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Ancient Puzzle Gets New Lease on 'Geomagical' Life

techbeat writes "An ancient mathematical puzzle has found a new lease on life, reports New Scientist. The magic square is the basis for Sudoku, pops up on the back of a turtle in Chinese legend and provides a playful way to introduce children to arithmetic. But all this time it has been concealing a more complex geometrical form, says recreational mathematician Lee Sallows. He recently released dozens of examples of his 'geomagic squares' online. 'To come up with this after thousands of years of study of magic squares is pretty amazing,' blogged author Alex Bellos. Magic squares are used to help create codes for transmitting information and in the design of drug trials so geomagic ones may have real-world uses, says mathematician Peter Cameron. New Scientist has also put up a gallery of the geomagic squares."

44 of 73 comments (clear)

  1. Not exactly a turtle by jsse · · Score: 4, Informative

    It was no ordinary turtle. It is called a dragon turtle which is huge in size with a dragon head: http://www.kunde.org.tw/image3/01-book-032.jpg

    Legend said that it carried strange messages on its shell. The messages looked simple (as you can see in the picture above) but people later found the complex meanings behind them.

    This messages are the building blocks of most numerologies in ancient China, including Fengshui and I-Ching.

    This is one of the most famous OPA (Out of Place Artifact) in China history.

    1. Re:Not exactly a turtle by Sulphur · · Score: 1

      It was no ordinary turtle. It is called a dragon turtle which is huge in size with a dragon head: http://www.kunde.org.tw/image3/01-book-032.jpg

      Legend said that it carried strange messages on its shell. The messages looked simple (as you can see in the picture above) but people later found the complex meanings behind them.

      This is one of the most famous OPA (Out of Place Artifact) in China history.

      If it were a mock turtle, would the messages be wrong mockingly?

    2. Re:Not exactly a turtle by derGoldstein · · Score: 1

      It was no ordinary turtle. It is called a dragon turtle which is huge in size with a dragon head

      Well there's a fat bald guy riding this one, so I can't read what its shell says. Damn it, there's always a fat guy in the way.

      --
      Entomologically speaking, the spider is not a bug, it's a feature.
    3. Re:Not exactly a turtle by TheABomb · · Score: 1

      Is that Boom Boom riding a Koopa Troopa?

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      MSIE: The world's most standards-complaint web browser.
    4. Re:Not exactly a turtle by TheABomb · · Score: 1

      Not the Fonz.

      --
      MSIE: The world's most standards-complaint web browser.
  2. His writing style is atrocious. by lxs · · Score: 1

    I went to the site to find out what geomagic squares are, but by the time I reached the end of the summary I completely lost interest.

    1. Re:His writing style is atrocious. by Anonymous Coward · · Score: 2, Insightful

      I went to the site to find out what geomagic squares are, but by the time I reached the end of the summary I completely lost interest.

      Oh no, not his writing style. Fucking idiot - look at his gallery, its actually very clever and not everyone can afford a writing staff to get past the crap filter on morons like you (which I assume is a self-feeding mechanism, as you keep getting spoon fed BS by such filters throughout your life you will only ever know such). Swearing for your benefit in hopes to publicly degrade you while making you stop reading at the first line.

    2. Re:His writing style is atrocious. by wrencherd · · Score: 1

      And yet his explanation is still a lot more understandable than TFA.

    3. Re:His writing style is atrocious. by mr_gorkajuice · · Score: 1

      Improving slashdot, step one: disable anonymous comments.

    4. Re:His writing style is atrocious. by tkprit · · Score: 1

      Easy to understand, but not exactly... enthusiastic?

      A similar site (and they're also promoting a book), prime curios, exudes enthusiasm imo, encourages user input, and I think promotes interest in math. I think the 'geomagical' site could use some editors (which prime curios probably utilizes).

    5. Re:His writing style is atrocious. by 2.7182 · · Score: 1

      I read the whole article and found it entirely not terribly original or interesting. Sure, maybe you can make a code from it. I can generate tons of weird combinatorial/geometric widgets that do the same thing.

    6. Re:His writing style is atrocious. by Ironchew · · Score: 1

      Improving slashdot, step one: disable anonymous comments.

      You know you can set modifiers on AC comments in your preferences, right? -3 is a good setting.

