Fractals/IFS, dimension, coding/symbolic dynamics
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what happened before the 1st photo: TBA;
general idea: chaotic systems (e.g., the Lorenz attractor), how to
understand/describe them
for example, the middle-third Cantor set, denoted for now \(C\), its
"remarkable" properties:
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non-empty, compact (i.e., closed and bounded)
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perfect (each point in \(C\) is limit of other points in
\(C\)); Thm: a perfect set is uncountable.
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it is nowhere dense: its closure, here \(C\) itself, contains no
intervals
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has measure (here "length") zero
\(C\) can be obtained by an IFS, see next photo.
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photo 1 Iterated Function Systems (IFS)
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photo 2 Box-counting dimension
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photo 3 Box-counting dimension continued
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photo 4 Coding, the doubling map
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photo 5 Coding continued
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photo 6 The \(\beta\)-transformation
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photo 7 Extension of the
\(\beta\)-transformation, the logistic family
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next time: bifurcations
Can look at these links, or search wikipedia
https://en.wikipedia.org/wiki/Minkowski%E2%80%93Bouligand_dimension
a.k.a. Box-dimension
https://en.wikipedia.org/wiki/Hausdorff_dimension
http://math.arizona.edu/~shankar/efa/efa2.pdf
https://www.amazon.com/Fractals-Everywhere-Michael-F-Barnsley/dp/0120790610#reader_0120790610
http://wwwf.imperial.ac.uk/~jswlamb/M345PA46/%5BB%5D%20chap%20IX.pdf
Barnsley CH 10: measures on fractals
http://www.davidmartipete.cat/outreach/140122-FractalsPresentation.pdf
https://en.wikipedia.org/wiki/Iterated_function_system
https://en.wikipedia.org/wiki/Hausdorff_distance
https://en.wikipedia.org/wiki/Collage_theorem
the logistic family
period doubling in the logistic family, how it leads to chaos
the universality of this phenomenon, discovered and explained by M. Feigenbaum
https://en.wikipedia.org/wiki/Mitchell_Feigenbaum#Work