Portal:Mathematics/Suggestions

Images must have proper free use tags - no fair use or deprecated tags.

Image:Discriminant real part.jpeg|Real part of the modular discriminant on the unit circle

Image:Complex_gamma_function_abs.png|Absolute value of the gamma function on the complex plane

Image:TetraOctaHoneycomb-VertexConfig.svg|The vertex configuration of a tetrahedral-octahedral honeycomb

Image:Stereographic polytope 24cell faces.png|Stereographic projection of a 24-cell

Image:Alexander horned sphere.png|Alexander horned sphere

Image:13-Weak-Orders.svg|13 weak orders

Image:Hyperbolic_tiling_cantellated_3-7.png|View of regular hyperbolic tiling cantellated {3,7}

Image:Cantel 24cell1.png|Cantellated 24-cell stereo projection wireframe

Image:Bigyrate diminished rhombicosidodecahedron.png|Bigyrate diminished rhombicosidodecahedron (Johnson solid #79)

Image:Stella octangula.png|Stella octangula / Star Tetrahedron

Image:Sixth stellation of icosahedron.png|Sixth stellation of the icosahedron

See also: :Category:Mathematics images

Note: Portal:Mathematics/Upcoming featured pictures now lists upcoming months, so any appropriate image can actually be placed "in the queue" to appear as a future "Picture of the month".

User:David Eppstein has a collection of his many DYK items.  Kiefer.Wolfowitz 13:55, 2 May 2011 (UTC)

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• File:Kawasaki's theorem.jpg... that according to Kawasaki's theorem, an origami crease pattern with one vertex may be folded flat (pictured) if and only if the sum of every other angle between consecutive creases is 180º? (11.04)
• ... that John R. Isbell was the primary contributor to the mathematical theory of uniform spaces? (11.04)
• ... that Edgar Gilbert investigated the mathematics of shuffling playing cards? (11.03)
• ... that, in the Rule 90 cellular automaton, any finite pattern eventually fills the whole array of cells with copies of itself? (11.02)
• ... that The Princeton Companion to Mathematics is the 2011 winner of the Mathematical Association of America's Euler Book Prize? (11.02)
• ... that block cellular automata, invented by Norman Margolus, can be used to simulate lattice gases, sand piles, and billiard-ball computers? (11.02)
• ... that Andreu Mas-Colell, currently the Minister of Economy and Knowledge of Catalonia, Spain, has studied general equilibrium theory by using differential topology? (11.01)
• ... that Graciela Chichilnisky, who proposed the Kyoto Protocol's market for carbon credit trading, obtained her PhDs in mathematics and economics without ever having been an undergraduate? (11.01)
• ... that Starr's corollary to the Shapley–Folkman lemma was proved by an undergraduate student of Kenneth Arrow? (10.10)
• ... that Paul Erdős challenged Jon Folkman to solve mathematical problems immediately after Folkman's surgery for brain cancer? (10.10)
• ... that every round-robin tournament either has a set of players who win all games against players outside the set, or its graph of wins and losses is pancyclic, having directed cycles of all lengths? (10.09)
• File:Pizza theorem1.jpg... that, according to the pizza theorem, a circular pizza that is sliced off-center into eight equal-angled wedges can still be divided equally between two people? (09.12)
• ... that the clique problem of programming a computer to find complete subgraphs in an undirected graph was first studied as a way to find groups of people who all know each other in social networks? (09.12)
• ... that Matthew T. Dickerson is a computational geometer, scholar of J. R. R. Tolkien and the Inklings, novelist, blues musician, fly fisherman, maple sugar farmer, and beekeeper? (09.11)
• File:Herschel graph.svg... that the Herschel graph (pictured) is the smallest possible polyhedral graph that does not have a Hamiltonian cycle? (09.10)
• ... that Martin Demaine founded the first one-man art glass studio in Canada and home-schooled his son Erik to become MIT{{'}}s youngest ever professor despite not having a college degree himself? (09.09)
• ... that the Life without Death cellular automaton, a mathematical model of pattern formation, is a variant of Conway's Game of Life in which cells, once brought to life, never die? (09.06)
• File:Calkin-Wilf_spiral.svg... that one can list every positive rational number without repetition by breadth-first traversal of the Calkin–Wilf tree? (09.05)
• ... that the first textbook in Hungarian, an encyclopedia by János Apáczai Csere, was written and published in the Netherlands? (09.03)
• File:Hadwiger covering.svg... that the Hadwiger conjecture (diagram pictured) implies that the surface of any three-dimensional convex body can be illuminated by only eight light sources, but the best proven bound is that 16 lights are sufficient? (09.03)
• File:Equitable-K15.svg... that an equitable coloring of a graph (pictured), in which the numbers of vertices of each color are as nearly equal as possible, may require far more colors than a graph coloring without this constraint? (09.03)
• ... that no matter how biased a coin one uses, flipping a coin to determine whether each edge is present or absent in a countably infinite graph will always produce the same graph, the Rado graph? (09.03)
• ... that there are 115,200 solutions to the ménage problem of permuting six couples at a twelve-person table so that men and women alternate and are seated away from their partners? (09.01)
• File:Hadwiger conjecture.svg... that mathematician Paul Erdős called the Hadwiger conjecture, a still-open generalization of the four-color problem, "one of the deepest unsolved problems in graph theory"? (08.05)
• ...that Dutch topologist Johannes De Groot is the academic grandfather, great-grandfather, and great-great-grandfather of his namesake via four different paths of academic supervision? (08.04)
• ...that Carl Størmer, "the acknowledged authority" on aurorae and the motion of charged particles in the magnetosphere, began his academic career inventing formulae for π? (08.03)
• ...that in Floyd's algorithm for cycle detection, the tortoise and hare move at very different speeds, but always finish at the same spot? (07.10)
• ...that in graph theory, a pseudoforest can contain trees and pseudotrees, but cannot contain any butterflies, diamonds, handcuffs, or bicycles? (07.10)
• Image:Möbius–Kantor unit distance.svg...that it is not possible to configure two mutually inscribed quadrilaterals in the Euclidean plane, but the Möbius–Kantor graph (pictured) describes a solution in the complex projective plane? (07.09)
• ...that the six permutations of the vector (1,2,3) form a hexagon in 3d space, the 24 permutations of (1,2,3,4) form a truncated octahedron in four dimensions, and both are examples of permutohedra? (07.08)
• ...that the Rule 184 cellular automaton can simultaneously model the behavior of cars moving in traffic, the accumulation of particles on a surface, and particle-antiparticle annihilation reactions? (07.05)

