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Imagining Alternatives? Latin American Scholarship on International Economic Law and the Global Economic Order
This Article analyzes the role of Latin American international economic law scholarship within the global economic order. Many of the problems that Latin Americans face today relate to the global economy, such as labor conditions, access to medicine, and the use of natural resources, among others. The discussion of these problems, however, seldom recognizes the role of international economic law scholarship. Although the knowledge created by this scholarship may not completely explain why States actively behave in a certain way, it can serve to explain why they may refrain from certain actions. This Article argues that scholarship on international economic law plays a crucial role in the creation and reproduction of the current global economic order. If this claim is correct, regional scholarship can do more for Latin America than serving the advisory and litigation needs of States. By recognizing its role in constituting the global economic order, international economic law scholarship can promote alternative theories and practices that may help Latin America and its people find their place in the global economy
Fast optimization of parametrized quantum optical circuits
Parametrized quantum optical circuits are a class of quantum circuits in
which the carriers of quantum information are photons and the gates are optical
transformations. Classically optimizing these circuits is challenging due to
the infinite dimensionality of the photon number vector space that is
associated to each optical mode. Truncating the space dimension is unavoidable,
and it can lead to incorrect results if the gates populate photon number states
beyond the cutoff. To tackle this issue, we present an algorithm that is orders
of magnitude faster than the current state of the art, to recursively compute
the exact matrix elements of Gaussian operators and their gradient with respect
to a parametrization. These operators, when augmented with a non-Gaussian
transformation such as the Kerr gate, achieve universal quantum computation.
Our approach brings two advantages: first, by computing the matrix elements of
Gaussian operators directly, we don't need to construct them by combining
several other operators; second, we can use any variant of the gradient descent
algorithm by plugging our gradients into an automatic differentiation framework
such as TensorFlow or PyTorch. Our results will find applications in quantum
optical hardware research, quantum machine learning, optical data processing,
device discovery and device design.Comment: 21 pages, 10 figure
Broadband pseudothermal states with tunable spectral coherence generated via nonlinear optics
It is well known that the reduced state of a two-mode squeezed vacuum state
is a thermal state---i.e. a state whose photon-number statistics obey a
geometric distribution. More exotic \emph{broadband} states can be realized as
the reduced state of two spectrally-entangled beams generated using nonlinear
optics. We show that these broadband "pseudothermal" states are tensor products
of states in spectral Schmidt modes, whose photon-number statistics obey a
geometric distribution. We study the spectral and temporal coherence properties
of these states and show that their spectral coherence can be tuned---from
perfect coherence to complete incoherence---by adjusting the pump spectral
width. In the limit of a cw pump, these states are tensor products of true
thermal states, but with different temperatures at each frequency. This could
be an interesting state of light for investigating the interplay between
spectral, temporal, and photon-number coherences.Comment: 6 pages main text, 1 full-page figure (12 pages total including
reference and appendices
The importance of individual heterogeneity in the decomposition of measures of socioeconomic inequality in health: An approach based on quantile regression
This paper shows how recently developed regression-based methods for the decomposition of health inequality can be extended to incorporate individual heterogeneity in the responses of health to the explanatory variables. We illustrate our method with an application to the Canadian NPHS of 1994. Our strategy for the estimation of heterogeneous responses is based on the quantile regression model. The results suggest that there is an important degree of heterogeneity in the association of health to explanatory variables which, in turn, accounts for a substantial percentage of inequality in observed health. A particularly interesting finding is that the marginal response of health to income is zero for healthy individuals but positive and significant for unhealthy individuals. The heterogeneity in the income response reduces both overall health inequality and income related health inequality.Health inequalities, unobserved heterogeneity, quantile regression
Middle Darriwilian conodont zones in the uppermost San Juan limestone and the lower member of the Las Aguaditas formation, central Precordillera of San Juan, Argentina
