What quotients can I take of $\mathbb{R}^{3}$ that give me $\mathbb{R}^{3}$ back?
Thankyou
What quotients can I take of $\mathbb{R}^{3}$ that give me $\mathbb{R}^{3}$ back?
Thankyou
If you take $\mathbb{R}^{3}/\mathbb{D}^{3}$, then you get $\mathbb{R}^{3}$ back as a topological space. The same applies to an arbitary disjoint union of $\mathbb{D}^{3}$s, since you can deform all of them in the same time to a point.