Transport of the circles of a smoothed PD-code #
The circles of a smoothed PD-code (TauCeti.PDCode.ResolvedCircle) are built from half-edge
labels, so two codes describing the same smoothed diagram have different, but canonically
bijective, circle types. The Khovanov chain groups are tensor products indexed by these circles,
so every comparison of diagrams has to carry such a bijection along, functorially.
A TauCeti.PDCode.SmoothingEquiv D s D' s' is a bijection of half-edges carrying the arcs of D
to the arcs of D' and the traversal of D smoothed by s to the traversal of D' smoothed by
s', together with a bijection between the labels of the crossing-free circles. It induces a
bijection of resolved circles, TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr, sending the
circle through a half-edge to the circle through its image. Smoothing equivalences form a
groupoid, and the induced bijections respect identities, inverses and composition.
Transport carrying the slots of a crossing bijectively preserves the circles through that crossing and hence their number. When the source and target transports of a saddle use the same half-edge and isolated-circle bijections, the induced circle bijections commute with its saddle correspondence. This supplies the circle-level naturality square for resolution maps.
The smoothing equivalences provided here are those of the native operations which keep the smoothed diagram:
- relabelling half-edges and crossings (
TauCeti.PDCode.relabel), where the state is read at the old crossing names; - mirroring (
TauCeti.PDCode.mirror), which exchanges theA- andB-smoothings and so negates the state; - reading a crossing from another slot (
TauCeti.PDCode.rotateCrossing); - permuting the labels of the crossing-free circles.
A TauCeti.PDCode.ResolutionEquiv D D' identifies all smoothings of D with those of D' at
once, along a bijection of crossings, by one half-edge bijection and one bijection of crossing-free
labels. It gives a smoothing equivalence for every state, and so transports the whole cube of
resolutions. Relabelling, reading a crossing from another slot and permuting the crossing-free
labels are such identifications.
Finally, the circles of a disjoint union (TauCeti.PDCode.disjointUnion) are the circles of the
two summands, smoothed by the two restrictions of the state
(TauCeti.PDCode.disjointUnionResolvedCircleEquiv).
Main definitions #
TauCeti.PDCode.SmoothingEquiv: an isomorphism of smoothed PD-codes.TauCeti.PDCode.SmoothingEquiv.crossingCircleCongr,TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr: the induced bijections of circles.TauCeti.PDCode.SmoothingEquiv.relabel,TauCeti.PDCode.SmoothingEquiv.mirror,TauCeti.PDCode.SmoothingEquiv.rotateCrossing,TauCeti.PDCode.SmoothingEquiv.crossinglessPerm: the smoothing equivalences of the native operations.TauCeti.PDCode.ResolutionEquiv: an identification of all smoothings of two codes, with its smoothing equivalencesTauCeti.PDCode.ResolutionEquiv.smoothingEquivand the instancesTauCeti.PDCode.ResolutionEquiv.relabel,TauCeti.PDCode.ResolutionEquiv.rotateCrossingandTauCeti.PDCode.ResolutionEquiv.crossinglessPerm.TauCeti.PDCode.disjointUnionResolvedCircleEquiv: the circles of a disjoint union.
Main results #
TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr_refl,TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr_symm,TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr_trans: the identity, inverse and composition laws.TauCeti.PDCode.SmoothingEquiv.image_crossingCircleCongr_circlesAt,TauCeti.PDCode.SmoothingEquiv.card_circlesAt_eq: transport carrying the slots of a crossing bijectively carries the circles through it, and so their number.TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr_saddleResolvedCircleMap: induced circle bijections commute with saddle correspondences.TauCeti.PDCode.eqvGen_circleStep_disjointUnion_iff: two half-edges of a disjoint union lie on one circle exactly when they do so within one summand.
References #
- M. Khovanov, A categorification of the Jones polynomial, Duke Math. J. 101 (2000), 359-426, §2 (the circles of a resolution).
An isomorphism between the PD-code D smoothed according to the state s and the PD-code
D' smoothed according to s': a bijection of half-edges carrying the arc matching of D to
that of D' and the smoothed traversal TauCeti.PDCode.statePerm D s to D'.statePerm s',
together with a bijection between the labels of the crossing-free circles. It induces a bijection
between the circles of the two smoothed diagrams
(TauCeti.PDCode.SmoothingEquiv.resolvedCircleCongr).
The bijection of half-edges.
The bijection between the labels of the crossing-free circles.
