arXiv subjects

Daniele Fournier-Prunaret

Publications and source records attributed to Daniele Fournier-Prunaret.

11 recordsLinked to original sources

arXiv2012

The bistable brain: a neuronal model with symbiotic interactions

In general, the behavior of large and complex aggregates of elementary components can not be understood nor extrapolated from the properties of a few components. The brain is a good example of this type of networked systems where some patterns of behavior are observed independently of the topology and of the number of coupled units. Following this insight, we have studied the dynamics of different aggregates of logistic maps according to a particular {\it symbiotic} coupling scheme that imitates the neuronal excitation coupling. All these aggregates show some common dynamical properties, concretely a bistable behavior that is reported here with a certain detail. Thus, the qualitative relationship with neural systems is suggested through a naive model of many of such networked logistic maps whose behavior mimics the waking-sleeping bistability displayed by brain systems. Due to its relevance, some regions of multistability are determined and sketched for all these logistic models.

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arXiv2010

Fractal Basins and Boundaries in 2D Maps inspired in Discrete Population Models

Two-dimensional maps can model interactions between populations. Despite their simplicity, these dynamical systems can show some complex situations, as multistability or fractal boundaries between basins that lead to remarkable pictures. Some of them are shown and explained here for three different 2D discrete models.

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arXiv2009

Regions of multistability in some low-dimensional logistic models with excitation type coupling

A naive model of many networked logistic maps with an excitation type coupling [Neural Networks, vol. 20, 102--108 (2007)], which is an extension of other low dimensional models, has been recently proposed to mimic the waking-sleeping bistability found in brain systems. Although the dynamics of large and complex aggregates of elementary components can not be understood nor extrapolated from the properties of a few components, some patterns of behavior could be conserved independently of the topology and of the number of coupled units. Following this insight, we have collected several of those systems where a few logistic maps are coupled under a similar mutual excitation scheme. The regions of bi- and multistability of these systems are sketched and reported.

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arXiv2007

Bistability: a common feature in some "aggregates" of logistic maps

As it was argued by Anderson [Science 177, 393 (1972)], the "reductionist" hypothesis does not by any means imply a "constructionist" one. Hence, in general, the behavior of large and complex aggregates of elementary components can not be understood nor extrapolated from the properties of a few components. Following this insight, we have simulated different "aggregates" of logistic maps according to a particular coupling scheme. All these aggregates show a similar pattern of dynamical properties, concretely a bistable behavior, that is also found in a network of many units of the same type, independently of the number of components and of the interconnection topology. A qualitative relationship with brain-like systems is suggested.

nlin.AO↗

arXiv2006

Three Logistic Models for the Ecological and Economic Interactions: Symbiosis, Predator-Prey and Competition

If one isolated species (corporation) is supposed to evolve following the logistic mapping, then we are tempted to think that the dynamics of two species (corporations) can be expressed by a coupled system of two discrete logistic equations. As three basic relationships between two species are present in Nature, namely symbiosis, predator-prey and competition, three different models are obtained. Each model is a cubic two-dimensional discrete logistic-type equation with its own dynamical properties: stationary regime, periodicity, quasi-periodicity and chaos. We also propose that these models could be useful for thinking in the different interactions happening in the economic world, as for instance for the competition and the collaboration between corporations. Furthermore, these models could be considered as the basic ingredients to construct more complex interactions in the ecological and economic networks.

nlin.AO↗

arXiv2005

Periodic and Chaotic Events in a Discrete Model of Logistic Type for the Competitive Interaction of Two Species

Two symmetrically coupled logistic equations are proposed to mimic the competitive interaction between two species. The phenomena of coexistence, oscillations and chaos are present in this cubic discrete system. This work, together with two other similar ones recently published by the authors, completes a triptych dedicated to the two-species relationships present in Nature, namely the symbiosis, the predator-prey and the competition. These models can be used as basic ingredients to build up more complex interactions in the ecological networks.

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arXiv2005

Route to Chaos in Three-Dimensional Maps of Logistic Type

A route to chaos is studied in 3-dimensional maps of logistic type. Mechanisms of period doubling for invariant closed curves (ICC) are found for specific 3-dimensional maps. These bifurcations cannot be observed for ICC in the 2-dimensional case. When the parameter of the system is modified, localized oscillations occur on the ICC that give rise to weakly chaotic rings, then to chaotic attractors, which finally disappear by contact bifurcations. These maps can be considered as models for the symbiotic interaction of three species.

nlin.CD↗

arXiv2004

Indirect Allee Effect, Bistability and Chaotic Oscillations in a Predator-Prey Discrete Model of Logistic Type

A cubic discrete coupled logistic equation is proposed to model the predator-prey problem. The coupling depends on the population size of both species and on a positive constant $λ$, which could depend on the prey reproduction rate and on the predator hunting strategy. Different dynamical regimes are obtained when $λ$ is modified. For small $λ$, the species become extinct. For a bigger $λ$, the preys survive but the predators extinguish. Only when the prey population reaches a critical value then predators can coexist with preys. For increasing $λ$, a bistable regime appears where the populations apart of being stabilized in fixed quantities can present periodic, quasiperiodic and chaotic oscillations. Finally, bistability is lost and the system settles down in a steady state, or, for the biggest permitted $λ$, in an invariant curve. We also present the basins for the different regimes. The use of the critical curves lets us determine the influence of the zones with different number of first rank preimages in the bifurcation mechanisms of those basins.

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arXiv2004

Complex Behaviour in a Discrete Coupled Logistic Model for the Symbiotic Interaction of Two Species

A symmetrical cubic discrete coupled logistic equation is proposed to model the symbiotic interaction of two isolated species. The coupling depends on the population size of both species and on a positive constant $λ$, named the mutual benefit. Different dynamical regimes are obtained when the mutual benefit is modified. For small $λ$, the species become extinct. For increasing $λ$, the system stabilizes in a synchronized state or oscillates in a 2 periodic orbit. For the greatest permitted values of $λ$, the dynamics evolves into a quasiperiodic, into a chaotic scenario or into extinction. The basins for these regimes are visualized as coloured figures on the plane. These patterns suffer different change as consequence of basins' bifurcations. The use of the critical curves let us to determine the influence of the zones with different number of first rank preimages in those bifurcation mechanisms.

nlin.AO↗

arXiv2003

Basin Bifurcations in a Two-Dimensional Logistic Map

Previous works have been devoted to the study of two-dimensional noninvertible maps, obtained using a coupling between one-dimensional logistic maps. This paper is devoted to the study of a specific one, in order to complete previous results (Ref. 5 and 7), regarding the evolution of basins and attractors, when considering the tool of critical manifolds.

nlin.CD↗

arXiv2002

Complex patterns on the plane: different types of basin fractalization in a two-dimensional mapping

Basins generated by a noninvertible mapping formed by two symmetrically coupled logistic maps are studied when the only parameter λof the system is modified. Complex patterns on the plane are visualised as a consequence of basins' bifurcations. According to the already established nomenclature in the literature, we present the relevant phenomenology organised in different scenarios: fractal islands disaggregation, finite disaggregation, infinitely disconnected basin, infinitely many converging sequences of lakes, countable self-similar disaggregation and sharp fractal boundary. By use of critical curves, we determine the influence of zones with different number of first rank preimages in the mechanisms of basin fractalization.

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