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Meta
Category Archives: mathematics
it’s all connected
My old calculus book gives a formula for the curvature of a parametric arc in the plane — that is, an arc defined by two functions (x(t),y(t)) of one variable. For thirty years I didn’t think about the derivation of … Continue reading
Posted in curve-fitting
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better my computer than me
My computer ran for eight solid days to extend this table from six rows — (2 3 7), (2 4 5), (3 3 4), (2 3 ∞), (2 ∞ ∞), (∞ ∞ ∞), each of which is (in some sense) … Continue reading
Posted in mathematics
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soap films in curved space
A few of the many triply periodic minimal surfaces can be generated from a quadrilateral slice through a tetrahedron of mirrors, as refined by Surface Evolver. I had the idea that the same concept, applied to one of the analogous … Continue reading
Posted in mathematics
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but wait there’s more
This one is a projection of a design on (half of) the surface of a hypersphere: a ribbon spans two orthogonal great circles, wrapping three times around one and five times around the other. Kitty teeth did break it at … Continue reading
Posted in mathematics, merch
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Baby’s First Klein Bottle™
Not only did it not fall apart in my hands …
Posted in mathematics, merch
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first tangible result
The strand — for it is a Klein bottle woven of a single strand — is thinner than I expected, and has broken in at least two places. Ah well, live and learn; I’ve already redesigned it to be more … Continue reading
Posted in mathematics, merch
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Gray palette
I came up with this concept several years ago (I can’t tell exactly when, because I’ve mislaid the original code!) but never posted any of the images until now. Some of you may like to guess what’s going on before … Continue reading
Posted in mathematics
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