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Meta
Category Archives: mathematics
the greatest thing ever!
Forgive my waxing hyperbolic . . . This is a tiling of the hyperbolic plane by triangles whose angles are π/2, π/3, π/7 – the smallest possible tile. I present it in a conformal mapping analogous to the Mercator projection, which I’ve … Continue reading
Posted in eye-candy, mathematics
1 Comment
looking for sanity checks in an insane world
Some years ago, using basic theorems of hyperbolic trigonometry, I worked out a conformal representation of the hyperbolic plane which preserves one line – analogous to the Mercator projection of the sphere, a conformal map which preserves one great circle. … Continue reading
Posted in mathematics
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symmetries made simple
This may be of interest to only a few: Simplest Canonical Polyhedra of Each Symmetry Type (rotable in Java); in other words, canonical forms of the simplest topologies that allow the specified symmetries and none higher. Any convex polyhedron can … Continue reading
Posted in mathematics
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negative curves
For years I’ve wished to learn enough hyperbolic geometry to write a simple ray-tracer. Recently a post on comp.graphics.algorithms advised me to look up Euclidean and Non-Euclidean Geometry by Patrick J. Ryan; I was pleased to find that its subtitle … Continue reading
Posted in mathematics
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non c’è più religione
Tsk. A current radio spot gives the web address “wachovia dot com backslash new”. Meanwhile, what’s new with me? I’m reading Coxeter’s Non-Euclidean Geometry in the hope that it will give me the stuff I’ve sought in vain in other … Continue reading
Posted in mathematics, me!me!me!, neep-neep, pets
3 Comments
just don’t throw it indoors
Vladimir Bulatov makes and sells pretty things in metal, wood and stained glass. I haven’t bought any of them — yet!
Posted in eye-candy, mathematics
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C(52,5)
Played poker last night – for the second time in my life, if I haven’t miscounted – with some Stanfordites; I think I was the only one there over thirty. Won $2.50.
Posted in California, mathematics, me!me!me!
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