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Image:2dCCA-n16.png

• ...that a cyclic cellular automaton (pictured) is a system of simple mathematical rules that can generate complex patterns mixing random chaos, blocks of color, and spirals? (07.04)
• ...that a nonconvex polygon with three convex vertices is called a pseudotriangle? (07.04)

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Here are some DYK associated with me:

Did you know?

• ... that Jurassic Park{{'s}} discussion of chaos theory was inspired by Ivar Ekeland?21 April 2011 ([http://stats.grok.se/en/201104/Ivar_Ekeland 4.1k Visitors])
• ... that Robert Phelps is a "grandfather" of modern variational principles, according to Ivar Ekeland? 13-14 April 2011([http://stats.grok.se/en/201104/Robert_Phelps 0.7k Visitors])

• ... that, while the criss-cross algorithm visits all eight corners of the Klee–Minty cube when started at a worst corner, it visits only three more corners on average when started at a random corner? 4 April 2011
• ([http://stats.grok.se/en/201104/Criss-cross_algorithm 4.4k Visitors to Criss-cross algorithm])
• ([http://stats.grok.se/en/201104/Klee–Minty_cube 5.8k Visitors to Klee–Minty cube])

• ... that economists blame market failures on non-convexity? 7 February 2011 [http://stats.grok.se/en/201102/Non-convexity_(economics) 2.5k Visitors]

• ... that Henry Mann{{`s}} 1949 book, Analysis and design of experiments, filled mathematical gaps in the statistical writings of Ronald A. Fisher? 1 February 2011 [http://stats.grok.se/en/201102/Henry_Mann 1.2k Visitors]
• ... that Andreu Mas-Colell, currently the Minister of Economy and Knowledge of Catalonia, Spain, has studied general equilibrium theory by using differential topology? 30 January 2011 [http://stats.grok.se/en/201101/Andreu_Mas-Colell 765 Visitors]
• ... that Graciela Chichilnisky, who proposed the Kyoto Protocol's market for carbon credit trading, obtained her PhDs in mathematics and economics without ever having been an undergraduate? 27 January 2011 [http://stats.grok.se/en/201101/Graciela_Chichilnisky 2.3k Visitors]

• ... that Starr's corollary to the Shapley–Folkman lemma was proved by an undergraduate student of Kenneth J. Arrow (pictured)? 28 October 2010 [http://stats.grok.se/en/201010/Shapley–Folkman_lemma 3.6k Visitors]

• ... that Paul Erdős (pictured) challenged Jon Folkman to solve mathematical problems immediately after Folkman's surgery for brain cancer? 28 October 2010 [http://stats.grok.se/en/201010/Jon_Folkman 2.6k Visitors]

• ... that mathematician Lennart Carleson (pictured) received his Ph.D. when he was 22 years old and later supervised the thesis of Svante Janson, who received his first Ph.D. on his 22nd birthday? 6 July 2010 [http://stats.grok.se/en/201007/Svante_Janson 1.3k Visitors]

:::—;I've crossed out those here which are already used. ―JuPitEer (talk) 14:32, 2 November 2012 (UTC)