Talk:Ropelength
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I was wandering whether we should use the term 'ropelength' as written together, since this is how most of literature, I have seen, used. Iswyn 02:24, 22 May 2007 (UTC)
- First, thank you for writing this article. Second, I believe we should move to "ropelength". Someone moved the article to "rope length" claiming it was 10 time times more common in Google Scholar. However, when I looked in Google Scholar, it was clear a majority of the hits had very little to do with this knot theoretic idea of rope length, and even the ones that did were mainly not by knot theorists. A Google scholar search for ' "rope length" + knot' and weeding out extraneous hits (such as patent applications on rope using devices) is more revealing. In comparison, a Google Scholar search for "ropelength" brings up far more knot theoretic hits, and it's clear that many of the foundational papers use "ropelength". I would say the "10 times more common" claim is in favor of "ropelength". Since I cannot move pages yet, I will ask an admin to do so. --Horoball 02:04, 28 September 2007 (UTC)
The failure to include this information is abusive to the reader
[edit]- [Where L the length and L(L) is what???? Or where L is the knot and L(L) is the rope length of the knot?]
Michael Hardy (talk) 23:07, 6 July 2010 (UTC)
- I agree that the notation here was really bad. I rewrote it to the best of my understanding but checking by someone more expert in the subject would be a good idea. —David Eppstein (talk) 00:58, 7 July 2010 (UTC)
Minimal rope length?
[edit]The article says 12 times as long as the thickness is too short to tie a knot. What's the minimal necessary length? And why doesn't the article either answer that question or say that nobody knows? Michael Hardy (talk) 23:08, 6 July 2010 (UTC)
New upper bounds and possible mistake
[edit]There are now better upper bounds for the ropelength of the trefoil knot, for example in Przybyl and Pieranski, High resolution portrait of the ideal trefoil knot, J. Phys. A: Math. Theor. (47) , 2014. I would gladly update it myself, but there is a factor 2 issue that I do not really understand: the bound in the aforementioned paper is 32.7429345. It looks to me that the bounds around 16 are for the ratio Length/Diameter instead of Length/Radius, but I am confused by the definition of Thickness here on Wikipedia which is somehow less intuitive, and for which there is also a factor 2 difference with the one in the paper "Quadrisecants give new lower bounds for the ropelength of a knot" for example. So actually it seems to me that with the definition that we use, the ropelength of the trefoil should be around 32 instead of 16, but I am afraid to correct it myself as I do not master this topic (in particular, the question would actually be more relevant with a 2 foot rope). Could anyone clarify this or tell me that I am wrong? Ventricule (talk) 15:50, 23 October 2014 (UTC)