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Jan
26
awarded  Necromancer
Dec
14
answered Unique factorization of manifolds?
Dec
6
awarded  Enlightened
Dec
6
awarded  Nice Answer
Nov
28
awarded  Nice Answer
Nov
28
comment spin structures on knot complements
Compute the co-homology group you're interested via excision, relating the pair $(M,\partial M)$ to $(S^3, K)$. I've voted to migrate to MSE.
Nov
6
comment triviality of vector bundles with the reduced homology of base space entirely torsion
This looks a little homework-ish. What is motivating this question for you?
Oct
19
comment Poincare Duality Reference
That article is commenting on an irrellevant side-issue. They're talking about the dual cell decomposition when it is applied to a non-PL triangulation. This means there's no requirement for the triangulation to be compatible with a global PL structure on the manifold. This is a fairly "exotic" idea. Usually when people talk about triangulated manifolds, they're triangulated PL manifolds. So in this article the link of a cell (from the triangulation) need not be a triangulated (standard) sphere.
Oct
7
reviewed Leave Open Mathematical Difference between “there is one” and “there is EXACTLY one”
Oct
7
reviewed Close limit of square root of x whether one or does not exist
Oct
7
reviewed Leave Open Order infinite or finite
Sep
21
comment Can $S^2$ be homeomorphic to a simplicial complex with fewer than 3 two-simplices?
Finding the minimal triangulations of $S^2$, $S^1 \times S^1$ and higher genus surfaces are fun homework problems in many intro algebraic topology courses... Have you looked to see how they do this in some textbooks?
Sep
21
comment Every triangulation on a disk is orientable.
If your disk has a moebius band, it has a one-sided circle. So you need something like the Jordan Curve Theorem. Homology + Poincare duality would suffice, as well. Anything of that form.
Sep
13
comment the variation of the measure under a quasisymmeric homeomorphism
What does "quasisymmetric" mean?
Sep
4
comment What's the derivative of a map defined on manifolds?
@astudent: then it's time to read about the tangent bundle.
Sep
1
comment Tool for the partition problem with planar rectangles
Thanks Joseph. Hmm, I suspect the most efficient process will be to make scaled-down versions out of paper and shuffle them around to see if I can pack them onto a scaled version of the big sheet. :( Because I'm a slow coder...
Sep
1
asked Tool for the partition problem with planar rectangles
Aug
5
comment Text book for sheaf theory
Have you tried typing "Sheaf theory" into a search at a book retailer?
Aug
4
awarded  Yearling
Aug
1
awarded  reference-request