Natural Computation and Self-Organization:
The Physics of Information Processing in Complex Systems
Winter 2008
Syllabus
Instructor: Prof. Jim Crutchfield (chaos@cse.ucdavis.edu; http://cse.ucdavis.edu/~chaos)
Assistant: Chris Ellison (cellison@cse.ucdavis.edu; http://cse.ucdavis.edu/~cellison)
Time: TuTh 2:10 - 3:30 PM
Location: 158 Roessler Hall
WWW: http://cse.ucdavis.edu/~chaos/courses/ncaso/
Contents
First Lecture (8 January): Overview
Readings (available via course website):
- Chaos, JP Crutchfield, JD Farmer, NH Packard, RS Shaw, Scientific American 255 (1986)
46–57.
- Odds, Stanislaw Lem, New Yorker 54 (1978) 38–54.
Topics:
- Introduction and motivations
- Four parts: Self-Organization, Measurement Theory, Information Processing, Natural
Computation
- Survey interests, background, and abilities
- Course logistics
- Exams and projects
- Software and program development
1 Self-Organization
Reading: Nonlinear Dynamics and Chaos, Strogatz (NDAC), and Course Lecture Notes
Theme: Forms of Randomness, Order, and Intrinsic Instability
- Nonlinear Dynamics:
- Qualitative dynamics
- ODEs and maps
- Bifurcations
- Stability, instability, and chaos
- Quantifying (in)stability
- Pattern-forming systems:
- Instability and stabilization of patterns
- Cellular automata, map lattices, spin systems
1.1 Lecture 2 (10 January): The Big Picture
Reading: NDAC, Chapters 1 and 2.
Topics:
- Pendulum demo
- Discuss Chaos and Odds readings and homework
- Qualitative dynamics: A geometric view of behavior
- State space
- Flows
- Attractors
- Basins
- Submanifolds
- Concrete, but simple example: One-dimensional flows
Homework: Everyday unpredictability; see handout or website. Due in one week, but be prepared to
discuss at next meeting.
1.2 Lecture 3 (15 January): Example Dynamical Systems
Reading: NDAC, Sections 6.0-6.7, 7.0-7.3, and 9.0-9.4.
Topics:
- Continuous-time ODEs
- 2D flows: Fixed points (Sec. 6.0-6.4)
- 2D flows: Limit cycles (Sec. 7.0-7.3)
- 3D flows: Chaos in Lorenz (Sec. 9.0-9.4)
- Simulation demo
- From continuous to discrete time (Sec. 9.4)
- Poincaré maps and sections
- Lorenz ODE to cusp map
- Rössler ODE to logistic map (pp. 376–379)
- Discrete-time maps
1.3 Lecture 4 (17 January): The Big, Big Picture (Bifurcations)
Reading: NDAC, Chapters 3 and 8 and Sec. 10.0-10.4.
Topics:
- Qualitative dynamics: Space of all dynamical systems
- Example: Bifurcations of one-dimensional flows
- Saddle node
- Transcritical
- Pitchfork
- Catastrophe theory
- Catastrophes: Fixed point to fixed point bifurcation
- Example: Cusp Catastrophe
- Catastrophe theory classification of fixed point bifurcations
- Bifurcations in discrete-time maps: Logistic map
- Fixed point to limit cycle
- Phenomenon and calculation
- Limit cycle to limit cycle
- Phenomenon and calculation
- Routes to chaos: Period-doubling cascade
- Phenomenon and calculation
- Band-merging
- Periodic windows and intermittency
- Simulation demo
Homework: Collect Week 0’s, assign this week’s today.
1.4 Lecture 6 (22 January): Mechanism of Chaos: Stable Instability
Reading: NDAC, Sec. 12.0-12.3, 9.3, and 10.5.
Topics:
- Chaotic mechanisms: Stretch and fold
- Baker’s map
- Cat map (and stretch demo)
- Henon map: stretch-fold and self-similarity
- Roessler attractor branched manifold
- Dot spreading: Roessler and Lorenz ODEs
- Lyapunov characteristic exponents (LCEs)
- Time to unpredictability
- Dissipation rate
- Attractor LCE classification
- Chaos defined
1.5 Lecture 7 (24 January): Example Chaotic Maps (that you can analyze)
Reading: NDAC, Chapter 10.
Topics:
- Shift map
- LCEs for maps
- Tent map
- Logistic map
- LCE view of period-doubling route to chaos
- Period-doubling self-similarity
- Renormalization group analysis of scaling
Homework: Collect Week 1’s, assign this week’s today.
2 From Determinism to Stochasticity
Reading: Lecture Notes.
Theme: Stochasticity and Measurement
- Probability theory of Dynamical Systems
- Stochastic Processes
- Measurement Theory
2.1 Lecture 8 (29 January): Probability Theory of Dynamical Systems
Reading: Lecture Notes.
