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Dec 28, 2020 at 22:09 answer added Mark Bell timeline score: 4
Mar 3, 2020 at 21:31 history edited YCor
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Mar 3, 2020 at 19:02 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
Nov 4, 2019 at 19:01 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
Oct 5, 2019 at 18:16 answer added Ryan Budney timeline score: 3
Oct 5, 2019 at 17:57 comment added Just Me Thanks @RyanBudney, I'll take a look. You seem to make a few mental leaps which I'll have to climb... if you'd like to turn your comments into an answer, I'd gladly accept it.
Oct 5, 2019 at 16:18 comment added Ryan Budney Mark Bell's "Flipper" appears to be an all-in-one implementation of my initial suggestion, finding the JSJ decomposition of the mapping torus -- although I doubt he uses Regina. flipper.readthedocs.io His software appears well-written. I had looked at some of his software many years ago. These packages appear complete now.
Oct 5, 2019 at 16:12 comment added Ryan Budney I can imagine a relatively "expensive" way to do it in Regina, looking for incompressible tori in the mapping torus. Have you tried the Bell-Webb algorithm? I have not, but here is an implementation: curver.readthedocs.io/en/master It sounds like it might be exactly what you want, although the authors seem to imply this implementation can be slow, or perhaps memory-intensive.
Oct 4, 2019 at 19:06 history edited Just Me
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Oct 4, 2019 at 18:42 history edited Just Me CC BY-SA 4.0
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Oct 4, 2019 at 18:36 history edited Just Me CC BY-SA 4.0
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Oct 4, 2019 at 18:33 comment added Just Me @RyanBudney Thanks for the correction. Do you have a reference giving some kind of algorithm for determining whether an element lies in the image of this map?
Oct 4, 2019 at 17:37 comment added Ryan Budney Your homomorphism of braid groups, you would either need to make those pure braid groups, or make the $n_i's$ all equal and turn it into a wreath product construction. Regardless, this is the $\pi_1$ map for the $2$-cubes operad's multiplication map. It's discussed in many books and papers that talk about operads, as the cubes operad is perhaps the most heavily studied object in the subject.
Oct 4, 2019 at 15:17 history edited Just Me CC BY-SA 4.0
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Oct 4, 2019 at 15:08 history asked Just Me CC BY-SA 4.0