173 research outputs found
Complex structures in generalized small worlds
We propose a generalization of small world networks, in which the
reconnection of links is governed by a function that depends on the distance
between the elements to be linked. An adequate choice of this function lets us
control the clusterization of the system. Control of the clusterization, in
turn, allows the generation of a wide variety of topologies.Comment: 4 pages, 6 figures, RevTe
Globally coupled maps with asynchronous updating
We analyze a system of globally coupled logistic maps with asynchronous
updating. We show that its dynamics differs considerably from that of the
synchronous case. For growing values of the coupling intensity, an inverse
bifurcation cascade replaces the structure of clusters and ordering in the
phase diagram. We present numerical simulations and an analytical description
based on an effective single-element dynamics affected by internal
fluctuations. Both of them show how global coupling is able to suppress the
complexity of the single-element evolution. We find that, in contrast to
systems with synchronous update, internal fluctuations satisfy the law of large
numbers.Comment: 7 pages, submitted to PR
Extremal Coupled Map Lattices
We propose a model for co-evolving ecosystems that takes into account two
levels of description of an organism, for instance genotype and phenotype.
Performance at the macroscopic level forces mutations at the microscopic level.
These, in turn, affect the dynamics of the macroscopic variables. In some
regions of parameter space, the system self-organises into a state with
localised activity and power law distributions.Comment: 4 RevTeX pages, 3 eps figures. Uses psfig.sty. To be published in The
European Physical Journal B (1999
Imitation dynamics in a game of traffic
We study a model of traffic where drivers adopt different behavioral
strategies. These can be cooperative or defective according to a driver abiding
or not by a traffic rule. Drivers can change their strategy by imitating the
majority, with a rule that depends on the strategies with which they have
interacted. These interactions occur at intersections, where vehicles pay a
temporal cost according to their strategy. We analyze the conditions under
which different strategy compositions represent an advantage in the system
velocity. We found that the cooperators' mean speed is higher than the
defectors' even when the vehicle density is large. However, defectors can
obtain benefits in their mean speed when they are a minority in an essentially
cooperative population. The presence of a core of educated drivers, who persist
firmly in a cooperative behavior, optimizes the speed in the system, especially
for intermediate values of vehicular density and higher temporal costs
Peculiar: Centaurus A
He aquí Centaurus A, también conocida como NGC 5128. Es una de las galaxias más brillantes, una de las joyitas del cielo austral. Los astrónomos clasifican a esta galaxia como “peculiar”. Aún para un ocasional astrónomo aficionado, una foto como ésta no deja lugar a dudas: es peculiarFil: Abramson, Guillermo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Serendipitous observation of a coronal mass ejection during the total solar eclipse of 14 December 2020
We report observations of the total solar eclipse of 14 December 2020, during which a coronal mass ejection was seen to propagate. A comprehensive set of photographs covering a high dynamic range of exposure enabled characterization of its dimensions. Displacement of the front can be seen during the few minutes of totality.Fil: Abramson, Guillermo. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentin
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