Topics:
- Probability theory review
- Dynamical evolution of distributions
- Invariant measures
- Examples
2.2 Lecture 9 (31 January): Stochastic Processes
Reading: Lecture Notes.
Topics:
- Review last lecture.
- Processes
- Markov chains
- Statistical equilibrium
- Hidden Markov models
- Examples: Fair coin, periodic, golden mean, even, and others
Homework: Collect Week 2’s, assign this week’s today.
2.3 Lecture 10 (5 February): Measurement Theory
Reading: Lecture Notes.
Topics:
- Review last lecture.
- State-space partitioning
- Orbit and sequence spaces
- Markov partitions
- Generating partitions
- Examples: 1D maps (Optional: 2D Cat map)
3 Information Processing
Reading: Elements of Information Theory, Cover and Thomas (EIT), and Computational Mechanics
Reader, JPC (CMR)
Theme: Information, Uncertainty, and Memory
- Entropies
- Communication Channel (and coding theorems)
- Mutual Information and Information metric
- Excess Entropy
- Transient Information
- Connection to Dynamics: Entropy rate and LCEs
3.1 Lecture 11 (7 February): Entropies
Reading: EIT, Chapters 1 and 2.
Topics:
- Motivation: Information
Energy
- Information as uncertainty and surprise
- Information sources: Ignorance of forces or initial conditions, deterministic chaos, and ...?
- Axioms for a measure of information
- Entropy function
- Convexity
- Joint and Conditional Entropy
- Mutual information
- Examples
Homework: Collect Week 3’s, assign Week 4’s today.
3.2 Lecture 12 (12 February): Information in Processes
Reading: EIT, Sec. 5-5.4 and 8-8.5 and Chapter 4.
Topics:
- Communication channels
- Coding theorems
- Entropy rates for Markov chains
- Entropies for times series
- Entropy convergence
3.3 Lecture 13 (14 February): Memory in Processes
Reading: CMR article RURO.
Topics:
- Excess entropy
- Examples
- Transient information
- Examples
Homework: Collect Week 4’s, assign Week 5’s today.
4 Natural Computation
Reading: Computational Mechanics Reader, JPC (CMR)
Theme: Causal Architecture of Dynamical Systems and Stochastic Quantum and Processes
- Prediction and Learning
- ε-Machines and Causal Architecture
- Measures of Structural Complexity
- How to Calculate
- Complex Materials
- Quantum Systems
4.1 Lecture 14 (19 February): The Learning Channel
Reading:
- CMR article RURO (Intro) and Lecture Notes.
- CMR article Chance and Order, Stanislaw Lem, New Yorker 59 (1984) 88–98.
- CMR article Revealing Order in the Chaos, Mark Buchanan, New Scientist, 26 February 2005;
available at cse.ucdavis.edu/~chaos/news/.
Topics:
- The Learning Channel
- The Prediction Game
- Space of histories
- Predictive equivalence relation
- Causal states
- ε-Machines
Projects: Project topic should be selected by now.
4.2 Lecture 15 (21 February): ε-Machines
Reading: CMR article CMPPSS.
Topics:
- Examples: Predictable, fair coin, period-two
- Optimal Prediction
- Minimality
- Uniqueness
- Minimal Sufficient Statistic
- Minimal Stochasticity
Homework: Collect Week 5’s, assign this week’s today.
4.3 Lecture 16 (26 February): Measures of Structural Complexity
Reading: CMR article CMPPSS.
Topics:
- Entropy rate
- Statistical complexity
- Excess entropy bound
- Examples: (hidden) Markov chains and dynamical systems
Material Covered: NDAC readings, EIT readings, and CMR article RURO.
Topics Covered:
- Dynamics
- Information Theory
4.4 Lecture 17 (28 February and 4 March): Complex Materials or ?
I am currently considering replacing the remaining lectures with new material on causal
inference, rate distortion theory, and interactive learning.
Reading: CMR articles BTFM1 and BTFM2.
Topics:
- One-Dimensional materials: Physics of polytypes
- Experimental studies
- Fault model
- ε-Machine spectral reconstruction
- Structure in disorder: Beyond the fault model
- Zinc-Sulfide
Homework: Week 6’s due; assign Week 7’s.
4.5 Lecture 18 (6, 11, and 13 March): Computation in Quantum Systems or ?
Reading: CMR article CIFQP.
Topics:
- Stochastic languages and machines
- Quantum languages
- Quantum machines
- Examples: Quantum fair coin, golden mean, even processes
- Quantum dynamical systems: Iterated beam splitter and ion traps
- Quantum computation
Homework: Week 7’s due 6 March.
5 Project Presentations
- Presentations will be organized according to class size.
- If the class is large, most likely they will be given at a mini-workshop, some evening.
Note: Project write-ups due Friday 14 March.