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Inventing an algebraic knot theory for eight year olds (III)

46 pointsby theaeolistabout 10 years ago

8 comments

mrcactu5about 10 years ago
While at Cambridge, Thomas Fink wrote &quot;The 85 Ways to Tie a Tie: The Science and Aesthetics of Tie Knots&quot; (2001)<p><a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;The-85-Ways-Tie-Aesthetics&#x2F;dp&#x2F;1841155683" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;The-85-Ways-Tie-Aesthetics&#x2F;dp&#x2F;18411556...</a><p>He connects his model of neckties to statistaical mechanics and invents a few new styles.<p><a href="http:&#x2F;&#x2F;www.tcm.phy.cam.ac.uk&#x2F;~tmf20&#x2F;85ways.shtml" rel="nofollow">http:&#x2F;&#x2F;www.tcm.phy.cam.ac.uk&#x2F;~tmf20&#x2F;85ways.shtml</a> <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;The_85_Ways_to_Tie_a_Tie" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;The_85_Ways_to_Tie_a_Tie</a>
oldbuzzardabout 10 years ago
DS8 and I have recently been enjoying Christopher Zeeman&#x27;s[1] Royal Institution Christmas Lectures[2]. The first one on linking and knotting has the same flavor as the article and could be a good intro for parents doing this at home.<p>[1]<a href="http:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Christopher_Zeeman" rel="nofollow">http:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Christopher_Zeeman</a> [2]<a href="http:&#x2F;&#x2F;richannel.org&#x2F;christmas-lectures&#x2F;1978&#x2F;1978-christopher-zeeman" rel="nofollow">http:&#x2F;&#x2F;richannel.org&#x2F;christmas-lectures&#x2F;1978&#x2F;1978-christophe...</a>
j2kunabout 10 years ago
Submitting in the comment box on the blog failed with &quot;Could not open socket,&quot; so I&#x27;ll post my question here.<p>Now that you have a notation (even if it may not be complete, you&#x27;ve raised the question in exercise 5), I am curious about computation.<p>1. Given two knots that are describable in this notation, is there an algorithm that decides if they are equivalent?<p>2. If so, what is the known (time&#x2F;space) complexity of this problem?
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ul5255about 10 years ago
Why is the left-most portion in the picture: <a href="http:&#x2F;&#x2F;researchblogs.cs.bham.ac.uk&#x2F;thelablunch&#x2F;files&#x2F;2015&#x2F;05&#x2F;overhandalg.png" rel="nofollow">http:&#x2F;&#x2F;researchblogs.cs.bham.ac.uk&#x2F;thelablunch&#x2F;files&#x2F;2015&#x2F;05...</a><p>I x C: (3,3) and not I x C: (1,3) ?<p>Similarily the right-most one should be C* x I: (3,1) no?
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pfortunyabout 10 years ago
Eight year olds is a bit of an overstretch, after reading the notation and descriptions...
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octatoanabout 10 years ago
Is the unknot (as in, a loop) representable in this notation?
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ColinWrightabout 10 years ago
Not loading for me - has it collapsed under the load already?
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ameliusabout 10 years ago
Anybody got the formula for tying a tie?