Generic admissible-cut coproduct on ConnesKreimer R (Nonplanar α) #
The three MCB coproducts — Δ^ρ (pruning), Δ^c (contraction/trace), Δ^d
(deletion) — share one shape: a primitive ofTree T ⊗ 1 plus a sum over cut
summands (crown, trunk) of of' crown ⊗ ofTree trunk. They differ only
in the cut enumeration cuts T. This file factors that shape into a single
cuts-parameterized algebra hom comulAlgHomNG; the concrete coproducts are
its instantiations — Δ^ρ at cuts := cutSummandsN
(Coproduct/Pruning.lean) and Δ^c at cuts := cutSummandsCN τ
(Coproduct/Trace.lean, definitionally).
The cut-enumeration layer was already generic (ConnesKreimer.cutSummandsG,
over an extraction policy); this lifts that genericity to the coproduct
operator, so one Merge operator (Minimalist.Merge.mergeOpG, downstream)
serves every coproduct instead of one bespoke copy per Δ.
Main definitions #
comulTreeNG cuts/comulForestNG cuts— the generic coproduct.comulAlgHomNG cuts— packaged as anAlgHom.comulTreeNG_eq_sum/comulForestNG_eq_sum— the coproduct as a single sum over the cut convolutionstreeCutsG/forestCutsG(Combinatorics/RootedTree/Cut.lean).WithCuts R cuts— the policy-indexed carrier, withBialgebragated onIsAdmissibleCuts cuts.
The generic admissible-cut coproduct (tree level), parameterized by a cut
enumeration cuts. Specializing cuts to cutSummandsN gives Δ^ρ, to
cutSummandsCN τ gives Δ^c, to the deletion enumeration gives Δ^d.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Forest-level generic coproduct (multiplicative extension).
Equations
- ConnesKreimer.comulForestNG cuts F = (Multiset.map (ConnesKreimer.comulTreeNG cuts) F).prod
Instances For
Forest-level generic coproduct as a MonoidHom on the additive forest monoid.
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- One or more equations did not get rendered due to their size.
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The generic admissible-cut coproduct as an algebra hom, parameterized by
the cut enumeration cuts.
Equations
Instances For
The generic coproduct as a sum over cut convolutions #
treeCutsG/forestCutsG (Combinatorics/RootedTree/Cut.lean) enumerate
the (crown, trunk-forest) pairs of a tree and their convolution over a
forest; cutTensor sends a pair to of' crown ⊗ of' trunk. These
single-sum expansions serve the Δ^ρ cocycle substrate
(Coproduct/Pruning.lean) and the Δ^c double-cut coassoc proof
(Coproduct/Trace.lean).
Tensor-product factor of a (crown, trunk) cut pair.
Equations
- ConnesKreimer.cutTensor p = ConnesKreimer.of' p.1 ⊗ₜ[R] ConnesKreimer.of' p.2
Instances For
cutTensor is multiplicative over the cut convolution combinerProjG.
comulTreeNG as a single multiset sum over treeCutsG.
comulForestNG as a single multiset sum over forestCutsG.
The policy-indexed carrier WithCuts #
The WithLp pattern: a type synonym indexed by the cut policy, whose
Bialgebra instance is gated on an admissibility mixin. Δ^ρ keeps the plain
carrier (instBialgebraRho, the Hopf algebra of
[MCB25] Lemma 1.2.11); the marked variants live here.
Type synonym for ConnesKreimer R (Nonplanar α) carrying the generic
admissible-cut coproduct at the fixed policy cuts.
Equations
- ConnesKreimer.WithCuts R cuts = ConnesKreimer R (RoseTree.Nonplanar α)
Instances For
Equations
- One or more equations did not get rendered due to their size.
Equations
- ConnesKreimer.instAlgebraWithCuts cuts = { smul := ConnesKreimer.instAlgebraWithCuts._aux_1 cuts, algebraMap := ConnesKreimer.instAlgebraWithCuts._aux_3 cuts, commutes' := ⋯, smul_def' := ⋯ }
Admissibility of a cut policy: the generic coproduct comulAlgHomNG cuts is
coassociative and counital, uniformly in the coefficient ring. Gates the
Bialgebra instance on WithCuts (the Fact-style mixin of the WithLp
pattern).
- coassoc (R : Type u_3) [CommRing R] [CharZero R] [NoZeroDivisors R] : (↑(Algebra.TensorProduct.assoc R R R (ConnesKreimer R (RoseTree.Nonplanar α)) (ConnesKreimer R (RoseTree.Nonplanar α)) (ConnesKreimer R (RoseTree.Nonplanar α)))).comp ((Algebra.TensorProduct.map (comulAlgHomNG cuts) (AlgHom.id R (ConnesKreimer R (RoseTree.Nonplanar α)))).comp (comulAlgHomNG cuts)) = (Algebra.TensorProduct.map (AlgHom.id R (ConnesKreimer R (RoseTree.Nonplanar α))) (comulAlgHomNG cuts)).comp (comulAlgHomNG cuts)
- counit_rTensor (R : Type u_4) [CommSemiring R] : (Algebra.TensorProduct.map counit (AlgHom.id R (ConnesKreimer R (RoseTree.Nonplanar α)))).comp (comulAlgHomNG cuts) = ↑(Algebra.TensorProduct.lid R (ConnesKreimer R (RoseTree.Nonplanar α))).symm
- counit_lTensor (R : Type u_5) [CommSemiring R] : (Algebra.TensorProduct.map (AlgHom.id R (ConnesKreimer R (RoseTree.Nonplanar α))) counit).comp (comulAlgHomNG cuts) = ↑(Algebra.TensorProduct.rid R R (ConnesKreimer R (RoseTree.Nonplanar α))).symm
Instances
The generic admissible-cut bialgebra on the marked carrier: any admissible
policy yields Bialgebra R (WithCuts R cuts). Δ^c is recovered at
cuts := cutSummandsCN τ.
Equations
- ConnesKreimer.WithCuts.instBialgebra cuts = Bialgebra.ofAlgHom (ConnesKreimer.comulAlgHomNG cuts) ConnesKreimer.counit ⋯ ⋯ ⋯