- edgePair_apply (x : Fin (4 * n)) : ↑D'.edgePair (self.halfEdgeEquiv x) = self.halfEdgeEquiv (↑D.edgePair x)
The half-edge bijection carries the arc matching of
Dto that ofD'. - statePerm_apply (x : Fin (4 * n)) : (D'.statePerm s') (self.halfEdgeEquiv x) = self.halfEdgeEquiv ((D.statePerm s) x)
The half-edge bijection carries the smoothed traversal of
Dto that ofD'.
Instances For
The groupoid of smoothing equivalences #
The identity smoothing equivalence.
Instances For
The identity smoothing equivalence is the identity on half-edges.
The identity smoothing equivalence is the identity on crossing-free labels.
The inverse of a smoothing equivalence.
Instances For
The inverse smoothing equivalence inverts the half-edge bijection.
The inverse smoothing equivalence inverts the bijection of crossing-free labels.
The composite of two smoothing equivalences.
Instances For
A composite smoothing equivalence composes the half-edge bijections.
A composite smoothing equivalence composes the bijections of crossing-free labels.
Composition of smoothing equivalences is associative.
The induced bijection of circles #
A smoothing equivalence transports the native arc matching by conjugation.
A smoothing equivalence transports the smoothed traversal.
Two half-edges lie on one circle of the smoothed D' exactly when their preimages under a
smoothing equivalence lie on one circle of the smoothed D.
The bijection between the circles meeting a crossing induced by a smoothing equivalence: the circle through a half-edge goes to the circle through its image.
Instances For
The bijection of circles induced by a smoothing equivalence: the circle through a half-edge goes to the circle through its image, and the crossing-free circles are matched by the bijection of their labels.
Instances For
On the circles meeting a crossing, the induced bijection is
TauCeti.PDCode.SmoothingEquiv.crossingCircleCongr.
On the crossing-free circles, the induced bijection is the bijection of their labels.
The identity smoothing equivalence induces the identity on the circles meeting a crossing.
The inverse smoothing equivalence induces the inverse bijection of circles meeting a crossing.
A composite of smoothing equivalences induces the composite bijection of circles meeting a crossing.
The identity law: the identity smoothing equivalence induces the identity on circles.
The inverse law: the inverse smoothing equivalence induces the inverse bijection of circles.
The composition law: a composite of smoothing equivalences induces the composite bijection of circles.
Transport of the circles through a crossing and of saddle correspondences #
A smoothing equivalence carrying the slots of c bijectively to those of c' carries
exactly the circles through c to those through c'. The slot bijection permits a different
choice of the first slot at the crossing.
The number of circles through a crossing is preserved when its slots are transported bijectively by a smoothing equivalence. In particular, the merge/split conditions transport.
Saddle correspondences commute with smoothing equivalences that use the same half-edge and isolated-circle bijections at the two endpoints. Every unaffected circle is retained.
The smoothing equivalences of the native operations #
Relabelling the half-edges along half and the crossings along cross is a smoothing
equivalence from D smoothed by t ∘ cross to the relabelled code smoothed by t: the state is
read at the old crossing names. The crossing-free circles keep their labels.
Instances For
Mirroring exchanges the A- and B-smoothings, so it is a smoothing equivalence from D
smoothed by a state t to the mirror smoothed by the complementary state s, which is the
identity on half-edges.
Instances For
Reading a crossing from another slot does not change the smoothed diagram: it is a smoothing equivalence which is the identity on half-edges.
Instances For
Permuting the labels of the crossing-free circles is a smoothing equivalence of every smoothed code to itself, which is the identity on half-edges.
Instances For
Permuting the crossing-free labels is the identity on half-edges.
Permuting the crossing-free labels by σ acts on them by σ.
Transport of all smoothings at once #
An identification of all the smoothings of D with those of D' along a bijection of
crossings: a bijection of half-edges carrying the arcs of D to those of D', such that for
every state t of D' it carries the traversal of D smoothed by t ∘ crossingEquiv to the
traversal of D' smoothed by t, together with a bijection between the labels of the
crossing-free circles. It then carries the slots of each crossing c bijectively to those of
crossingEquiv c (TauCeti.PDCode.ResolutionEquiv.exists_slots). Each state gives a
smoothing equivalence (TauCeti.PDCode.ResolutionEquiv.smoothingEquiv), all with the same
half-edge and isolated-circle bijections, so these transports commute with every saddle of the
cube of resolutions.
Relabelling (TauCeti.PDCode.ResolutionEquiv.relabel), reading a crossing from another slot
(TauCeti.PDCode.ResolutionEquiv.rotateCrossing) and permuting the crossing-free labels
(TauCeti.PDCode.ResolutionEquiv.crossinglessPerm) are such identifications. Mirroring is not:
it exchanges the A- and B-smoothings.
The bijection of crossings.
The bijection of half-edges.
