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Complexity Digest wrote a new blog post titled Winter School on Complexity Science
The 2018 Winter School provides an overview of complexity and complex systems science that empowers participants search for their own answers to these questions. The knowledge gained will enable participants to apply complexity science ideas in their own domains. Essentially the school will: teach basic aspects of complexity and complex systems, answering the question: What makes a system complex? Aspects that will be covered include nonlinearity, order disorder & chaos, emergence and complex adaptive systemsintroduce methods, models and simulation tools to study the behaviours of complex...
7 hours ago
Complexity Digest wrote a new blog post titled Re-conceptualizing the origins of life
Over the last several hundred years of scientific progress, we have arrived at a deep understanding of the non-living world. We have not yet achieved an analogous, deep understanding of the living world. The origins of life is our best chance at discovering scientific laws governing life, because it marks the point of departure from the predictable physical and chemical world to the novel, history-dependent living world. This theme issue aims to explore ways to build a deeper understanding of the nature of biology, by modelling the origins of life on a sufficiently abstract level, starting...
Complexity Digest wrote a new blog post titled Building Codes for Bacterial Cities | Quanta Magazine
Biofilms are bacterial fortresses, but understanding how hydrodynamics and competition shape their architecture could reveal their subtle weaknesses. Source:
2 days ago
Complexity Digest wrote a new blog post titled The Beautiful Intelligence of Bacteria and Other Microbes
Bacterial biofilms and slime molds are more than crude patches of goo. Detailed time-lapse microscopy reveals how they sense and explore their surroundings, Source:
3 days ago
Complexity Digest wrote a new blog post titled A Plea for not Watering Down the Unseemly: Reconsidering Francisco Varela’s Contribution to Science
Context: In the past three decades, the work of Varela has had an enormous impact on current developments in contemporary science. Problem: Varela’s thought was extremely complex and multifaceted, and while some aspects – notably his contributions to the autopoietic theory of living and enactivist approach to cognition – have gained widespread acclaim, others have been ignored or watered down. Method: We identify three dimensions of Varela’s thought: (i) anti-realism of the “middle way”; (ii) anti-foundationalism of the circular/recursive...
5 days ago
Complexity Digest wrote a new blog post titled Mathematical Work of Francisco Varela
Purpose: This target article explicates mathematical themes in the work of Varela that remain of current interest in present-day second-order cybernetics. Problem: Varela’s approach extended biological autonomy to mathematical models of autonomy using reflexivity, category theory and eigenform. I will show specific ways that this mathematical modeling can contribute further to both biology and cybernetics. Method: The method of this article is to use elementary mathematics based in distinctions (and some excursions into category theory and other constructions that are...
5 days ago
Complexity Digest wrote a new blog post titled Enacting Enaction: A Dialectic Between Knowing and Being
Context: The notion of “enaction,” as originally expounded by Varela and his colleagues, was introduced into cognitive science as part of a broad philosophical framework combining science, phenomenology, and Buddhist philosophy. Its intention was to help the researchers in the field avoid falling prey to various dichotomies (mind/body, self/world, self/other) bedeviling modern philosophy and science, and serve as a “conceptual evocation” of “non-duality” or “groundlessness: an ongoing and irreducible circulation between the flux of lived...
5 days ago
Complexity Digest wrote a new blog post titled XLVII Winter Meeting on Statistical Physics 2018
The purpose of the meeting is to bring together the national community of physicists working on statistical physics and related areas, in order to exchange knowledge, results and discuss new lines of research.  We also invite a group of internationally-well known scientists who have made fundamental contributions in their respective fields. This provides the opportunity to exchange ideas between national and foreign colleagues in a pleasant, inclusive and informal environment. The main program consists of plenary lectures given by...
6 days ago
Complexity Digest wrote a new blog post titled Social Systems Programming I: neural and behavioral control mechanisms
Social systems can be defined as autopoietic networks of distinctions and rules that specify which actions should be performed under which conditions. Social systems have an enormous power over human individuals, as they can “program” them to sacrifice resources, happiness, loved ones and even themselves to the perpetuation of the system—as exemplified by religious celibacy, honor killings and suicide bombings. Such overriding of the biological instincts of survival and procreation demands powerful control mechanisms. The present paper surveys some of the basic neural and...
6 days ago
Complexity Digest wrote a new blog post titled Constraints on physical reality arising from a formalization of knowledge
There are (at least) four ways that an agent can acquire information concerning the state of the universe: via observation, control, prediction, or via retrodiction, i.e., memory. Each of these four ways of acquiring information seems to rely on a different kind of physical device (resp., an observation device, a control device, etc.). However it turns out that certain mathematical structure is common to those four types of device. Any device that possesses a certain subset of that structure is known as an “inference device” (ID). Here I review some of the properties of IDs,...
