The (136) R-stage for Γ = G_ℚ₂ #
Discharges the per-source residues of blockStageR136 (GQ2/BlockRStage.lean) at the local
source Γ = AbsGalQ2, per the route of record (docs/orchestration/p16d6a-handoff.md §3): one
prop_5_16-package invocation per twisted module, through its standalone pieces —
hcard—#H²(G_ℚ₂, 𝔽₂) = 2=card_H2_zmod2_eq_two(clause (iii));hZcount—#RCocycle = z_R = #R²·#D_R: the crossed-cocycle group isZ¹(G_ℚ₂, R_{f₀})(multiplicative↔additive bridge, the Prop. 8.9 assemblyTCocyclepattern), counted bycard_Z1_eq(clause (ii)), with#fixedPts C (R^∨) = #D_Rvia theY-invariance bridge (fixedPtsEquivRChar) +blockRChar_card;hsep_hom— the(R^∨)^C-separation:obs g = 0forces every invariant character to kill the paired defect class (obs_zero_iff_pairClass_zero), the paired classes are thecup20-values of theR-valued defect class,bijective_cup20_dualEval(clause (vi)) forces[rDefect] = 0inH²(G_ℚ₂, R_ρ),B²-extraction produces the continuous splitting cochain, andhomLift_of_splitassembles the lift.
The twisted action throughout is the C = Y/K-conjugation on R (well-defined by
lemma_7_2's K-centrality, threaded as hRK), pulled back along the surjective lower map
of the boundary lift (BoundaryLifts bundles surjectivity — this is why hsep_hom is
supplied directly to blockStageR136 rather than through hsep_hom_of_splitCriterion, whose
hsplit quantifies over arbitrary, possibly non-surjective g).
The lemma_7_2 outputs (hRK = R central in K, hR2 = R exponent 2) and hfg
(t.f.g. of G_ℚ₂ — B1, reserved for the §9 induction) thread hypothesis-side to the assembly.
Axioms here: std-3 + B6 + B7 (through card_Z1_eq/card_H2_zmod2_eq_two/
bijective_cup20_dualEval).
Main result: stageR136_local — the (136) identity for the block frame at the local
source, the exact stageR136 field of the RecursionInputs bundle (the Prop. 8.9 assembly).
K ◁ Y as an instance (the MinimalBlock field, made searchable).
The C = Y/K conjugation action on R (well-defined by K-centrality) #
R is abelian: it is central in K (hRK, from lemma_7_2) and contained in K.
Equations
- GQ2.RStageLocal.rCommGroup Blk hRK = { toGroup := inferInstance, mul_comm := ⋯ }
Instances For
Conjugation on R by an element of Y depends only on its K-coset (K-centrality).
Conjugation by y lands back in R (R ◁ Y).
The C = Y/K conjugation action on Additive R (Quotient.out-conjugation; independent
of the representative by conj_eq_of_mk_eq_K).
Equations
- One or more equations did not get rendered due to their size.
Instances For
The action computed at any coset representative.
Shared C = Y/K-module helpers (used by hZcount and hsep_hom) #
hZcount: the z_R torsor count at the local source #
The z_R torsor count, local source (the Prop. 8.9 assembly residue): for every boundary lift f₀,
#RCocycle = z_R = #R² · #D_R. Route: RCocycle ≃ Z¹(G_ℚ₂, R_{f₀}) (multiplicative crossed ↔
additive, the conjugation action through C = Y/K pulled back along the surjective
mk' K ∘ f₀), card_Z1_eq (5.16 clause (ii), B6+B7), and the invariant-character bridge
fixedPts C (R^∨) ≃ D_Rmod + blockRChar_card.
hsep_hom: the (R^∨)^C separation at the local source #
The G_ℚ₂-action on 𝔽₂ is trivial (any group action on ZMod 2 fixes both elements).
The (R^∨)^C-separation, local source (the Prop. 8.9 assembly residue): if the obstruction functional
of a boundary lift g vanishes, g lifts to a continuous homomorphism into Y. Route:
obs g = 0 kills every paired defect class (obs_zero_iff_pairClass_zero); the paired classes
are the cup20-values of the R-valued defect class against the invariant characters, and
H⁰(G_ℚ₂, R^∨) = (R^∨)^C = D_Rmod by surjectivity of the lower map; bijective_cup20_dualEval
(5.16 clause (vi), B6) then forces [rDefect] = 0 in H²(G_ℚ₂, R_ρ); B²-extraction yields a
continuous splitting cochain (exponent 2 kills the signs), and homLift_of_split assembles the
lift.
The assembly, parametric over hsep_hom #
(136) for the block frame at the local source, parametric over hsep_hom
(the Prop. 8.9 assembly residue assembly): htriv/hcard/hZcount are discharged
(htriv_local/card_H2_zmod2_eq_two/hZcount_local); the remaining inputs are the
lemma_7_2 structural facts (hRK/hR2), hfg (B1, reserved for the §9 induction), and
hsep_hom — the (R^∨)^C-separation (next increment: prop_5_16 clause (vi) +
B²-extraction + homLift_of_split; see the module docstring for the surjectivity
scoping note).
(136) for the block frame at the local source — all residues discharged
(the Prop. 8.9 assembly): htriv/hcard/hZcount/hsep_hom are all proved; the remaining hypotheses are
the lemma_7_2 structural facts (hRK/hR2) and hfg (B1, reserved for the §9 induction). The
conclusion is the stageR136 field of the local RecursionInputs bundle, verbatim.