New posts in geometric-topology

$\{(x,y)\!\in\!\mathbb{B}^n; -\varepsilon\leq-\|x\|^2\!+\!\|y\|^2\leq\varepsilon\}\approx\mathbb{B}^k\!\times\!\mathbb{B}^{n-k}$

general-topology algebraic-topology differential-geometry differential-topology geometric-topology

If $\int_{0}^{1}f=\int_{0}^{1}g=1$, then there exists an interval $I \subset [0,1]$ such that $\int_{I}f=\int_{I} g =\frac{1}{2}$

general-topology geometric-topology

Two disjoint real projective planes in real projective space?

general-topology geometric-topology projective-space

Fundamental group of the total space of an oriented $S^1$ fiber bundle over $T^2$

algebraic-topology geometric-topology fundamental-groups fiber-bundles low-dimensional-topology

What is this manifold?

geometry algebraic-topology manifolds geometric-topology

Cover of the disk that behaves like a circle

general-topology algebraic-topology geometric-topology

Do oriented null cobordant manifolds admit spin structures?

differential-geometry algebraic-topology differential-topology geometric-topology spin-geometry

Criteria of a trivial G bundle of a 3-manifold

general-topology differential-geometry differential-topology geometric-topology fiber-bundles

Example of contractible open manifold that is not $\mathbb{R}^n$ - varieties?

algebraic-geometry algebraic-topology geometric-topology

When are maps between topological manifolds automatically surjective?

algebraic-topology geometric-topology

Covering points on a sphere with a disk

geometry general-topology geometric-topology tiling

Is Seifert-Weber space homogeneous for a Lie group?

manifolds lie-groups geometric-topology homogeneous-spaces

Nontrivial h-cobordism

differential-topology geometric-topology

Reference on manifolds with corners

differential-geometry reference-request manifolds differential-topology geometric-topology

Understanding Poincare Duality

algebraic-topology differential-topology geometric-topology duality-theorems

A quadratic reciprocity formula

number-theory geometric-topology

Equivalence of definitions of $S^\infty$

general-topology geometric-topology

Explicit calculus of Hilbert-Smith conjecture

group-actions geometric-topology low-dimensional-topology

Covering spaces of $S^1 \vee S^1$.

abstract-algebra general-topology algebraic-topology geometric-topology fundamental-groups

Does the fundamental group detect the unlink?

general-topology differential-topology geometric-topology fundamental-groups knot-theory