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Diff — Covering space

Revision #1133 → #2282 · back to history

addedConnected covering is surjective with constant fiber cardinalityfa5805191d98
modifiedFactorisation of coverings (first)85b18570aaa1
FieldFrom #1133To #2282
noteNo composition lemma for `IsCoveringMap` exists; grep for `IsCoveringMap.comp` returns nothing.No composition lemma for `IsCoveringMap` exists; `IsCoveringMap.comp` is absent.
modifiedBranched covering of degree naad1f1a52dc8
FieldFrom #1133To #2282
noteNot formalized as branched covering, though `isCoveringMapOn_npow` covers the unramified locus.Not formalized as branched covering, though `isCoveringMap_npow` covers the unramified locus.
addedUniversal cover unique up to equivalencecc8798d7c7de
addedSO(3) is RP³ with Spin(3) = S³ as universal covera024ebef25c2