thursday, february 03, 2011
Observational math
I like learning geometry and topology terms that make you notice and describe patterns out in the wild:
Catenary
The wires hanging between those pylons form catenary curves, which describe what happens when you hang an ideal string between two points. The word is also used for catenary wires (which power trains).
Caustic
These shiny light shapes are caustics generated by a spotlight shining on a curved piece of plastic (Untitled, 1967, Giovanni Anselmo, Museum of Modern Art). You can see a typical caustic by taking a mug of tea into the sunlight and looking at the curvy, pointy light on the tea surface. This is also what you call the light patterns in the shadow of a glass and wavering at the bottom of a pool.
Reaction-diffusion
These wiggly lines are a reaction-diffusion system of air bubbles between two panes of glass in a layered piece of art by Dustin Yellin. This type of wiggly pattern also happens in places like bird feathers, rabbitfish scales, and shriveled paint.
Angle of repose
The dirt in this pile is showing off its angle of repose: the slope that a pile of granules forms when it is “at rest”. You can watch for the angle of repose when you shovel snow and throw it in a pile, or when you build sandcastles, depending on where you happen to live right now.
Read more
My friend Dan is writing about geometrical curiosities on his blog. My favorite post so far is an introduction to pseudospheres and tractrices.
Vi Hart makes lots of related projects including looking at the hyperbolic shriveling of dried apple slices.
Bonus words
Non-geometry-related things to find and name: bollards, wall ties, ghost signs, perforated screen walls, former Fotomats, benchmarks (find some near you), manicules, telephone exchange buildings, skeuomorphs in general. And obsolete technologies that are still in use or still visible: sidewalk prisms, Quonset huts, civil defense air sirens, glass insulators, old-style phone numbers.
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saturday, september 06, 2008
Top 2 Fractals and Top 10 Tags
Inspired by a thread in the Delicious forum, here’s another [slightly self-indulgent] thing to post on your blog: annotate your Top 10 Tags on Delicious. These are mine.
- *broken — I add this tag to bookmarks that have rotten links.
- silly — I think these bookmarks are amusing, dumb, or both.
- photos — I like looking at pictures.
- transport — I enjoy learning about ways that people go from place to place.
- food — I’m interested in what people eat.
- web — This is supposed to be a tag for websites that engage with the nature of the web, or something like that.
- books — I care about questions like “What are books?” and “What role do they play?” and that’s pretty much why I’m a Literature student.
- architecture — I enjoy learning about places that people build.
- animals — I’m interested in how people interpret and relate to animals.
- drawings — I like looking at pictures.
Update: Thanks to Lauren Sperber and Edward Vielmetti for taking this up!
