77 research outputs found
La visión de las culturas no occidentales sobre la legitimidad del derecho internacional contemporáneo
Existence of naked singularities in Brans-Dicke theory of gravitation. An analytical and numerical study
Within the framework of the scalar-tensor models of gravitation and by
relying on analytical and numerical techniques, we establish the existence of a
class of spherically symmetric spacetimes containing a naked singularity. Our
result relies on and extends a work by Christodoulou on the existence of naked
singularities for the Einstein-scalar field equations. We establish that a key
parameter in Christodoulou's construction couples to the Brans-Dicke field and
becomes a dynamical variable, which enlarges and modifies the phase space of
solutions. We recover analytically many properties first identified by
Christodoulou, in particular the loss of regularity (especially at the center),
and then investigate numerically the properties of these spacetimes.Comment: 26 pages, PACS numbers: 04.20.Dw, 04.25.dc, 04.50.K
A Particle-based Multiscale Solver for Compressible Liquid-Vapor Flow
To describe complex flow systems accurately, it is in many cases important to
account for the properties of fluid flows on a microscopic scale. In this work,
we focus on the description of liquid-vapor flow with a sharp interface between
the phases. The local phase dynamics at the interface can be interpreted as a
Riemann problem for which we develop a multiscale solver in the spirit of the
heterogeneous multiscale method, using a particle-based microscale model to
augment the macroscopic two-phase flow system. The application of a microscale
model makes it possible to use the intrinsic properties of the fluid at the
microscale, instead of formulating (ad-hoc) constitutive relations
A comparison of hyperbolic solvers II: ausm-type and Hybrid Lax-Wendroff-Lax-Friedrichs methods for two-phase flows
Equilibrium configurations from gravitational collapse
We develop here a new procedure within Einstein's theory of gravity to
generate equilibrium configurations that result as the final state of
gravitational collapse from regular initial conditions. As a simplification, we
assume that the collapsing fluid is supported only by tangential pressure. We
show that the equilibrium geometries generated by this method form a subset of
static solutions to the Einstein equations, and that they can either be regular
or develop a naked singularity at the center. When a singularity is present,
there are key differences in the properties of stable circular orbits relative
to those around a Schwarzschild black hole with the same mass. Therefore, if an
accretion disk is present around such a naked singularity it could be
observationally distinguished from a disk around a black hole.Comment: 13 pages, 3 figure. Replaced with published version, several changes
made according to referee's advis
Exploring synergies between human rights and public health ethics: A whole greater than the sum of its parts
<p>Abstract</p> <p>Background</p> <p>The fields of human rights and public health ethics are each concerned with promoting health and elucidating norms for action. To date, however, little has been written about the contribution that these two justificatory frameworks can make together. This article explores how a combined approach may make a more comprehensive contribution to resolving normative health issues and to advancing a normative framework for global health action than either approach made alone. We explore this synergy by first providing overviews of public health ethics and of international human rights law relevant to health and, second, by articulating complementarities between human rights and public health ethics.</p> <p>Discussion</p> <p>We argue that public health ethics can contribute to human rights by: (a) reinforcing the normative claims of international human rights law, (b) strengthening advocacy for human rights, and (c) bridging the divide between public health practitioners and human rights advocates in certain contemporary health domains. We then discuss how human rights can contribute to public health ethics by contributing to discourses on the determinants of health through: (a) definitions of the right to health and the notion of the indivisibility of rights, (b) emphasis on the duties of states to progressively realize the health of citizens, and (c) recognition of the protection of human rights as itself a determinant of health. We also discuss the role that human rights can play for the emergent field of public health ethics by refocusing attention on the health and illness on marginalized individuals and populations.</p> <p>Summary</p> <p>Actors within the fields of public health, ethics and human rights can gain analytic tools by embracing the untapped potential for collaboration inherent in such a combined approach.</p
Between history and values: A study on the nature of interpretation in international law
My thesis discusses the place of evaluative judgements in the interpretation of general international law. It concentrates on two questions. First, whether it is possible to interpret international legal practices without making an evaluative judgement about the point or value that provides the best justification of these practices. Second, whether the use of evaluative judgements in international legal interpretation threatens to undermine the objectivity of international law, the neutrality of international lawyers or the consensual and voluntary basis of the international legal system. I answer both questions in the negative. As regards the first, I argue that international legal practice has an interpretive structure, which combines appeals to the history of international practice with appeals to the principles and values that these practices are best understood as promoting. This interpretive structure is apparent not only in the claims of international lawyers about particular rules of international law (here I use the rule of estoppel as an example) but also in the most basic intuitions of international theorists about the theory and sources of general international law. I then argue that some popular concerns to the effect that the exercise of evaluation in the interpretation of international law will undermine the coherence or the usefulness of the discipline are generally unwarranted. The fact that international legal practice has an interpretive structure does not entail that propositions of international law are only subjectively true, that the interpreter enjoys license to manipulate their meaning for self-serving purposes, or that international law will collapse under the weight of irresolvable disagreements, divisions and conflicts about its proper interpretation
Post-annealed silicon nanocrystal formation on substoichiometric SiO
In this work is presented a detailed physicochemical, structural and optical
characterization of SiOxNy thin films. The films deposited using PECVD
in SiH4-N2O-He discharges were thermally annealed at 1273 K for 1 hour
in ambient nitrogen. The film stochiometry was measured by Rutherford
Backscattering Spectroscopy. The chemical composition was dominated by
silicon suboxide containing some Si-N and Si-H bonds. Raman scattering measurements
suggest the formation of nanocrystallite silicon in the annealed films. The
Raman observation is strongly supported by Transmission Electron Microscopy
analysis which shows a high density of silicon nanocrystals, having a mean
radius ranging between 3 and 6 nm. Using Spectroscopic Ellipsometry, we
discussed the dielectric function evolution as a function of the deposition
parameters
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