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Jan 30, 2021 at 18:41 answer added Ian Agol timeline score: 4
Dec 23, 2020 at 16:22 comment added HJRW @dodd -- presumably you are worried about the compact case with boundary, rather than the non-compact case addressed in YCor's comment. Compact 3-manifolds with boundary are retracts of their doubles, which are closed. This usually makes it easy to reduce from the compact case to the closed case.
Dec 20, 2020 at 19:11 comment added Ian Agol A uniform treatment of the word problem in 3-manifold groups is given here: arxiv.org/abs/1609.06253 However, the issues of computational complexity are not addressed.
Dec 20, 2020 at 16:48 review Suggested edits
Dec 20, 2020 at 18:58
Dec 19, 2020 at 3:29 vote accept Ben Cooper
Dec 19, 2020 at 3:29 comment added Ben Cooper I've tried to make the statement at the end more precise
Dec 19, 2020 at 3:28 history edited Ben Cooper CC BY-SA 4.0
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Dec 19, 2020 at 0:49 answer added Moishe Kohan timeline score: 11
Dec 18, 2020 at 21:57 comment added markvs So what is the answer?
Dec 18, 2020 at 21:56 comment added YCor @dodd using infinite connected sums it's easy to product non-closed 3-manifold groups that are not computable.
Dec 18, 2020 at 21:50 history edited YCor
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Dec 18, 2020 at 19:55 comment added markvs Is the 3-manifold closed?
Dec 18, 2020 at 19:04 comment added YCor I don't understand the last paragraph: there should be a quantifier for $l$.
Dec 18, 2020 at 19:02 comment added YCor In SOL the Dehn function is exponential but the word problem is very efficiently solvable. The assertion, sometimes heard, that the Dehn function is a measure of the complexity of the word problem is quite misleading. Actually, I'd tend to believe that the $\pi_1$ of every compact 3-fold (possibly with boundary) embeds into a group with quadratic Dehn function (but I don't think this is the easiest/ most efficient approach to algorithms).
Dec 18, 2020 at 17:02 comment added Moishe Kohan If you restrict to irreducible 3-manifolds then "most" have automatic fundamental groups (the only exceptions are Sol and Nil-manifolds). This gives you some "explicit" bounds. See "Word processing in groups."
Dec 18, 2020 at 16:47 history asked Ben Cooper CC BY-SA 4.0