The bijection between the labels of the crossing-free circles.
- edgePair_apply (x : Fin (4 * n)) : ↑D'.edgePair (self.halfEdgeEquiv x) = self.halfEdgeEquiv (↑D.edgePair x)
The half-edge bijection carries the arc matching of
Dto that ofD'. - statePerm_apply (t : Fin m → Bool) (x : Fin (4 * n)) : (D'.statePerm t) (self.halfEdgeEquiv x) = self.halfEdgeEquiv ((D.statePerm (t ∘ ⇑self.crossingEquiv)) x)
The half-edge bijection carries the traversal of
Dsmoothed byt ∘ crossingEquivto the traversal ofD'smoothed byt.
Instances For
The half-edge bijection carries the four half-edges of c bijectively onto those of
crossingEquiv c, by a slot bijection Fin 4 ≃ Fin 4.
Two identifications of all smoothings with the same half-edge and crossing-free bijections
are equal: the crossing bijection is determined by the half-edge bijection, since
crossingEquiv c is the crossing of the image of any slot of c.
The smoothing equivalence of an identification of all smoothings, from D smoothed by s to
D' smoothed by a state t which agrees with s along the crossing bijection.
Instances For
The smoothing equivalences of an identification of all smoothings share its half-edge bijection.
The smoothing equivalences of an identification of all smoothings share its bijection of crossing-free labels.
The identity identification of the smoothings of D.
Instances For
The identity identification is the identity on crossings.
The identity identification is the identity on half-edges.
The identity identification is the identity on crossing-free labels.
The identity identification gives the identity smoothing equivalences.
The inverse of an identification of all smoothings.
Instances For
The inverse identification inverts the crossing bijection.
The inverse identification inverts the half-edge bijection.
The inverse identification inverts the bijection of crossing-free labels.
The smoothing equivalences of the inverse identification are the inverses of the smoothing equivalences.
The composite of two identifications of all smoothings.
Instances For
The crossing bijection of a composite is the composite of the crossing bijections.
The half-edge bijection of a composite is the composite of the half-edge bijections.
The bijection of crossing-free labels of a composite is the composite of these bijections.
The smoothing equivalences of a composite are the composites of the smoothing equivalences.
Inverting an identification of all smoothings twice gives it back.
An identification of all smoothings followed by its inverse is the identity.
The inverse of an identification of all smoothings followed by it is the identity.
Equal codes have the same smoothings: the identification along an equality of codes is the identity on crossings, half-edges and crossing-free labels.
Instances For
The identification along an equality of codes is the identity on crossings.
The identification along an equality of codes is the identity on half-edges.
The identification along an equality of codes keeps the crossing-free labels.
Relabelling the half-edges along half and the crossings along cross identifies the
smoothings of D with those of the relabelled code. The crossing-free circles keep their
labels.
Instances For
Relabelling is a smoothing equivalence of every state; it is
TauCeti.PDCode.SmoothingEquiv.relabel.
Reading a crossing from another slot keeps every smoothing: it identifies the smoothings
of D with those of the rotated code, by the identity on crossings and half-edges.
Instances For
Reading a crossing from another slot is the identity on crossings.
Reading a crossing from another slot is the identity on half-edges.
Reading a crossing from another slot keeps the labels of the crossing-free circles.
Reading a crossing from another slot is a smoothing equivalence of every state; it is
TauCeti.PDCode.SmoothingEquiv.rotateCrossing.
Permuting the labels of the crossing-free circles identifies the smoothings of D with
themselves, by the identity on crossings and half-edges.
Instances For
Permuting the crossing-free labels is the identity on crossings.
Permuting the crossing-free labels is the identity on half-edges.
Permuting the crossing-free labels acts on them by σ.
Permuting the crossing-free labels is a smoothing equivalence of every state; it is
TauCeti.PDCode.SmoothingEquiv.crossinglessPerm.
The circles of a disjoint union #
Two half-edges of a disjoint union lie on one circle exactly when they come from the same summand and lie on one circle of that summand, smoothed by the restricted state.
The circles meeting a crossing of a smoothed disjoint union are those of the two summands, smoothed by the two restrictions of the state.
Instances For
A circle through a half-edge of the first summand is a circle of the first summand.
A circle through a half-edge of the second summand is a circle of the second summand.
The circles of a smoothed disjoint union are the circles of the two summands, smoothed by the two restrictions of the state. The circle through a half-edge of a summand is the circle through it in that summand, and the crossing-free circles of the first summand are numbered before those of the second.
Instances For
The crossing-free circles of the first summand are numbered first in the disjoint union.
The crossing-free circles of the second summand are numbered after those of the first in the disjoint union.