Showing posts from 2011

"New" Paper: Facing Complexity: Prediction vs. Adaptation

One of the presuppositions of science since the times of Galileo, Newton, Laplace, and Descartes has been the predictability of the world. This idea has strongly influenced scientific and technological models. However, in recent decades, chaos and complexity have shown that not every phenomenon is predictable, even if it is deterministic. If a problem space is predictable, in theory we can find a solution via optimization. Nevertheless, if a problem space is not predictable, or it changes too fast, very probably optimization will offer obsolete solutions. This occurs often when the immediate solution affects the problem itself. An alternative is found in adaptation. An adaptive system will be able to find by itself new solutions for unforeseen situations. Gershenson, C. (In Press).  Facing Complexity: Prediction vs. Adaptation . To be published in Martorell, X. & Massip, A. (Eds.) Complexity and Language . Full paper at Versión en español en  ht

New Draft: Living in Living Cities

This paper presents and overview of current and potential applications of living technology to urban problems. Living technology can be described as technology that exhibits the core features of living systems. These features can be useful to solve dynamic problems. In particular, urban problems concerning mobility, logistics, telecommunications, governance, safety, sustainability, and society and culture are presented, while solutions involving living technology are reviewed. Finally, the usefulness of describing cities as living systems is discussed. Gershenson, C. (2011). Living in Living Cities. C3 Report 2011.09.

New Draft: Are Minds Computable?

This essay explores the limits of Turing machines concerning the modeling of minds and suggests alternatives to go beyond those limits. Gershenson, C. (2011). Are Minds Computable? C3 Tech. Report 2011.08.

The Laws of Information

1. Law of  Information Transformation . I nformation will potentially be transformed by interacting with other information. 2.  Law of Information Propagation .  Information propagates as fast as possible.  3.  Law of Requisite Complexity . M ore complex information will require more complex agents to perceive, act on, and propagate it. 4.  Law of Information Criticality .  Transforming and propagating information will tend to a critical balance be- tween its stability and its variability. 5.  Law of Information Organization .  Information produces constraints that regulate information production.  6.  Law of Information Self-organization .  Information tends to its preferred, most probable state.  7.  Law of Information Potentiality .  An agent can give different potential meanings to information.  8.  Law of Information Perception .  The meaning of information is unique for an agent perceiving it in unique, always changing open contexts. More at:

Video Talk: Self-Organization Leads to Supraoptimal Performance in Public Transportation Systems

UPDATE: Video also on youtube . You can find here the video (32 min) of a talk I gave at the last Lakeside Research Days in Klagenfurt, Austria. I speak about the results presented in this paper: Gershenson C (2011) Self-Organization Leads to Supraoptimal Performance in Public Transportation Systems. PLoS ONE 6 (6): e21469. The main idea is that self-organization can regulate public transportation systems in such a way that passengers wait less than the theoretical optimum. Of course, this means that the theory was wrong. Well, more precisely, theory made misguided assumptions. I thank Christian Bettstetter and Wifried Elmenreich for organizing the Research Days and Chrisitan Philipp for making the video. Tip: The video is high quality, so it takes some time to download, even if one chooses right click -> Switch to low quality. Cultivate patience...


Today was the last day of competitions for my first RoboCup . Already on its 15th year, one of its goals is to have by 2050 human-size robots playing against the soccer world champions and winning. I thought that was far fetched, but after seeing some robots in action, it doesn't seem that impossible anymore. There are several different leagues, playing in simulations, wheeled and humanoid robots of different sizes. The simulated leagues can have complex strategies and make nice moves. Wheeled robots can move very fast and are very good at kicking. Team Water from China defeated TechUnited Eindhoven from The Netherlands in the final in an exciting 6-5. Those bots play good! At the human-robot match, Water tied 5-5 against an allowing group of team leaders. Humans could have easily won if they wished, but it was more of a friendly game... The humanoid robots are a bit slower, but still there is action packed excitement in some matches. The Nao robots are a bit slow, but they ca

New Paper: Self-Organization Leads to Supraoptimal Performance in Public Transportation Systems

Gershenson C (2011) Self-Organization Leads to Supraoptimal Performance in Public Transportation Systems. PLoS ONE 6 (6): e21469. Abstract : The performance of public transportation systems affects a large part of the population. Current theory assumes that passengers are served optimally when vehicles arrive at stations with regular intervals. In this paper, it is shown that self-organization can improve the performance of public transportation systems beyond the theoretical optimum by responding adaptively to local conditions. This is possible because of a “slower-is-faster” effect, where passengers wait more time at stations but total travel times are reduced. The proposed self-organizing method uses “antipheromones” to regulate headways, which are inspired by the stigmergy (communication via environment) of some ant colonies.

