I should prove that the teardop $S^2(p)$ (the orbifold with underlying surface $S^2$ and a single cone point of order $p>1$) and the spindle $S^2(p,q)$ (the orbifold with underlying surface $S^2$ and two cone points of orders $p,q>1$, $p\neq q$) are bad orbifolds, that is they are not orbifold covered by any surface. I worked out the teardrop case using an argument involving the Euler characteristic, but the same idea fails with the spindle. I guess I should find a geometric proof for the spindle, but I tried without any success. Could you help me with that? Thank you.
The teardrop and the spindle are bad orbifolds
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low-dimensional-topology
orbifolds