Ethnomathematics: Mathematics and Culture

Video Lectures

Displaying all 13 video lectures.
Lecture 1
Geometric Designs & Symmetries
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Geometric Designs & Symmetries
Geometric designs and the four basic symmetry types: Rotations, Reflections, Translations, and Glide-Reflections.
Cultural Example: Egyptian art has no glide-reflections.
Lecture 2
Central Symmetry Groups
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Central Symmetry Groups
Central Symmetry Goups (Cn and Dn), the "products" of two symmetries, and Da Vinci's Theorem about these groups. Cultural example on Southwest American Indians and 4-fold rotations.
Lecture 3
Strip Symmetries
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Strip Symmetries
7-strip symmetry groups, with the beginnings of why the "other 5" cannot exist.
Cultural Examples: Tibetan Sand Mandalas vs. Norwegian Rosemaling.
Lecture 4
Wallpaper Symmetry
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Wallpaper Symmetry
Wallpaper (all-over) symmetry groups, and classifying the 17 types of symmetry groups.
Cultural Example: Symmetry preferences of Hmong sub-groups.
Lecture 5
Color Symmetries
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Color Symmetries
This lecture will cover color symmetry patterns.
Lecture 6
Symmetry Combinations
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Symmetry Combinations
Using the calculations of combinations of symmetries to classify the possible perfect 2-colorings in strip patterns. Applying the same ideas to designs with two "similar", but not identical, motifs. Cultural example: U.S. Depression glass.
Lecture 7
Symmetry Breaking
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Symmetry Breaking
When a culture uses some technique to deliberately break the symmetry of a design, and when they do so on a geometrically regular basis, we would like to be able to model what it is that they are doing.
Lecture 8
Double Strips & Compound Patterns
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Double Strips & Compound Patterns
Designs created by combining copies (Double Strips) or interlacing pairs of patterns (Compound Patterns). Understanding orbits of motifs in a design.
Lecture 9
Introduction to Puzzles and Games
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Introduction to Puzzles and Games
Logic puzzles, or Combinatorial puzzles, and their analysis. The use of Game Trees to solve such puzzles. Examples include "Three Mug" problems (15th century Europe), and Tchuka Ruma (Indonesia/Malaysia), a solitaire form of Mancala.
Lecture 10
Game Trees and Game Charts
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Game Trees and Game Charts
Creating Game Trees and Game Charts to analyze puzzles and games, and using lookahead to simplify such trees and charts. Examples include "River Crossing" problems (9th century Europe), Tic-Tac-Toe, and "Blockade" games from many countries. Pong Hau K'i as a Maximal Blockade game.
Lecture 11
Game Charts & Blockade Games
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Game Charts & Blockade Games
Using Game Charts to analyze maximal blockade games. Using lookahead to simplify such analysis. Examples include Pong Hau K'i (from China) and equivalent games from Korea, India, and Thailand; Berry Patch Scramble from General Mills, and Mu Torere from the Maori (New Zealand). Introducing Achi, from Ghana.
Lecture 12
Win Trees for Games. Achi, Mancala
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Win Trees for Games. Achi, Mancala
Using game trees from specific positions, e.g. 1- or 2-ply trees, to analyze a position. Using longer game trees from a position to demonstrate it's a winning position. Examples with Achi (from Ghana) and a version of Mancala also from Ghana.
Lecture 13
Number Symbols
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Number Symbols
The symbols various cultures have used to write, or transcribe, numbers.