# Awesome Complexity

A curated list of resources related to complex systems, the scientific field studying systems with multiple interacting parts and emergent properties.

## Contents

- Concepts
- Scientific Journals
- Blogs/Journals
- Societies/Communities
- Organizations
- Models
- Software
  - Freely to use or open source
  - Proprietary
- Other Resources
- Books

## Concepts

- Attractor - A trajectory in the state space of a system in which it tends to evolve towards.
- Autopoiesis - The ability of a system to create and maintain itself.
- Chaos - Theory of chaotic systems.
- Complexity - The subject of complex systems science.
- Developmental Systems Theory - Theoretical perspective on biological development, heredity, and evolution.
- Dissipative System - A thermodynamically open system far from thermodynamic equilibrium.
- Distributed Control - A control system without a central supervisor.
- Edge of Chaos - The transition zone between order and disorder.
- Emergence - The whole is greater than the sum of the parts.
- Fractal - Self-similar structure.
- Hysteresis - Dependence of the state of a system on its history.
- Holon - System that is both a whole and a part.
- Network/Graph - Network with non-trivial topological features.
- Phase Transition - Transition between states of matter.
- Robustness - Ability to tolerate perturbations.
- Self-Organization - The process where form arises from local interactions between parts of an initially disordered system.
- Simulation - Imitation of the operation of a real-world process or system.

## Scientific Journals

- Complexity - Cross-disciplinary journal about complex adaptive systems (open access).

## Blogs/Journals

- The Systems Thinker - Articles with a systems perspective on various topics.
- Complexity Digest - News feed on complexity.
- Fractal forums - Forum and discussion community about fractals.

## Societies/Communities

- Complex Systems Society - Scientific society for the study of complex systems.
- Complexity research - Informal slack community for keeping up to date with new findings in complex systems research.
- Complexity Adventures - Complexity community of practice (formerly known as Complexity Weekend).

## Organizations

- New England Complex Systems Institute (NECSI) - Independent academic research and educational institution.
- The Vermont Complex Systems Center - Research and educational center (University of Vermont).
- Santa Fe Institute - Independent research and education center.
- Institut rhônalpin des systèmes complexes - IXXI - Research center (ENS Lyon).
- Waterloo Institute for Complexity & Innovation (WICI) - Research center (University of Waterloo).
- Institut des Systèmes Complexes - Paris Ile-de-France (ISC-PIF) - An inter-institutional organization (CNRS unit) on complex systems research.

## Models

- Boids - Emergent flocking behavior.
  - Craig Reynolds’ Boids page - The creator’s webpage with lots of links to multiple implementations.
- Cellular automata - Discrete compuation model.
- Elementary cellular automaton - One-dimensional cellular automata.
- Game of Life - Two-dimensional cellular automaton with emergent life-like patterns.
  - ConwayLife - Community for game-of-life and similar simulations.
  - golly - State-of-the-art simulator.
  - Lenia - Continuous generalization of the game of life.
- Double pendulum - Chaotic motion.
- Kuramoto model - Synchronization.
- Barabási–Albert (BA) model - Algorithm for generating random graphs with preferential attachment.
- Schelling’s model - Agent-based model for segregation.
- Ising model - Simple model that can show phase transitions.
- Reaction-diffusion - Self-organization and pattern formation model.
- Abelian sandpile model - Model showing self-organized criticality.

## Software

### Freely to use or open source

- NetLogo - Multi-agent modeling environment based on the LOGO language. It comes with a very large library of toy models.
- Simulus - ABM library in Python.
- Swarm - A platform for agent-based models written in Objective-C, models are coded in Java or Objective-C.
- Repast - Agent-based modeling and simulation platforms, models coded in C++ and Java.
- MASON - Multiagent simulation library core in Java.
- HASH - Graph and agent simulation platform.
- Hybrid Automata Library - Java library for hybrid modeling combining agent-based and partial-differential equation components.

### Proprietary

- Stella - Modelling and interactive simulations.
- Ventity/Vensim - Simulation software.
- Cosmo Tech platform - Digital twins simulator software.

## Other Resources

- Complexity Explorer - Educational site with news/blog.
- Map of Complex systems History - An impressive overview of the evolution of complex systems thinking.
- Stanford Complexity Group - YouTube channel with videos from the group’s events.
- Awesome Network Analysis - Resources for analysis of network data.
- Complexity Explained - Interactive educational website.

## Books

- Wiener, N. (2016). Cybernetics or control and communication in the animal and the machine. - The book introduced the term cybernetics to describe a self-regulation mechanism.
- Scheffer, M. (2009). Critical transitions in nature and society. Princeton, N.J: Princeton University Press. - A nicely written and accessible description of the critical transition and related concepts.
- Nicolis, G., Basios, V., & (Firm), W. S. (2015). Chaos, information processing and paradoxical games: the legacy of John S. Nicolis. Singapore; Hackensack, N.J.: World Scientific Pub. Co. - An edited volume of studies honoring the legacy of John Nicolis contribution to complex systems.
- Newman, M. E. J. (2010). Networks: an introduction. Oxford; New York: Oxford University Press. - A comprehensive introduction to network science.
- Mitchell, S. D. (2013). Unsimple truths: science, complexity, and policy. Chicago: Univ. of Chicago Press. - The book introduces the perspective of integrative puralism as a way of understanding and studying the world.
- Maturana, H. R., & Varela, F. J. (2008). The tree of knowledge: the biological roots of human understanding. Boston: Shambhala. - The book is an exposition of the non-representational vew of knowledge.
- Mandelbrot, B. (2006). The fractal geometry of nature. New York: W.H. Freeman and Company. - Beautiful introduction to the world of fractals.
- Kauffman, S. (2014). At Home in the Universe The Search for the Laws of Self-Organization and Complexity. Cary: Oxford University Press, USA. - The book introduces in an accessible way the influence of concepts such as self-organization and the edge of chaos.
- Gros, C. (2015). Complex and adaptive dynamical systems: a primer. Cham: Springer. - Technical and accessible introduction to a number of important concepts in complex systems science.
- Downey, A. (2012). Think complexity. Needham, Massachusetts: Green Tea Press. - A hands-on approach exploring complex systems models with Python.
- Boccara, N. (2014). Modeling complex systems. Springer-Verlag New York. - An overview of important mathematical models of complex systems.
- Barrat, A., Barthelemy, M., & Vespignani, A. (2013). Dynamical processes on complex networks. Cambridge: Cambridge University Press - Dynamic models on complex networks.

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