  3. Recreational Mathematician? by jellyfrog · · Score: 2

    Sounds suspicious. Oh I bet it's 'perfectly safe', but you start out on math and who knows where you'll end up? Smoking crack out of rolled up nonstandard analysis theorems in a gutter in cambridge? It's a gateway drug, I tell ya.

    1. Re:Recreational Mathematician? by derGoldstein · · Score: 1

      Recreational Mathematics is a form of masochism. It's no different then those guys that whip their own backs or who go to those clubs where everyone wears black leather. It's sick and twisted, but there's nothing we can do about it, since they're technically only hurting themselves.

      --
      Entomologically speaking, the spider is not a bug, it's a feature.
    2. Re:Recreational Mathematician? by Yvanhoe · · Score: 2

      Yep. On the other hand, programming for fun is a lot more sane.

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
  4. New Scientist = odd number fail by wickerprints · · Score: 1

    Check it out on page 5 of the New Scientist link. Apparently, they think 8 is an odd number, and 9 and 11 are not. So much for the "new math."

    1. Re:New Scientist = odd number fail by DarthJohn · · Score: 1

      Also on that page: 1 + 3 + 5 + ... + 15 + 17 = 3.3^3
      wtf?
      if I do 1+3+5+7+9+11+13+15+17 I get 81 which is 3^4

    2. Re:New Scientist = odd number fail by wickerprints · · Score: 2

      By 3.3^3, they mean 3 x 3^3, not (3.3)^3. It's an unfortunate use of the period symbol to denote multiplication because standard keyboards do not have the centered dot symbol.

    3. Re:New Scientist = odd number fail by eyeoftheidol · · Score: 2

      Yes, but they want to express it as 3.3^3 to bring out the relationship with a 3.3 shape (ie, a square). (You are reading "3.3" as "3 multiplied by 3", aren't you?)

    4. Re:New Scientist = odd number fail by DarthJohn · · Score: 1

      I read it as "three and three tenths," didn't know there was another way to read that. Thanks for the tip.

    5. Re:New Scientist = odd number fail by wickerprints · · Score: 2

      Ah, because they want to emphasize the fact that the "sum" of the figures in a given row, column, or diagonal is a 3x3x3 cube, and thus the total number of cubic units is three times the sum of a single row/column, or 3 x 3^3, which in turn is the sum of the nine consecutive odd integers from 1 to 17, which form the individual entries of the geomagical square.

    6. Re:New Scientist = odd number fail by tkprit · · Score: 1

      ^

      THIS is why you read /. @ full ...pls MOD UP!

    7. Re:New Scientist = odd number fail by tkprit · · Score: 1

      &#183 (and I think even &middot) has worked fine in HTML for years (albeit not on /. for some reason). I use parentheses, dots, and carets myself, (or enter it in http://www.wolframalpha.com/ and copy the pretty mathematically-correct image), but I'm not New Scientist.

    8. Re:New Scientist = odd number fail by techbeat · · Score: 1

      Thanks very much for pointing this out. I edited the story for New Scientist and it's fixed now.

  5. Re:I like turtles... by derGoldstein · · Score: 1

    Someone's going to say it, so it might as well be me: It's turtles all the way down!

    Oh, and I was going to use Italic instead of bold text, but the <i> doesn't seem to work in the new design... or maybe it's just me.

    --
    Entomologically speaking, the spider is not a bug, it's a feature.
  6. Re:This layout sucks by M8e · · Score: 1

    Yeah, get a goat!

  7. Re:This layout sucks by burisch_research · · Score: 1

    This is a bug caused by having a long slashdot username. The long username means that the left menubar is extra-wide, and covers the main content pane. I have reported this issue, so maybe we'll get a fix one day.

    --
    char*f="char*f=%c%s%c;main(){printf(f,34,f,34);}";main(){printf(f,34,f,34);}
  8. Just a square? by Rashdot · · Score: 1

    So he hasn't found the Time Cube yet...

    --
    This is not the sig you're looking for.
  9. Re:This layout sucks by Phreakiture · · Score: 1

    Looks fine in Firefox.

    That said, I think it could be argued that sites are getting too complex, causing them to take too long to load and very prone to misrendering.

    --
    www.wavefront-av.com
  10. Re:This layout sucks by justleavealonemmmkay · · Score: 1

    Looks fine in Firefox.

    That's because your username is short

  11. Re:Magic Squares in n dimensions by gilleain · · Score: 1

    Interesting, but these 'geomagic squares' of Lee Swallows are generalised in a different way. It is the dimension of the elements of the square, not the square itself. So, in his formalism, numerical magic squares (of any dimension) are just 1-D geomagic squares, where the numbers could represent line segments or arcs of a circle.

