The Geometry Junkyard

Wooden polyhedra

Mon, 25 Jan 2010 00:00:00 GMT

Wooden polyhedra from Japan (but with English explanations). And more, in Japanese.

Mathematical balloon twisting

Mon, 11 Jan 2010 00:00:00 GMT

Mathematical balloon twisting. Vi Hart makes polyhedra and polyhedral tangles from balloons.

Lun-Yi Tsai

Sat, 09 Jan 2010 00:00:00 GMT

Lun-Yi Tsai paints fine art of foliatied 3-manifolds, differentiable atlases, and other topological structures.

Packing Tetrahedrons, and Closing in on a Perfect Fit

Mon, 04 Jan 2010 00:00:00 GMT

Packing Tetrahedrons, and Closing in on a Perfect Fit. Elizabeth Chen and others use experiments on hundreds of D&D dice to smash previous records for packing density.

Contortion Engineering

Sun, 27 Dec 2009 00:00:00 GMT

Contortion Engineering. Some Escher-like impossible figures from Offworld Press.

Hyperbolic crochet coral reef

Mon, 14 Dec 2009 00:00:00 GMT

Hyperbolic crochet coral reef, the Institute for Figuring. Daina Taimina's technique for crocheting yarn into hyperbolic surfaces forms the basis for an exhibit of woolen undersea fauna and flora.

Mathematically correct breakfast

Mon, 07 Dec 2009 00:00:00 GMT

Mathematically correct breakfast. George Hart describes how to cut a single bagel into two linked Möbius strips. As a bonus, you get more surface area for your cream cheese than a standard sliced bagel.

Three

Sun, 04 Oct 2009 00:00:00 GMT

Three spiral tattoos from the Discover Magazine Science Tattoo Emporium.

Magazine Puzzle Fun

Wed, 30 Sep 2009 00:00:00 GMT

Magazine Puzzle Fun. Fifteen years of back issues of an Argentine magazine about pentominoes (in English).

30 computers

Wed, 09 Sep 2009 00:00:00 GMT

30 computers. Forrest McCluer makes polyhedral sculptures out of discarded electronics.

Platonic solids

Wed, 09 Sep 2009 00:00:00 GMT

Platonic solids transformed by Michael Hansmeyer using subdivision-surface algorithms into shapes resembling radiolarans. See also Boing Boing discussion.

Typeface Venus

Mon, 31 Aug 2009 00:00:00 GMT

Typeface Venus, Circle Marilyn, and Bubble Mona. village9991 uses quadtrees and superellipses to make abstract mosaics of famous faces.

Applications of shapes of constant width

Mon, 31 Aug 2009 00:00:00 GMT

Applications of shapes of constant width. A Reuleaux triangle doesn't quite drill out a square hole (it leaves rounded corners) but a different and less-symmetric constant-width shape based on an isosceles right triangle can be used to do so. This web page also discusses coin design, cams, and rotary engines, all based on curves of constant width; see also discussion on Metafilter.

Woolly thoughts

Sun, 30 Aug 2009 00:00:00 GMT

Woolly thoughts, mathematical knitwear.

Human Geometry

Sun, 30 Aug 2009 00:00:00 GMT

Human Geometry and Naked Geometry. The human form as a building block of larger geometric figures, by Mike Naylor.

Hyperbolic games

Thu, 07 May 2009 00:00:00 GMT

Hyperbolic games. Freeware multiplatform software for games such as Sudoku on hyperbolic surfaces, intended as a way for students to gain familiarity with hyperbolic geometry. By Jeff Weeks.

Eight foxes

Wed, 06 May 2009 00:00:00 GMT

Eight foxes. Daily geometry problems.

The HyperSphere, from an Artistic point of View

Thu, 12 Mar 2009 00:00:00 GMT

The HyperSphere, from an Artistic point of View, Rebecca Frankel.

Rectangular cartograms: the game

Tue, 17 Feb 2009 00:00:00 GMT

Rectangular cartograms: the game. Change the shape of rectangles (without changing their area) and group them into larger rectangular and L-shaped units to fit them into a given frame. Bettina Speckmann, TUE. Requires a browser with support for Java SE 6.

Sierpinski valentine

Thu, 12 Feb 2009 00:00:00 GMT

Sierpinski valentine from XKCD.

Fermat's spiral and the line between Yin and Yang

Tue, 10 Feb 2009 00:00:00 GMT

Fermat's spiral and the line between Yin and Yang. Taras Banakh, Oleg Verbitsky, and Yaroslav Vorobets argue that the ideal shape of the dividing line in a Yin-Yang symbol is formed, not from two semicircles, but from Fermat's spiral.

Flat equilateral tori.

Sat, 07 Feb 2009 00:00:00 GMT

Flat equilateral tori. Can one build a polyhedral torus in which all faces are equilateral triangles and all vertices have six incident edges? Probably not but this physical model comes close.

Voronoi diagrams at the Milwaukee Art Museum

Sat, 17 Jan 2009 00:00:00 GMT

Voronoi diagrams at the Milwaukee Art Museum. Scott Snibbe's artwork Boundary Functions, as blogged by Quomodumque.