The geological province of Precordillera is located in western Argentina. It extends 450 km meridionally and 110 km from east to west (Fig. 1) (Furque and Cuerda, 1979). The Lower Paleozoic stratigraphy is characterized by a thick succession of Cambro-Ordovician limestones, which were deposited in platform environments and interdigitate with clastic slope deposits toward the west (Keller et al., 1993; Astini, 1995).Fil: Feltes, Nicolás Alexis. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Museo de Paleontología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Albanesi, Guillermo Luis. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Museo de Paleontología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones en Ciencias de la Tierra. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones en Ciencias de la Tierra; ArgentinaFil: Bergström, S. M.. Ohio State University; Estados Unido
Self-calibrating tomography for multi-dimensional systems
We present a formalism for self-calibrating tomography of arbitrary
dimensional systems. Self-calibrating quantum state tomography was first
introduced in the context of qubits, and allows the reconstruction of the
density matrix of an unknown quantum state despite incomplete knowledge of the
unitary operations used to change the measurement basis. We show how this can
be generalized to qudits, i.e. d-level systems, and provide a specific example
for a V-type three-level atomic system whose transition dipole moments are not
known. We show that it is always possible to retrieve the unknown state and
process parameters, except for a set of zero measure in the state-parameter
space.Comment: Revised version. 9 pages, 3 figure
'Getting out of the closet': Scientific authorship of literary fiction and knowledge transfer
Some scientists write literary fiction books in their spare time. If these
books contain scientific knowledge, literary fiction becomes a mechanism of
knowledge transfer. In this case, we could conceptualize literary fiction as
non-formal knowledge transfer. We model knowledge transfer via literary fiction
as a function of the type of scientist (academic or non-academic) and his/her
scientific field. Academic scientists are those employed in academia and public
research organizations whereas non-academic scientists are those with a
scientific background employed in other sectors. We also distinguish between
direct knowledge transfer (the book includes the scientist's research topics),
indirect knowledge transfer (scientific authors talk about their research with
cultural agents) and reverse knowledge transfer (cultural agents give
scientists ideas for future research). Through mixed-methods research and a
sample from Spain, we find that scientific authorship accounts for a
considerable percentage of all literary fiction authorship. Academic scientists
do not transfer knowledge directly so often as non-academic scientists, but the
former engage into indirect and reverse transfer knowledge more often than the
latter. Scientists from History stand out in direct knowledge transfer. We draw
propositions about the role of the academic logic and scientific field on
knowledge transfer via literary fiction. We advance some tentative conclusions
regarding the consideration of scientific authorship of literary fiction as a
valuable knowledge transfer mechanism.Comment: Paper published in Journal of Technology Transfe
Non-Hermitian engineering for brighter broadband pseudothermal light
We show that non-Hermitian engineering can play a positive role in quantum
systems. This is in contrast to the widely accepted notion that optical losses
are a foe that must be eliminated or, at least, minimized. We take advantage of
the interplay between nonlinear interactions and loss to show that
spectral-loss engineering can relax phase-matching conditions, enabling
generation of broadband pseudothermal states at new frequencies. This opens the
door for utilizing the full potential of semiconductor materials that exhibit
giant nonlinearities but lack the necessary ingredients for achieving
quasi-phase matching. This in turn may pave the way for building on-chip
quantum light sources.Comment: 11 pages (6 pages main text); 4 figure
Entanglement reduction induced by geometrical confinement in polymer thin films
We report simulation results on melts of entangled linear polymers confined
in a free-standing thin film. We study how the geometric constraints imposed by
the confinement alter the entanglement state of the system compared to the
equivalent bulk system using various observables. We find that the confinement
compresses the chain conformation uniaxially, decreasing the volume pervaded by
the chain, which in turn reduces the number of the accessible inter-chain
contact that could lead to entanglements. This local and non-uniform effect
depends on the position of the chain within the film. We also test a recently
presented theory that predicts how the number of entanglements decreases with
geometrical confinement.Comment: 28 pages, 10 figure
Branching rate expansion around annihilating random walks
We present some exact results for branching and annihilating random walks. We
compute the nonuniversal threshold value of the annihilation rate for having a
phase transition in the simplest reaction-diffusion system belonging to the
directed percolation universality class. Also, we show that the accepted
scenario for the appearance of a phase transition in the parity conserving
universality class must be improved. In order to obtain these results we
perform an expansion in the branching rate around pure annihilation, a theory
without branching. This expansion is possible because we manage to solve pure
annihilation exactly in any dimension.Comment: 5 pages, 5 figure
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