  12. Re:Magic Squares in n dimensions by AshtangiMan · · Score: 1

    Hmmm . . . the 2x2 square at the end is represented by arcs in circles, which I am not at all understanding. But maybe there were the appropriate number of arcs to represent the line segments . . . I still don't see how that relates to the 3x3 and 4x4 squares.

  13. Nice work, but incomplete? by degeneratemonkey · · Score: 1

    I think this guy's work can be abstracted even further.

    I'm no mathematician, but I see no reason to stop at geometric shapes. It seems to me that any arbitrary set T with an addition operator defined over it has the potential to be a space in which magic squares can be found. In the case of this guy's work, that set happens to be the set of n-dimensional geometric shapes with the addition operator defined as a geometric union. In traditional magic squares, that set is simply {x : 0 x 10}.

    1. Re:Nice work, but incomplete? by degeneratemonkey · · Score: 1

      Arrrg! Ahem, { x : 0 < x < 10 }

    2. Re:Nice work, but incomplete? by Natlaw · · Score: 1

      He does give that in the more formal definition in the appendix: http://www.geomagicsquares.com/appendix.php

    3. Re:Nice work, but incomplete? by degeneratemonkey · · Score: 1

      I'm not sure about the technical definition of "well-defined" if there is a specific one in the case of an addition operation. I assume that for n-dimensional volumes, it is sufficient to define addition as a union of two volumes (a volume being a bounded infinite set in R^n).

    4. Re:Nice work, but incomplete? by degeneratemonkey · · Score: 1

      I really hate not being able to edit /. posts. On second thought, I would more succinctly define an n-dimensional volume as any subset of R^n. Addition would still be a simple set union.

    5. Re:Nice work, but incomplete? by degeneratemonkey · · Score: 1

      Thanks, totally missed that. This is great, and I would actually be interested to see it generalized over n-dimensional "magic" structures (i.e. magic hybercubes). At some point it feels like mental masturbation, but interesting no less.

  14. ACs can have great comments by tkprit · · Score: 2

    Some of the best comments I've ever read on /. were by ACs. Just sayin' :)

  15. Recreational Mathematician! by tkprit · · Score: 1

    LOL, thank you! I do the occasional diffy Q just to relax, as well as code 'for fun' (well, I don't get paid anyway).

    (Well, I also do diffy Qs keep up skills so I can make sure I stay ahead of my kids, who apparently aren't overly fond of mathematics. If you don't use it, ya LOSE it :D )

  16. What the... by cvnautilus · · Score: 1

    What the hell? I RTFA and have no idea what this is about. What is a polymino? Guess what? I still think it's a horse.

  17. Hard Drop by tepples · · Score: 1

    You're thinking of "Palomino". See "Piece" on Hard Drop.

  18. pentalobular containment by epine · · Score: 1

    Not much excitement in this thread.

    Last week I spent nearly a full day on Knuth's Dancing Links algorithm in relation to a combinatorial problem in coding theory (it's not a strong fit, but I thought there might be a stray intuition).

    This little divertimento lead me to discover some clever tricks in how to set up the Dancing Links matrix for a certain class of problems to avoid traversing symmetric solutions. Considering the apathy level on this story, it would be a waste of breath to spell it out here.

    It's cute, but the guy is trying to make a bit too much of it. For me it's just a toy problem in simultaneous exact cover that lends itself to visual aphorisms.

    Maybe he could do a 4x4x4x4 grid of Wang tiles (I'm thinking 4D cubes with coloured faces) where every 1x1x4x4 subslice of 16 Wang cubes can be assembled into a 2x2x2x2 hypercubelet with every 2x2 face of the target cubelets conforming to some property, such as colours all same, or colours all different, and the 24 assembled cubelets (if my math is right, and it always is--in cartoon world) form some interesting tour of the 24 palladium quasi-crystals oscillation nodes.

    Anyone? It's the key to pentalobular Arc reactor containment, for anyone with a giant pile of mil-scrap.

    1. Re:pentalobular containment by lennier · · Score: 1

      the 24 palladium quasi-crystals oscillation nodes.

      Anyone? It's the key to pentalobular Arc reactor containment, for anyone with a giant pile of mil-scrap.

      Tony Stark, is that you?

      --
      You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC