fuchsbau

Complexity: The Emerging Science at the Edge of Order and Chaos, Mitchell Waldrop

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• Substrat: complex adaptive systems govern our lives
  • life is path-dependent & locked-in in unpredictable outcomes (examples: QWERTY or VHS, which was judged technically inferor to Beta)
• complex adaptive system (dynamic, self-organising, self-reinforcing, emergent, adaptive, coevolutionary behaviour):
  • 1) independent agents interact with each other;
  • 2) many levels of organisation;
  • 3) anticipate the future;
  • 4) have many niches (which create new niches; equilibrium is never achieved)
  • complex adaptive systems have incessant urge to organize themselves into patterns
• emergence: building blocks at one level combining into new building blocks at a higher level
• autocatalytic set: compounds form self-reinforcing web of reactions (phase transition) that catalyses creation of more compounds
• exploitation learning: strengthen existing connections; improve what you already have
• exploration learning: rewire nodes; take the risk of screwing up big in return for the chance of winning big
• Life: Too static --> "Life/Intelligence" --> Too noisy
  • selection can get a complex adaptive system to the edge of chaos
• initial cooperation + tit for tat is dominating strategy in simulated negotiation game
• necessary for game-playing agents to prosper: prediction and feedback
• far from equilibrium the "gravitational pull" of rational expectations becomes weak
• Santa Fe's intellectual agenda: understand intertwining processes of emergence and adaptation (i.e. research complex adaptive systems)
  • George Cowan founded the Santa Fe institute in a collaborative manner: he guided a decentralised, emergent decision-making process among highly capable individuals; he focused on getting consensus on the institute's direction first. Later they tried to avoid hype and inflated expectations.
• boids create flocking behaviour with 3 rules for individuals:
  • 1) maintain minimum distance from other objects; 2) match velocities with boids in neighborhood; 3) move toward perceived centre of mass of boids in neighborhood
• noteworthy:
  • "Any given organism’s ability to survive and reproduce depends on what niche it is filling"
  • "Evolution doesn’t care whether problems are well defined or not. Adaptive agents are just responding to a reward."; "What you’re trying to do is maximize robustness, or survivability, in the face of an ill-defined future."
  • "(...) living systems always seem to emerge from the bottom up, from a population of much simpler systems."; "top-down systems are forever running into combinations of events they don’t know how to handle"
  • "(...) fitness isn’t decreed from the outside at all. It arises from the dance of coevolution"
  • "There are models where the species that dominate in the stable period after the upheaval may be less fit than the species that dominated beforehand."
  • "(...) the institute might actually be much better off without a permanent faculty. So why not just keep the institute going in its catalyst role?"