
Recent Posts
Subscribe to Complex Projective 4Space
Archives
 September 2021
 July 2021
 June 2021
 May 2021
 February 2021
 January 2021
 December 2020
 November 2020
 October 2020
 September 2020
 August 2020
 July 2020
 June 2020
 May 2020
 June 2019
 May 2019
 March 2019
 November 2018
 September 2018
 July 2018
 June 2018
 May 2018
 April 2018
 March 2018
 February 2018
 November 2017
 October 2017
 November 2016
 May 2016
 March 2016
 February 2016
 December 2015
 September 2015
 March 2015
 February 2015
 January 2015
 December 2014
 November 2014
 October 2014
 September 2014
 August 2014
 July 2014
 June 2014
 May 2014
 April 2014
 March 2014
 February 2014
 January 2014
 December 2013
 November 2013
 October 2013
 September 2013
 August 2013
 July 2013
 June 2013
 May 2013
 April 2013
 March 2013
 February 2013
 January 2013
 December 2012
 November 2012
 October 2012
 September 2012
 August 2012
Recent Comments
 Martin Andersen on The neural network of the Stockfish chess engine
 Danny Winters on Final chapter of MODA
 Ross Presser on Hamming backups: a 2of3 variant of SeedXOR
 An efficient prime for numbertheoretic transforms  Complex Projective 4Space on Complexity of integer multiplication almost solved
 SuperSupermario24 on Infinite monkey theorem
Monthly Archives: January 2013
Graph minors
This is now, at the time of writing, the longest article on cp4space. We’ll begin with a very wellknown 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
Posted in Fastgrowing functions, Uncategorized
Leave a comment
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
Posted in Uncategorized
Leave a comment
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
Posted in Uncategorized
Leave a comment
Cipher 11: Musical mayhem
This cipher again is separated into two parts, namely an audio file and the following ciphertext. ZKIGPWQ SLZSIIJ PBJRQKI TIMFTBE PEIVCNP CVHFEHA OAXINDB PTGDPUO PSJRBEP ZAAAAAA Unless you’re pitch perfect, you might also find this useful: I’ll leave you to work out … Continue reading
Posted in Ciphers
Leave a comment
Bombers and Basilisks
Tim Hutton has announced the release of Ready 0.5, which is now able to support cellular automata and reactiondiffusion systems on threedimensional honeycombs. There are a few sample patterns on Penrose tilings as well. Replicators and Feynman diagrams On the subject … Continue reading
Posted in Uncategorized
Leave a comment
The Ξ function
This is the final article on fastgrowing functions. In the first two articles we looked at computable functions, up to and including Friedman’s TREE function. The third article described the Busy Beaver function, which eventually overtakes all computable functions. This … Continue reading
Posted in Fastgrowing functions
Leave a comment
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
Posted in Uncategorized
Leave a comment
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
Posted in Uncategorized
Leave a comment
Cipher 10: 2013
Assuming that this has been timed correctly, it should appear after the first minute of the first day of the new year. To celebrate this, today’s cipher is simply a matrix of 2013 binary digits. I’ll include this in both a … Continue reading
Posted in Ciphers
Leave a comment