7 days ago
Complexity Digest wrote a new blog post titled Dissipative structures and irreversibility in nature: Celebrating 100th birth anniversary of Ilya Prigogine (1917–2003)
Friends and colleagues who knew Ilya Prigogine well called him “A poet of thermodynamics.” It is an apt description. When Prigogine talked about thermodynamics and irreversible processes, one had the sense he understood or knew more than what his words conveyed. Natural processes all around us are irreversible; it is a fact. Their consequence is not merely to increase the entropy of the universe and destroy order. They can also do the opposite: create highly ordered complex structures with extraordinary properties and create life itself. Prigogine saw this as a profound aspect of...
8 days ago
Complexity Digest wrote a new blog post titled The Unforgiving Math That Stops Epidemics
As the annual flu season approaches, medical professionals are again encouraging people to get flu shots. Perhaps you are among those who rationalize skipping the shot on the grounds that “I never get the flu” or “if I get sick, I get sick” or “I’m healthy, so I’ll get over it.” What you might not realize is that these vaccination campaigns for flu and other diseases are about much more than your health. They’re about achieving a collective resistance to disease that goes beyond individual well-being — and that is governed by...
9 days ago
Complexity Digest wrote a new blog post titled Characterizing the structural diversity of complex networks across domains
The structure of complex networks has been of interest in many scientific and engineering disciplines over the decades. A number of studies in the field have been focused on finding the common properties among different kinds of networks such as heavy-tail degree distribution, small-worldness and modular structure and they have tried to establish a theory of structural universality in complex networks. However, there is no comprehensive study of network structure across a diverse set of domains in order to explain the structural diversity we observe in the real-world networks. In this paper,...
9 days ago
Complexity Digest wrote a new blog post titled Phase Coexistence in Insect Swarms
Animal aggregations are visually striking, and as such are popular examples of collective behavior in the natural world. Quantitatively demonstrating the collective nature of such groups, however, remains surprisingly difficult. Inspired by thermodynamics, we applied topological data analysis to laboratory insect swarms and found evidence for emergent, material-like states. We show that the swarms consist of a core “condensed” phase surrounded by a dilute “vapor” phase. These two phases coexist in equilibrium, and maintain their distinct macroscopic properties even...
10 days ago
Complexity Digest wrote a new blog post titled Large-scale study of social network structure and team performance in a multiplayer online game
A question of interest in both theory and practice is if and how familiarity between members of a team, expressed in terms of social network structure, relates to the success of the team in a given task. In this paper we revisit this important question in a novel manner by employing game outcome statistics from Dota 2, a popular team-based multiplayer online game, combined with network data from Steam Community, a social networking service for gamers. We conduct a large-scale analysis of 4168 teams to study how network density, and the minimum and maximum degree of the within-team social...
10 days ago
Complexity Digest wrote a new blog post titled Measuring Influence in Science: Standing on the Shoulders of Which Giants?
I study the measurement of the influence of scientists based on bibliographic data. I propose a new measure that accounts for indirect influence and allows to compare scientists across different fields of science. By contrast, common measures of influence that “count citations”, such as the h-index, are unable to satisfy either of these two properties. I use the axiomatic method in two opposite ways: to highlight the two limitations of citation-counting schemes and their independence, and to carefully justify the assumptions made in the construction of the proposed measure.  ...
10 days ago
Complexity Digest wrote a new blog post titled Breaking the spell of nestedness
Mutualistic interactions, which are beneficial for both interacting species, are recurrently present in ecosystems. Observations of natural systems showed that, if we draw mutualistic relationships as binary links between species, the resulting bipartite network of interactions displays a widespread particular ordering called nestedness. On the other hand, theoretical works have shown that a nested structure has a positive impact on a number of relevant features ranging from species coexistence to a higher structural stability of communities and biodiversity. However, how nestedness emerges...
10 days ago
Complexity Digest wrote a new blog post titled Self-referential basis of undecidable dynamics: from The Liar Paradox and The Halting Problem to The Edge of Chaos
In this paper we explore several fundamental relations between formal systems, algorithms, and dynamical systems, focussing on the roles of undecidability, universality, diagonalization, and self-reference in each of these computational frameworks. Some of these interconnections are well-known, while some are clarified in this study as a result of a fine-grained comparison between recursive formal systems, Turing machines, and Cellular Automata (CAs). In particular, we elaborate on the diagonalization argument applied to distributed computation carried out by CAs, illustrating the key...
11 days ago
Complexity Digest wrote a new blog post titled Network Theory Faculty position at UC Davis
The University of California, Davis invites applications for a faculty position in network theory, which is an interdisciplinary academic field using graph theory, statistical mechanics, and applied mathematics to elucidate the mathematical foundations underlying the organization and function of networks across a wide range of applied disciplines. The appointment will be at the Assistant or Associate Professor level, with opportunity for a more senior level appointment for an exceptional candidate, with an intended start date of Fall 2018. The appointment will reside in the Department of...
12 days ago
Complexity Digest wrote a new blog post titled True AI is both logically possible and utterly implausible
Machines seem to be getting smarter and smarter and much better at human jobs, yet true AI is utterly implausible. Why? Source:
14 days ago