The smooth ambient-isotopy equivalence relation #
This file defines smooth ambient isotopy for arbitrary bundled smooth maps between real manifolds. Two maps are smoothly ambient isotopic when the final diffeomorphism of a diffeotopy of the codomain carries the first map to the second.
The relation is defined generally before its specialization to bundled smooth embeddings in
TauCeti.Geometry.Manifold.SmoothEmbedding.SmoothAmbientIsotopy.Basic, following the
GeometricTopology roadmap's encoding convention. Forgetting smoothness recovers
TauCeti.AmbientIsotopic.
Main definitions #
TauCeti.SmoothAmbientIsotopic: smooth ambient isotopy of arbitrary bundled smooth maps.TauCeti.SmoothAmbientIsotopic.setoid: the resulting equivalence relation.
Main results #
TauCeti.SmoothAmbientIsotopic.refl,symm, andtrans: smooth ambient isotopy is an equivalence relation.TauCeti.SmoothAmbientIsotopic.final_comp: a map is smoothly ambient isotopic to its postcomposition with the time-one map of a diffeotopy.TauCeti.SmoothAmbientIsotopic.precomp: smooth ambient isotopy is preserved by precomposing both maps with a fixed smooth map.TauCeti.SmoothAmbientIsotopic.ambientIsotopic: smooth ambient isotopy implies continuous ambient isotopy.
References #
- G. Burde and H. Zieschang, Knots, 2nd ed., de Gruyter (2003), Chapter 1, for ambient isotopy of knots.
- M. Hirsch, Differential Topology, Springer GTM 33 (1976), Chapter 8, §8.1, for smooth isotopies and diffeotopies.
Two bundled smooth maps are smoothly ambient isotopic when the final diffeomorphism of a
C^n diffeotopy of the codomain carries the first map to the second.
Equations
- TauCeti.SmoothAmbientIsotopic f g = ∃ (Φ : TauCeti.Diffeotopy J' n N), (↑Φ.final).comp f = g
Instances For
Smooth ambient isotopy is witnessed by a diffeotopy whose final diffeomorphism postcomposes the first smooth map to the second.
A diffeotopy carrying f to g witnesses their smooth ambient isotopy.
Transport along a diffeotopy is an ambient isotopy. A smooth map and its postcomposition with the time-one map of a diffeotopy of the codomain are smoothly ambient isotopic: the diffeotopy itself is the witness.
Smooth ambient isotopy of smooth maps is reflexive.
Smooth ambient isotopy of smooth maps is symmetric.
Smooth ambient isotopy of smooth maps is transitive.
Precomposing two smoothly ambient-isotopic maps with the same smooth map preserves the relation: the witnessing diffeotopy of the codomain is unchanged.
Smooth ambient isotopy implies continuous ambient isotopy after forgetting smoothness.
Smooth ambient isotopy is an equivalence relation on bundled smooth maps.
The smooth-ambient-isotopy equivalence relation on bundled smooth maps.
Equations
- TauCeti.SmoothAmbientIsotopic.setoid J J' n M N = { r := TauCeti.SmoothAmbientIsotopic, iseqv := ⋯ }
Instances For
The relation of the smooth-ambient-isotopy setoid is smooth ambient isotopy.