791 research outputs found
Inequalities for quantum skew information
We study quantum information inequalities and show that the basic inequality
between the quantum variance and the metric adjusted skew information generates
all the multi-operator matrix inequalities or Robertson type determinant
inequalities studied by a number of authors. We introduce an order relation on
the set of functions representing quantum Fisher information that renders the
set into a lattice with an involution. This order structure generates new
inequalities for the metric adjusted skew informations. In particular, the
Wigner-Yanase skew information is the maximal skew information with respect to
this order structure in the set of Wigner-Yanase-Dyson skew informations.
Key words and phrases: Quantum covariance, metric adjusted skew information,
Robertson-type uncertainty principle, operator monotone function,
Wigner-Yanase-Dyson skew information
Bridging inter-flow and intra-flow network coding in wireless mesh networks:From theory to implementation
The Protomedicato Tribunal and minorities in Castile at the end of the 17th century: the case of surgeon Roldán Solimán
[EN] This note aims to provide a small set of documents which report the vicissitudes of a North-African Muslim surgeon who tried to settle professionally during the late seventeenth century in the Kingdom of Castile. The four letters exchanged between the Royal Palace and the Castilian tribunal of the Protomedicato reveal that the Spanish king Charles II (1661-1700) resoluted supported the surgeon's aspirations, and the Protomedicato's concerted resistence to the royal will. These eloquent documents shed light on the history of the Castilian Protomedicato during the final years of the reign of the last Habsburg king in Spain by providing evidence about the role of this institution in the process of segregation/exclusion of ethnic minorities from the practice of health professions.[ES] El objeto de esta nota es presentar y editar una colección documental muy breve cuyo contenido nos informa sobre las vicisitudes de un cirujano musulmán norteafricano que a finales del siglo XVII busca su asentamiento profesional en la Corona de Castilla. Las cuatro cartas entre el Palacio Real y el Tribunal del Protomedicato, que se conservan en relación a este asunto, revelan tanto el decidido apoyo del Rey Carlos 11 (1665-1700) a las pretensiones del cirujano, como la fuerte resistencia ofrecida por el Protomedicato a la voluntad real. Esta expresiva documentación arroja luz en torno a la historia del Protomedicato en la Corona de Castilla durante los años finales del reinado del último Habsburgo en España, ilustrándonos sobre el papel entonces jugado por esta institución en el proceso de segregación/exclusión de las minorías étnicas, de la práctica de las ocupaciones sanitarias.Peer reviewe
A volume inequality for quantum Fisher information and the uncertainty principle
Let be complex self-adjoint matrices and let be a
density matrix. The Robertson uncertainty principle gives a bound for the quantum
generalized covariance in terms of the commutators . The right side
matrix is antisymmetric and therefore the bound is trivial (equal to zero) in
the odd case .
Let be an arbitrary normalized symmetric operator monotone function and
let be the associated quantum Fisher information. In
this paper we conjecture the inequality that gives a
non-trivial bound for any natural number using the commutators . The inequality has been proved in the cases by the joint efforts
of many authors. In this paper we prove the case N=3 for real matrices
Parametric improvement for the ingestion dose module of the European ARGOS and RODOS decision support systems
The European decision support systems ARGOS and RODOS rely on the ECOSYS model for prognoses of ingestion doses. ECOSYS needs an update of various parameter values to provide reliable estimates. This paper reports on some results of a Nordic initiative to derive parameter values that are specific to Nordic conditions, as well as to improve generic parameter values in ECOSYS, taking into account the host of useful measurement data accumulated since ECOSYS was created
A spatial judgement task to determine background emotional state in laboratory rats (Rattus norvegicus)
Humans experiencing different background emotional states display contrasting cognitive (e.g. judgement) biases when responding to ambiguous stimuli. We have proposed that such biases may be used as indicators of animal emotional state. Here, we use a spatial judgement task, in which animals are trained to expect food in one location and not another, to determine whether rats in relatively positive or negative emotional states respond differently to ambiguous stimuli of intermediate spatial location. We housed 24 rats with environmental enrichment for seven weeks. Enrichment was removed for half the animals prior to the start of training (‘U’: unenriched) to induce a relatively negative emotional state, whilst being left in place for the remaining rats (‘E’: enriched). After six training days, the rats successfully discriminated between the rewarded and unrewarded locations in terms of an increased latency to arrive at the unrewarded location, with no housing treatment difference. The subjects then received three days of testing in which three ambiguous ‘probe’ locations, intermediate between the rewarded and unrewarded locations, were introduced. There was no difference between the treatments in the rats’ judgement of two out of the three probe locations, the exception being when the ambiguous probe was positioned closest to the unrewarded location. This result suggests that rats housed without enrichment, and in an assumed relatively negative emotional state, respond differently to an ambiguous stimulus compared to rats housed with enrichment, providing evidence that cognitive biases may be used to assess animal emotional state in a spatial judgement task
Relic Neutralino Densities and Detection Rates with Nonuniversal Gaugino Masses
We extend previous analyses on the interplay between nonuniversalities in the
gaugino mass sector and the thermal relic densities of LSP neutralinos, in
particular to the case of moderate to large tan beta. We introduce a set of
parameters that generalizes the standard unified scenario to cover the complete
allowed parameter space in the gaugino mass sector. We discuss the physical
significance of the cosmologically preferred degree of degeneracy between
charginos and the LSP and study the effect this degree of degeneracy has on the
prospects for direct detection of relic neutralinos in the next round of dark
matter detection experiments. Lastly, we compare the fine tuning required to
achieve a satisfactory relic density with the case of universal gaugino masses,
as in minimal supergravity, and find it to be of a similar magnitude. The
sensitivity of quantifiable measures of fine-tuning on such factors as the
gluino mass and top and bottom masses is also examined.Comment: Uses RevTeX; 14 pages, 16 figure
Ground-state properties of tubelike flexible polymers
In this work we investigate structural properties of native states of a
simple model for short flexible homopolymers, where the steric influence of
monomeric side chains is effectively introduced by a thickness constraint. This
geometric constraint is implemented through the concept of the global radius of
curvature and affects the conformational topology of ground-state structures. A
systematic analysis allows for a thickness-dependent classification of the
dominant ground-state topologies. It turns out that helical structures,
strands, rings, and coils are natural, intrinsic geometries of such tubelike
objects
Time-Independent Gravitational Fields
This article reviews, from a global point of view, rigorous results on time
independent spacetimes. Throughout attention is confined to isolated bodies at
rest or in uniform rotation in an otherwise empty universe. The discussion
starts from first principles and is, as much as possible, self-contained.Comment: 47 pages, LaTeX, uses Springer cl2emult styl
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