Biomedical subjects

F Borondo

Publications and source records attributed to F Borondo.

12 recordsLinked to original sources

PubMed2001

Multifractal analysis of tori destruction in a molecular Hamiltonian system.

In this paper, an analysis of the phase space structure of the isomerizing molecular system LiNC/LiCN, using Poincaré surfaces of section and frequency analysis, is presented. The scaling structure of the frequency map in the chaotic region next to the regular part corresponding to the stable linear isomer LiNC is studied using multifractal analysis. This approach is a way to characterize quantitatively the complexity in the mechanism of the tori destruction in a molecular Hamiltonian system that exhibits soft chaos as the vibrational energy of the system increases.

Journal Article↗

PubMed2001

Localization properties of groups of eigenstates in chaotic systems.

In this paper we study in detail the localized wave functions defined in Phys. Rev. Lett. 76, 1613 (1994), in connection with the scarring effect of unstable periodic orbits in highly chaotic Hamiltonian system. These functions appear highly localized not only along periodic orbits but also on the associated manifolds. Moreover, they show in phase space the hyperbolic structure in the vicinity of the orbit, something that translates in configuration space into the structure induced by the corresponding self-focal points. On the other hand, the- quantum dynamics of these functions are also studied. Our results indicate that the probability density first evolves along the unstable manifold emanating from the periodic orbit, and localizes temporarily afterwards on only a few, short related periodic orbits. We believe that this type of study can provide some keys to disentangle the complexity associated with the quantum mechanics of these kind of systems, which permits the construction of a simple explanation in terms of the dynamics of a few classical structures.

Journal Article↗

PubMed2000

Beyond the first recurrence in scar phenomena

The scarring effect of short unstable periodic orbits up to times of the order of the first recurrence is well understood. Much less is known, however, about what happens past this short-time limit. By considering the evolution of a dynamically averaged wave packet, we show that the dynamics for longer times is controlled by only a few related short periodic orbits and their interplay.

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PubMed1996