5 research outputs found
Optimization as a result of the interplay between dynamics and structure
In this work we study the interplay between the dynamics of a model of
diffusion governed by a mechanism of imitation and its underlying structure.
The dynamics of the model can be quantified by a macroscopic observable which
permits the characterization of an optimal regime. We show that dynamics and
underlying network cannot be considered as separated ingredients in order to
achieve an optimal behavior.Comment: 12 pages, 4 figures, to appear in Physica
Nonequilibrium phase transition in a model for the propagation of innovations among economic agents
We characterize the different morphological phases that occur in a simple
one-dimensional model of propagation of innovations among economic agents [X.\
Guardiola, {\it et. al.}, Phys. Rev E {\bf 66}, 026121 (2002)]. We show that
the model can be regarded as a nonequilibrium surface growth model. This allows
us to demonstrate the presence of a continuous roughening transition between a
flat (system size independent fluctuations) and a rough phase (system size
dependent fluctuations). Finite-size scaling studies at the transition strongly
suggest that the dynamic critical transition does not belong to directed
percolation and, in fact, critical exponents do not seem to fit in any of the
known universality classes of nonequilibrium phase transitions. Finally, we
present an explanation for the occurrence of the roughening transition and
argue that avalanche driven dynamics is responsible for the novel critical
behavior
Nonequilibrium phase transition in a model for the propagation of innovations among economic agents
We characterize the different morphological phases that occur in a simple one-dimensional model of propagation of innovations among economic agents [X. Guardiola et al., Phys. Rev E 66, 026121 (2002)]. We show that the model can be regarded as a nonequilibrium surface growth model. This allows us to demonstrate the presence of a continuous roughening transition between a flat (system size independent fluctuations) and a rough phase (system size dependent fluctuations). Finite-size scaling studies at the transition strongly suggest that the dynamic critical transition does not belong to directed percolation and, in fact, critical exponents do not seem to fit in any of the known universality classes of nonequilibrium phase transitions. Finally, we present an explanation for the occurrence of the roughening transition and argue that avalanche driven dynamics is responsible for the novel critical behavior
Synchronization, diversity, and topology of networks of integrate and fire oscillators
We study synchronization dynamics of a population of pulse-coupled oscillators. In particular, we focus our attention on the interplay between topological disorder and synchronization features of networks. First, we analyze synchronization time T in random networks, and find a scaling law which relates T to network connectivity. Then, we compare synchronization time for several other topological configurations, characterized by a different degree of randomness. The analysis shows that regular lattices perform better than a disordered network. This fact can be understood by considering the variability in the number of links between two adjacent neighbors. This phenomenon is equivalent to having a nonrandom topology with a distribution of interactions and it can be removed by an adequate local normalization of the couplings