
the encoding, and in so doing, identify circumstances under which unitary
encoding is strictly better than non-unitary.Comment: 7 pages, 1 figur
Impact of layer defects in ferroelectric thin films
Based on a modified Ising model in a transverse field we demonstrate that
defect layers in ferroelectric thin films, such as layers with impurities,
vacancies or dislocations, are able to induce a strong increase or decrease of
the polarization depending on the variation of the exchange interaction within
the defect layers. A Green's function technique enables us to calculate the
polarization, the excitation energy and the critical temperature of the
material with structural defects. Numerically we find the polarization as
function of temperature, film thickness and the interaction strengths between
the layers. The theoretical results are in reasonable accordance to
experimental datas of different ferroelectric thin films.Comment: 17 pages, 8 figure
What do gas-rich galaxies actually tell us about modified Newtonian dynamics?
It has recently been claimed that measurements of the baryonic Tully-Fisher
relation (BTFR), a power-law relationship between the observed baryonic masses
and outer rotation velocities of galaxies, support the predictions of modified
Newtonian dynamics for the slope and scatter in the relation, while challenging
the cold dark matter (CDM) paradigm. We investigate these claims, and find
that: 1) the scatter in the data used to determine the BTFR is in conflict with
observational uncertainties on the data; 2) these data do not make strong
distinctions regarding the best-fit BTFR parameters; 3) the literature contains
a wide variety of measurements of the BTFR, many of which are discrepant with
the recent results; and 4) the claimed CDM "prediction" for the BTFR is a gross
oversimplification of the complex galaxy-scale physics involved. We conclude
that the BTFR is currently untrustworthy as a test of CDM.Comment: 5 pages, 2 figures; minor revisions to match published versio
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