Questions tagged [topology]
A puzzle about disentangling knots, folding paper, separating strings and wires, and understanding the connectivity properties of elastic figures. General topology questions are off-topic but can be asked on Mathematics Stack Exchange.
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Changing baby's shirt
Baby needs a change of shirt, but baby is also sucking on a bottle (see this stock photo for a visual). If the bottle leaves baby's mouth, baby will start crying. Also, baby loves holding the ...
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Smallest Unicode Box Drawing
What is the smallest box diagram you can draw which uses all of the Unicode box drawing characters at least once, but without leaving any loose ends? For reference, you must use each of these ...
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Is there a proof that a map of the United States requires 4 colors?
The Four color theorem states that no more than four colors are required for any map. Can it be proved or disproved that 3 colors can be used for United States map?
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IQ Test Example
I'm reading up on various IQ tests, and a slideshow that I stumbled upon gave the following example:
This doesn't make sense to me, as none of the options duplicate the conditions in the far left ...
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Turning My Pants Inside-Out
A 12-foot long rope has two ends. One end of the rope is tied around a man's left ankle and the other end is tied around the man's right ankle.
If you are not allowed to untie the rope and you're ...
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It boggles my mind
Part of the Monthly Topic Challenge #10: Möbius Strips, Klein Bottles, and other unusual topological surfaces
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Ernie and the Underground Network
I haven't seen Ernie for a few weeks - he's been on holiday in the People's Republic of Kzijekistan (PRK). But yesterday I got an e-mail and thought I would share it with you. It reads as follows:
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Connect the colored dots
I've got this:
By connecting the dots, I get this:
Could you do the same for this one:
There is a unique solution.
The rules are: You have to use every square, lines can't cross each other and you ...
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The three utilities puzzle
Here is a variant of the three utilities puzzle.
Famously, It is impossible to solve it on a plane paper (Euler's theorem can prove that). But can you solve it on a coffee mug?
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3D ring/rope wooden puzzle solution?
I have a Eureka 3d "Puzzle G":*
The box lists 3 puzzles:
Remove the ring
Remove the rope
Move the ring to the other side
While I was able to solve shows the first puzzle, I haven't ...
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How to generalise hang picture puzzle?
There is well known problem:
The picture is attached to a string and you want to hang it on N nails so that if one takes out any of the nails, the picture falls. How do you do it?
For those who ...
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Dragon summoning spell
The parchment shown below got stained with something. See if you can determine the obscured parts.
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Toroidal tic-tac-toe
Part of the Monthly Topic Challenge #10: Möbius Strips, Klein Bottles, and other unusual topological surfaces
Warm-up for topological thinking. You are playing tic-tac-toe with the usual 3x3 grid,...
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Drawing a complete graph of 5 nodes on a torus
A complete graph of $n$ nodes is a graph where every node is connected to every other node. It is known that one cannot draw a complete graph of 5 nodes on a piece of paper (plane) without any ...
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How to use a Mobius strip for puzzle creation? [closed]
A Mobius strip is one of the basic concepts of topology. There are many interesting tricks using this strip (for example, interesting results of cutting the tape with a different number of turns). ...
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