Epidemiology and social networks

Excerpt : By definition, noncommunicable diseases cannot be transmitted. However, there is recent evidence of the op- posite, involving a change of scientific paradigm. We have a notion that cardiovascular diseases, cancer and diabetes are noncontagious. Actually, there are no physical mechanisms that help spread these diseases. Nevertheless, risk factors of several noncommunicable diseases—such as obesity, al- coholism and smoking—are spread across populations. Epidemiology and social networks , Carlos Gershenson,  Cir Cir  2011; 79 :199-200 Full Text : In English: [ pdf ] [ html ] En Español: [ pdf ] [ html ]

Postdoctoral Fellowships at UNAM

//Please forward to whom may be interested. The National Autonomous University of Mexico (UNAM) has an open call for postdoctoral fellowships. Candidates should have obtained a PhD degree within the last three years and be under 36 years, both to the date of the beginning of the fellowship. In previous years, there has been a 50% acceptance rate. Candidates are evaluated mainly by their number of papers published in ISI-indexed journals. The area of interests of candidates should fall within complex systems, artificial life, information, evolution, cognition, robotics, and/or philosophy. Interested candidates should send CV and a tentative project (1 paragraph) to Projects can be inspired from: Postdoctoral fellowships are between one and three years (renewing each year). Spanish is not a requisite. Accepted candidates would be working at the Computer Science Department of the IIMAS (

New draft: The Implications of Interactions for Science and Philosophy

Gershenson, C. (2011). The Implications of Interactions for Science and Philosophy . C3 Report 2011.04. Abstract : Reductionism has dominated science and philosophy for centuries. Complexity has recently shown that interactions---which reductionism neglects---are relevant for understanding phenomena. When interactions are considered, reductionism becomes limited in several aspects. In this paper, I argue that interactions imply non-reductionism, non-materialism, non-predictability, non-Platonism, and non-nihilism. As alternatives to each of these, holism, informism, adaptation, contextuality, and meaningfulness are put forward, respectively. A worldview that includes interactions not only describes better our world, but can help to solve many open scientific, philosophical, and social problems caused by implications of reductionism. Full text :

New draft: Polyethism in a colony of artificial ants

Marriott, Chris & Carlos Gershenson. Polyethism in a colony of artificial ants . C3 Report 2011.03. Abstract : We explore self-organizing strategies for role assignment in a foraging task carried out by a colony of artificial agents. Our strategies are inspired by various mechanisms of division of labor (polyethism) observed in eusocial insects like ants, termites, or bees. Specifically we instantiate models of caste polyethism and age or temporal polyethism to evaluate the benefits to foraging in a dynamic environment. Our experiment is directly related to the exploration/exploitation trade of in machine learning. Full text :

New draft: Self-organizing traffic lights at multiple-street intersections

Gershenson, C. & D. A. Rosenblueth (2011). Self-organizing traffic lights at multiple-street intersections . C3 Report 2011.02 Summary : Traffic light coordination is a complex problem. In this paper, we extend previous work on an abstract model of city traffic to allow for multiple street intersections. We test a self-organizing method in our model, showing that it is close to theoretical optima and superior to a traditional method of traffic light coordination.    Abstract : The elementary cellular automaton following rule 184 can mimic particles flowing in one direction at a constant speed. This automaton can therefore model highway traffic. In a recent paper, we have incorporated intersections regulated by traffic lights to this model using exclusively elementary cellular automata. In such a paper, however, we only explored a rectangular grid. We now extend our model to more complex scenarios employing an hexagonal grid. This extension shows first that our model can readily i

CfP: ECAL 2011

CALL FOR PAPERS: ECAL 2011   << Back to the origins of Alife >> ECAL 2011, European Conference on Artificial Life, an international conference on the simulation and synthesis of living systems 8-12 August 2011, Paris, France                         ===================== Artificial Life is an interdisciplinary undertaking that investigates the fundamental properties of living systems through the simulation and synthesis of biological entities and processes. It also attempts to design and build artificial systems that display properties of organisms, or societies of organisms, out of abiotic or virtual parts. ECAL, the European Conference on Artificial Life, is a biennial event that alternates with the US-based Alife conference series. --------------------- Welcome to ECAL 2011! Back then, in the early 1990's, the first two ECAL conferences in Paris and Brussels were mainly centered on theoretical biology and the physics of complex systems

IWSOS'2011 Proceedings Online

The Proceedings of IWSOS'2011 (starts tomorrow) are available in Google Books and in Springer . Self-Organizing Systems: 5th International Workshop, IWSOS 2011, Karlsruhe, Germany, February 23-24. 2011. Proceedings . Edited by Christian Bettstetter and Carlos Gershenson, LNCS 6557, Springer, 2011.

New Draft: Modular Random Boolean Networks

Poblanno-Balp, Rodrigo & Gershenson, Carlos (2011). Modular Random Boolean Networks.  C3 Report 2011.01. Abstract : Random Boolean networks (RBNs) have been a popular model of genetic regulatory networks for more than four decades. However, most RBN studies have been made with regular topologies, while real regulatory networks have been found to be modular. In this work, we extend classical RBNs to define modular RBNs. Statistical experiments and analytical results show that modularity has a strong effect on the properties of RBNs. In particular, modular RBNs are closer to criticality than regular RBNs. Full text :