Mendoza, C. (Cristian)

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    Anomalous synchronization of spatially extended chaotic systems in the presence of asymmetric coupling
    (2005) Boccaletti, S. (S.); Mendoza, C. (Cristian); Bragard, J. (Jean)
    Communicated by Werner Ebeling and Bernardo Spagnolo This paper describes the e ects of an asymmetric coupling in the synchronization of two spatially extended systems. Namely, we report the consequences induced by the presence of asymmetries in the coupling con guration of a pair of one-dimensional elds obeying Complex Ginzburg Landau equations. While synchronization always occurs for large enough coupling strengths, asymmetries have the e ect of enhancing synchronization and play a crucial role in setting the threshold for the appearance of the synchronized dynamics, as well as in selecting the statistical and dynamical properties of the synchronized motion. We discuss the process of synchronization in the presence of asymmetries by using some analytic expansions valid for a regime of soft spatial temporal chaos (i.e. phase turbulence regime). The in uence of phase singularities that break the validity of the analysis is also discussed.
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    Synchronization of spatially extended chaotic systems in the presence of asymmetric coupling
    (2004) Boccaletti, S. (S.); Mendoza, C. (Cristian); Hentschel, H. (H.); Bragard, J. (Jean); Mancini-Maza, H. L. (Hector Luis)
    In a recent paper [Phys. Rev. Lett. 91, 064103 (2003)] we described the effects of asymmetric coupling configurations on the synchronization of spatially extended systems. In this paper, we report the consequences induced by the presence of asymmetries in the coupling scheme on the synchronization process of a pair of one-dimensional fields obeying complex Ginzburg-Landau equations. While synchronization always occurs for large enough coupling strengths, asymmetries have the effect of enhancing synchronization and play a crucial role in setting the threshold for the appearance of the synchronized dynamics, as well as in selecting the statistical and dynamical properties of the synchronized motion. We analyze the process of synchronization in the presence of asymmetries when the dynamics is affected by the presence of phase singularities, and show that defects tend to anchor one system to the other. In addition, asymmetry controls the number of synchronized defects that are present in the dynamics. Possible consequences of such asymmetry induced effects in biological and natural systems are discussed.
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    Pinning control of chaos in the LCLV device
    (2007) Ramazza, P.L. (Pier Luigi); Boccaletti, S. (S.); Mendoza, C. (Cristian); Bragard, J. (Jean); Martinez-Mardones, J. (J.)
    We study the feasibility of transferring data in an optical device by using a limited number of parallel channels. By applying a spatially localized correcting term to the evolution of a liquid crystal light valve in its spatio{ temporal chaotic regime, we are able to restore the dynamics to a speci ed target pattern. The system is controlled in a nite time. The number and position of pinning points needed to attain control is also investigated.
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    Synchronization of spatially extended chaotic systems with asymmetric coupling
    (2005) Boccaletti, S. (S.); Mendoza, C. (Cristian); Bragard, J. (Jean)
    In this paper, we report the consequences induced by the presence of asymmetries in the coupling scheme on the synchronization process of a pair of one-dimensional complex fields obeying Complex Ginzburg Landau equations. While synchronization always occurs for large enough coupling strengths, asymmetries have the effect of modifying synchronization thresholds and play a crucial role in selecting the statistical and dynamical properties of the highly coupled synchronized motion. Possible consequences of such symmetry induced effects in biological and natural systems are discussed.
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    Defect-enhanced anomaly in frequency synchonization of asymmetrically coupled spatially extended systems
    (2005) Montbrio, E. (E.); Boccaletti, S. (S.); Mendoza, C. (Cristian); Blasius, B. (B.); Bragard, J. (Jean)
    We analytically establish and numerically show that anomalous frequency synchronization occurs in a pair of asymmetrically coupled chaotic space extended oscillators. The transition to anomalous behaviors is crucially dependent on asymmetries in the coupling configuration, while the presence of phase defects has the effect of enhancing the anomaly in frequency synchronization with respect to the case of merely time chaotic oscillators.
  • Pobreza material y antropológica: una aproximación desde la Doctrina Social de la Iglesia
    (Servicio de Publicaciones de la Universidad de Navarra, 2020) Mendoza, C. (Cristian)
    This paper summarizes some of the principal perspectives to understand poverty. I take into consideration some of the initiatives of the World Economic Forum and the United Nations, as well as some of the academia and specific research centers in this field. The scope of this article is to approach poverty from the perspective of Catholic Social Doctrine to underline that this problem is more than a material issue, it is a moral and anthropologic problem. When understood in terms of a moral and anthropologic problem, poverty is translated as violence, corruption, damage to life and to people in need etc. The point of this paper is to show that anthropologic poverty always gives place to economic poverty, but not the other way around. Economic poverty does not always generate anthropologic poverty. This is because families with few economic resources can actually live on values that allow them to have a good life. In this paper I take into consideration some of the general solutions currently given to poverty, stressing the importance of multiplying human relationships in benefit of a greater social knowledge. The conclusions of this paper explain that people in a specific society reach development not when all of them do the same thing, but when each person is able to undertake their specific task in the best possible way.
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    Chaos suppression through asymmetric coupling
    (2007) Boccaletti, S. (S.); Mendoza, C. (Cristian); Vidal, G. (Gerard); Bragard, J. (Jean); Mancini-Maza, H. L. (Hector Luis)
    We study pairs of identical coupled chaotic oscillators. In particular, we have used Roessler in the funnel and no funnel regimes , Lorenz, and four-dimensional chaotic Lotka-Volterra models. In all four of these cases, a pair of identical oscillators is asymmetrically coupled. The main result of the numerical simulations is that in all cases, specific values of coupling strength and asymmetry exist that render the two oscillators periodic and synchronized. The values of the coupling strength for which this phenomenon occurs is well below the previously known value for complete synchronization. We have found that this behavior exists for all the chaotic oscillators that we have used in the analysis. We postulate that this behavior is presumably generic to all chaotic oscillators. In order to complete the study, we have tested the robustness of this phenomenon of chaos suppression versus the addition of some Gaussian noise. We found that chaos suppression is robust for the addition of finite noise level. Finally, we propose some extension to this research.
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    Convective instabilities of synchronization manifolds in spatially extended systems
    (2004) Politi, A. (A.); Boccaletti, S. (S.); Mendoza, C. (Cristian)
    We study the stability properties of anticipating synchronization in an open chain of unidirectionally coupled identical chaotic oscillators. Despite being absolutely stable, the synchronization manifold is unstable to propagating perturbations. We analyze and characterize such instabilities drawing a qualitative and quantitative comparison with the convective instabilities typical of spatially extended systems.