Institute for Biocomputation and
Physics of Complex Systems

Complex Networks and Society

Responsible

Dr. Yamir Moreno Vega

People involved

From BIFI:

Jesús Gómez Gardeñes
Pablo Echenique
Prof. Amalio F. Pacheco
Prof. Luis Mario Floría
Prof. Juan José Mazo
Prof. Javier B. Gómez

From other Institutions:

Dr. Maziar Nekovee (BT Research Labs, U.K)
Dr. Alexei Vázquez (Notre Dame, USA)
Prof. Alessandro Vespignani (Bloomigton Univ. USA)
Dr. Romualdo Pastor-Satorras (UPC, Barcelona, Spain)
Dr. Vito Latora (Univ. Catania, Italy)
Dr. Enzo Marinari (Univ. Roma I, Italy)
Dr. Stefano Boccaletti (IOA, Florence, Italy)
Prof. Albert Díaz-Guilera (Univ. Barcelona, Spain)

Complex Networks and Society

For many years, scientists have been studying the physics world through its fundamental components. Modern science has certainly achieved many successes and nowadays we are close to comprehend almost everything there is to know about fundamental principles. At the same time, we have also been able to recognize that there are many different ways to put the system's constituents back together. Recently, a string of important discoveries has begun to expose a common pattern of self-organization that emerges again and again in otherwise seemingly diverse systems. Somehow, the interactions among species, individuals, units, routers, etc in real physical, biological, social and communication systems generate networks that share many topological features. They are called Complex Networks (for a review, see Nature 410, 268 (2001)). The aim of the research carried out is therefore to study how networks emerge, what they look like, how they evolve and how we can take advantage of our knowledge of them. Since the seminal work by Barabasi et al (Science 286, 509 (1999)), scale-free networks (those without a typical number of links) have been widely found in Nature. Besides, it has been shown that they have unique mathematical and physical properties. For example, they are very robust to random failures but, at the same time, fragile to targeted attacks (Nature 406, 378 (2000); PRL 85, 4626 (2000)). On the other hand, studies on how diseases spread across these networks (PRL 86, 3200 (2000); EPJB 26, 521 (2002)) show that epidemiological standard concepts should be re-analyzed. Another research trend includes the use of complex networks to uncover unknown interaction maps and functions, as could be the case of protein networks (Nature 407, 651 (2000)). This field has the additional challenge of finding alternative drug designing approaches to treat genetic diseases.

Our research group is devoted to the study of the structure and dynamics of complex networks in fields such as: biological, social and communication networks. For instance, in the context of technological networks, we can study the temporal and geographical evolution of these networks, which allows us to unravel regularities in their formation (in general, proportional to socio-economics indexes). On the other hand, once the architecture of these networks is known, several relevant processes for the efficient exploitation of them and the design of new algorithms and networked systems can be modeled.

During the last several years, the specific problems studied in our group include:

- Analysis of the topology of real networks and of models on top of them.

- Study of nonlinear dynamical systems coupled to complex structures in order to model biological processes such as: metabolisms and gene expression.

- Transport processes and diffusion with applications to communication networks and technologies.

- Handling of traffic information in communication networks and development of new routing algorithms.

- Dynamics of virus and rumors propagation looking for the analogies between biological and technological processes.

- Synchronization phenomena and emergence of collective behaviors such as cooperation in biological systems and mainly in social environments.

- Different processes and optimization algorithms.

- Structure and dynamics of social systems.

Some publications on the subject (for a full list follow this link)

1.Local versus Global Knowledge in the Barabási-Albert Scale-Free Network Model. PHYSICAL REVIEW E, 69, 037103 (2004).

2.Efficiency and Reliability of Epidemic Data Dissemination in Complex Networks. PHYSICAL REVIEW E, 69, 055101R (2004).

3.Modelling and Simulation of the Impact of Network Topology on Epidemic Protocols. Proceedings of ICCS2004.

4.Dynamics of Rumor Spreading in Complex Networks. PHYSICAL REVIEW E, 69, 066130 (2004).

5.Synchronization of Kuramoto Oscillators in Complex Networks. EUROPHYSICS LETTERS, 68, 603 (2004).

6.Improved Routing Strategies for Internet Traffic Delivery. PHYSICAL REVIEW E, 70, 056105 (2004).

7.Fitness for Synchronization of Network Motifs. PHYSICA A, 343, 279 (2004).

8.Distance-d Covering Problems in Scale-Free Networks with Degree Correlations. PHYSICAL REVIEW E, 71, 035102(R) (2005).

9.On the Robustness of Complex Heterogeneous Gene Expression Networks. BIOPHYSICAL CHEMISTRY, 115, 225 (2005).

10.Michaelis-Menten Dynamics in Complex Heterogeneous Networks. PHYSICA A, 352, 265 (2005).

11.Thresholds for Epidemic Outbreaks in Finite Scale-Free Networks. MATHEMATICAL BIOSCIENCES AND ENGINEERING, 2, 317 (2005).

12.Dynamics of Jamming Transitions in Complex networks. EUROPHYSICS LETTERS, 71, 325 (2005).

Conferences (last two years)

1.Modelling and Simulation of the Impact of Network Topology on Epidemic Protocols. Fifth International Conference on Complex Systems (ICCS2004), Boston, MA, USA, 16-21 May 2004. Invited Conference.

2.Dynamics of a Complex Gene Network: Chaotic, Periodic and Steady States. First International Conference, Biology after the Genome: A Physical View, BIFI, Zaragoza, Spain, 2004. Póster.

3.Synchronization of Coupled Oscillators in Scale-Free Networks. First International Conference, Biology after the Genome: A Physical View, BIFI, Zaragoza, Spain, 2004. Póster.

4.The Structure and Function of Complex Networks: II Congreso Nacional del BIFI, Zaragoza, Spain, 2005. Conferencia Invitada.

5.Covering problems and traffic handling in Complex Networks. Workshop on the Structure and Function of Complex Networks, International Centre for Theoretical Physics, Trieste, Italy. 2005. Conferencia Invitada.

6.Dynamics of Complex Networks. FISES-05, Madrid, Spain, 2005. Conferencia Invitada.

7.The spreading of epidemics and rumours in complex networks. Workshop on the Complex Networks, University of Bath,U.K. 2005. Conferencia Invitada.