All Questions
4 questions
5
votes
1
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318
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Irreducible 3-manifold with boundary of genus greater than 1
Let $M$ be an irreducible 3-manifold with incompressible boundary of genus > 1.
When is $M$ homotopy equivalent to an Eilenberg-MacLane space? Or it is never true?
1
vote
0
answers
137
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Covers of a 4-manifold pull back a cohomology class to any algebraic multiple
Fix an algebraic integer $x\neq 0$. Is there a closed smooth 4-manifold $M$ with a class $\rho\in H^{1}_{\mathrm {dR} }(M)$ and a smooth covering map $\phi:M\to M$ such that $\phi^*\rho=x\rho$?
Is ...
2
votes
1
answer
372
views
isotopy classes of embeddings of the torus
Let's consider $S^1$-bundle $E$ over a 2-manifold $M$. How many isotopy classes of embeddings of the torus $\mathbb{T}^2$ in $E$?
For each free homotopy classes $\gamma$ of mappings of the circle ...
4
votes
2
answers
472
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Does a homeomorphism of $S^1 \times S^2$ which is homotopy to the identity has to isotope to it?
I guess the question can be asked for all manifolds. But I am particularly interested in $S^1 \times S^2$ right now. Concrete example preferrd.