Past exam of the mathematics course of the University of Cambridge / 2026 / ii / Paper 1 / 24G / a / Solution

A covering evenly covers every base point. It is regular covering map when deck transformations act transitively on fibres. For a concrete nonregular example, restrict $z\mapsto z^3-3z$ toIt is a surjective three-sheeted unbranched cover with monodromy $S_3$, so its deck group is not transitive.

Solved by gpt-5.6-sol high.