Category Archives: Uncategorized

Graph minors

This is now, at the time of writing, the longest article on cp4space. We’ll begin with a very well-known problem, which asks whether it’s possible for three houses on the plane to be connected to three utility suppliers without crossings. What appear … Continue reading

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Alexandroff line

If this isn’t one of Ben Elliott and Hunter Spink’s bizarre mathematical objects of the week, it certainly deserves to be. This is a strange object which locally behaves like the real line, but is much longer. Instead of considering … Continue reading

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Generalised Truchet tiles

A long time ago, in a monastery far away, a monk called Sebastian Truchet decided to create patterns by tiling a square grid with a single type of tile (in two orientations). For instance, one possible pattern of 64 Truchet … Continue reading

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Bombers and Basilisks

Tim Hutton has announced the release of Ready 0.5, which is now able to support cellular automata and reaction-diffusion systems on three-dimensional honeycombs. There are a few sample patterns on Penrose tilings as well. Replicators and Feynman diagrams On the subject … Continue reading

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Topological tacks

If you’ve bought a box of drawing pins from a stationery store, you’ll observe that the pins do not pack tightly at all, and there is lots of empty space in there. Indeed, it’s impossible to pack them particularly efficiently, … Continue reading

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Egmohedron

Partially inspired by the chiral icosahedral sculptures by George Hart and Bathsheba Grossman, I have decided to create one of my own. It’s composed of thirty identical components, each of which is a distorted lemniscate. Note that the lemniscate has … Continue reading

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Recapping 2012

Now that the year is drawing to a close, there are a few things worth discussing. Firstly, cp4space has a total of over 20000 views and a new seasonal banner (see above)! Mathematica 9 The Treefoil has been mentioned on mathpuzzle.com. … Continue reading

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The inadequacy of SCLT

As I mentioned a few posts ago, I included the Diophantine equation x^4 + y^6 = z^10 on the Advanced Mentoring Scheme. I’m not going to spoil it here, although I have since been informed that I had previously included it … Continue reading

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The world still exists

It transpires that the world didn’t actually end yesterday. At the very least, Descartes’ famous deduction ‘cogito ergo sum’ seems to imply that. To summarise, the Mayan calendar has finished its 13th long count cycle; equivalently, 13×20×20×18×20 days have passed since … Continue reading

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Dissecting the disc

At the tenth Gathering for Gardner, Colin Wright proposed the following problem. It’s quite well known, and I believe it has been published elsewhere before: ‘Dissect a [unit] disk into congruent parts at least one of which avoids the center by … Continue reading

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