New posts in homology-cohomology

What does this map $\mathbb{R}P^\infty\to\mathbb{C}P^\infty$ induce on cohomology?

$f_*$ induces an isomorphism in homology iff the mapping cone of $f_*$ is contractible.

Natural equivalence between singular and simplicial homology

What is the true relationship between impossible figures and cohomology?

Square differential forms in cohomology

Universal coefficient theorem with ring coefficients

Calculate the cohomology group of $U(n)$ by spectral sequence.

Homology of a simplicial set

Proof of $H^k(X,\mathbf k) = H^k(X,\mathbb Z) \otimes \mathbf k$

Are maps inducing the same cohomology homomorphisms homotopic?

Cohomology of Grassmannian

Homology and Fundamental group of $\mathbb{R}^4\setminus S^1$

Finding a space with given homology groups and fundamental group

Cohomology of complex projective plane

$G$-equivariant quasi-ismorphisms over a field

Tensors as matrices vs. Tensors as multi-linear maps

Can $H_1(\partial \lvert \mathcal R \rvert ) \to H_1(\lvert \mathcal R \rvert)$ be non injective?

Homology group of $X=\operatorname{SL}(2,\mathbb{R})/\operatorname{SL}(2,\mathbb{Z})$

Homology and cohomology of 7-manifold

$\pi_1$ and $H_1$ of Symmetric Product of surfaces