Prove that $S^2$ is symplectic manifold
45187
Symplectic form on 2-sphere?
14652
Proof a $(2n-1)$-compact manifold
62950
Use implicit function theorem to show $O(n)$ is a manifold
132653
How to show that $\mathfrak{sl}_n(\mathbb{R})$ and $\mathfrak{sl}_n(\mathbb{C})$ are simple?
151735
$\mathbb{R}^3 \setminus A$ deformation retracts onto $S^1 \vee S^2$
130045
Show that $l^2$ is a Hilbert space
154990
Fundamental group of two tori with a circle ($S^1✕${$x_0$}) identified
118622
Local diffeomorphism from $\mathbb R^2$ onto $S^2$
64993
Connectedness of the $S^2$ sphere
119579
$S^2 \times S^2$ is diffeomophic to $G_2(\mathbb{R}^4)$
80100
Boundary of product manifolds such as $S^2 \times \mathbb R$
36137
Prove $GL_2(\mathbb{Z}/2\mathbb{Z})$ is isomorphic to $S_3$
122352
Topologies in a Riemannian Manifold
68014
Prove that $\mathfrak{su}(2)$ is not isomorphic to $\mathfrak{sl}(2,\mathbb R)$
27629
How to prove that $S^{2n+1}/S^1$ is homeomorphic to $\mathbb CP^n$ under a given identification
45276
Continuous map on $S^2$
68234
Is $[0,1) \cup \{2\}$ a manifold with boundary? My issue is the $2$.