1. Prof. Marie desJardins, January 28, 2016
HONR 300/CMSC 491 Complexity
Prof. Marie desJardins, January 28, 2016
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2. Course Topics
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3. Reproduced from Gary Flake, The Computational Beauty of Nature, MIT Press, 1998
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4. Topics 1/26-2/9: 2/11-2/25: 3/1-3/10: 3/22: 3/24-3/29: 3/31-4/17:
4/12-4/19:
4/21-4/28:
5/3-5/??:
Complexity, mathematical and algorithmic background
Fractals
Chaos
Midterm
Cellular and finite-state automata (machines)
Multi-agent systems
NetLogo project presentations
Optimization and adaptation
Presentations, additional topics if time
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5. Sources of Complexity
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6. Complexity and Agents
Complexity in systems arises from interactions between individual components or agents of the system
Emergence is the concept that system behavior is not readily inferred from individual agent behaviors: it arises from the interactions between the agents in complex and beautiful ways
Self-similarity arises when similar patterns occur at multiple levels of abstraction or multiple parts of a system
Sources of complexity:
Parallelism
Recursion
Adaptation
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7. Parallelism michaelmcfadyenscuba.info/ reference.findtarget.com
mathaware.org
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8. Parallelism
Parallelism: Many copies of identical or highly similar agents operating simultaneously (but potentially interacting with each other)
Examples:
Biological/biochemical systems: Fish schools, ant colonies, protein folding
Mathematical models: Cellular automata
Physical processes: Galaxy formation, planetary rings
Social/technological systems: Economic markets, social networks, structure of the Internet, RAID disk arrays
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9. Recursion faqs.org wikipedia.org condostx.com wallpaperstock.net
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10. Recursion
Recursion: a repetitive process in which a process is invoked repeatedly on successively smaller versions of the entity or problem being manipulated
Examples of recursion:
Biological processes: Tree branches, seashells, coral reefs
Mathematical models: Fractals, L-systems
Physical processes: Coastal formation, sand dunes, snowflakes, cloud formations, mountain ranges
Social systems: Micromarkets, hierarchical organizations, clan systems, governmental systems, knowledge structures
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11. Adaptation intranet.friaryschool.net pinnycohen.com mms.nps.gov
scienceray.com
childrenshospital.org
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12. Adaptation
Adaptation: Modification of an agent or a species (collection of agents over time, through reproduction) in response to environmental pressures (competition for resources)
Examples:
Biological systems: Evolution, drug-resistant bacteria, learning and memory, cancer
Mathematical models: Dynamic optimization, feedback models
Physical processes: Global climate change, meandering river shapes, mineral formation
Social systems: Opinion formation, market fads, competitive markets, social protocols/etiquette
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13. What Does Complexity Mean to You?
What did you think you were signing up for when you registered for this class?
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14. How Big is a Complex System?
Powers of Ten movie (9 min):
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15. What Next?
Reminders:
The first reading journal is due 12 hours before our next class (i.e., by 8:30 p.m. on Monday, February 1).
The “Complexity in Everyday Life” assignment is due next Thursday, February 4.
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