§9 · Salvage 1 · Leading coefficients · 2026-10-18T06:50:14Z

Theorem S1.5 · Theorem 8.0.2 over \(\mathbb F_q((t))\) for symmetric \(X\): the complete hypothesis list

proved correction ★ key step

Correction. Corrects Theorem 1.9 · Theorem 8.0.2 over \(\mathbb F_q((t))\), \(p\) odd, symmetric \(X\): hypotheses, Objection 5.20 · Audit of A1-9: the characteristic-p Theorem 8.0.2 and its hypotheses.

The direct characteristic-\(p\) form of Theorem 8.0.2 for symmetric \(X\) holds under the hypotheses of Theorem 1.9 plus H1H1 · Sakellaridis's triangularity (7.5) for the actual Θ of X. Equivalent to (U): the virtual colours belonging to each simple spherical root sum to its coroot (S1-1). in the form (U)(U) · For every simple spherical root γ, the virtual colours belonging to γ sum to its coroot: one copy of the coroot for type G, one pair for type T. Equivalent to (7.5) (S1-1). (one colour set per simple spherical root, equivalent to (7.5)), H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit. (adapted data over \(F\)) and H3H3 · No spherical root of type N. (no type \(N\)). The non-vanishing of \(c\) and of every leading coefficient \(a_J\) is a consequence, by positivity, and not a fourth hypothesis. The \(E_6/F_4\) corollary is unchanged.

Theorem S1.5.

Theorem. Let \(F=\mathbb F_q((t))\) with \(p\) odd, \(G\) as in (A1)(A1) Field and group: F a non-archimedean local field of characteristic 0 (Sakellaridis §1.1), G split reductive over O with connected fibres and simply connected derived group (§1.7)., \(\theta\) an involution of \(G\) over \(O\), \(X=G/G^\theta\), \(x_0=eG^\theta\). Let \(W_X'=N_W(\mathfrak a)\cap[W/W_L]\) act on \(\Lambda_X\), with closed antidominant chamber \(C^-\), \(\Lambda_X^-=\Lambda_X\cap C^-\), and \(A_X^+\) the points of \(A_X(F)\) with label in \(\Lambda_X^-\). Let \(\Theta\), \(\Theta^+\) and the types be as in Sakellaridis §§6.3, 7.1, read over an algebraic closure of \(F\). Assume:

Then there is a canonical isomorphism \(C_c^\infty(X(F))^K\cong\mathbb C[\delta(X)^{1/2}A_X^*]^{W_X'}\). Under it \(f\in\mathcal H_K\) acts as multiplication by \(r(\mathcal Sf)\), and \(\mathbf 1_{x_0K}\mapsto1\). Hence (SG) \(\iff\) \(r\) is onto. No hypothesis on the leading coefficients is needed: \(c\neq0\) and \(a_J\neq0\) for all \(J\) follow from the others (Lemma S1.3). Axiom 2.2.1Sakellaridis's Axiom 2.2.1, relabelled (A3a): rank-one models over O. ((A3a)(A3a) Rank-one models over O (Sakellaridis's Axiom 2.2.1): for every Borel orbit Y of maximal rank and every simple root α, the O-scheme YP_α/R(P_α) is one of the four standard PGL2-spaces over O, with his scheme structure on Y, and YP_α is the closure of its generic fibre minus the closure of the generic boundary.) and '\(L_\gamma\) classical' ((A4)(A4) Spherical roots and colours: no pair of maximal rank of type N; classical Levis L_γ; Statements 6.3.1 and 7.1.5.(ii)) are not used. 'No type \(N\)' ((A4)(A4) Spherical roots and colours: no pair of maximal rank of type N; classical Levis L_γ; Statements 6.3.1 and 7.1.5.(i)) is used, as H3H3 · No spherical root of type N..

Corollary (\(\mathcal M_\theta\), unchanged). For \(X=\mathcal M_\theta\) (\(E_6/F_4\)) the hypotheses H1H1 · Sakellaridis's triangularity (7.5) for the actual Θ of X. Equivalent to (U): the virtual colours belonging to each simple spherical root sum to its coroot (S1-1)., H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit., H3H3 · No spherical root of type N., (E) and (A4)(A4) Spherical roots and colours: no pair of maximal rank of type N; classical Levis L_γ; Statements 6.3.1 and 7.1.5.(iv)\(_p\) hold or are not needed: \(\Theta^+=\check\Phi_X^+\) with multiplicity one, both simple roots of type \(G\), adapted data explicit (S4-11), and \(\beta\) built directly (Computation 1.7). Also \(a_J\in\{1,1+t,c\}\) explicitly (Proposition S1.2(b)). So the theorem holds modulo (A2)(A2) Integral model: X quasi-affine over O, its open Borel orbit smooth and surjective over O with B-homogeneous special fibre; a G-eigenmeasure on X and a B-invariant measure on the open orbit (§1.7)., (A3b′), (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x. and \((\mathrm{S6.3.1})_p\), as in Theorem 1.9 and Objection 5.20.

Proof sketch. Each line names the step that proves it.

  1. Invariants and local structure (\(P(X)\), \(L(X)\), \(A_X\), \(\Lambda_X\), \(\delta(X)\); smooth \(H\) and \(B_y\)): Lemma 1.3, over \(\bar F\), characteristic \(\neq2\). Finitely many \(B(F)\)-orbits, only \(\mu_2\)-torsion: Lemma 1.4, with H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit..
  2. Open-orbit functionals \(S_\chi\), \(\chi\in D'=\delta(X)^{-1/2}A_X^*\): convergence, generic uniqueness, rationality: Proposition 1.5, with H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit..
  3. Functional equations and the sum formula (6.2) over \(W_X'\): Proposition 1.6, using (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x. and the invariant measure.
  4. Coboundary. For \(\gamma\in\Delta_X\), Sakellaridis's computation (p. 61) gives \(\beta/(\beta\circ w_\gamma)=-e^{\check\gamma}\prod_{\theta\in D_\gamma}\frac{1-\sigma_\theta q^{-r_\theta}e^{-\check\theta}}{1-\sigma_\theta q^{-r_\theta}e^{\check\theta}}\). Here \(D_\gamma=N_\Theta(w_\gamma)\) by (A4)(A4) Spherical roots and colours: no pair of maximal rank of type N; classical Levis L_γ; Statements 6.3.1 and 7.1.5.(iv)\(_p\), and \(w_\gamma\) permutes \(\Theta^+\smallsetminus D_\gamma\). H3H3 · No spherical root of type N. gives every simple root a formula in Statement 6.3.1. (U)(U) · For every simple spherical root γ, the virtual colours belonging to γ sum to its coroot: one copy of the coroot for type G, one pair for type T. Equivalent to (7.5) (S1-1). makes the product exactly the factor of (6.3)–(6.5), so (A4)(A4) Spherical roots and colours: no pair of maximal rank of type N; classical Levis L_γ; Statements 6.3.1 and 7.1.5.(iii)\(_p\) gives \(B_{w_\gamma}=\beta/(\beta\circ w_\gamma)\); this is the step that review G1 found to rest on Lemma 7.1.4. Both sides are cocycles of the same type (Audit 5.15(c)), so \(B_w=\beta/(\beta\circ w)\) for all \(w\in W_X'\), and symmetrizing gives (7.4).
  5. Triangularity. By Lemma S1.1, (7.5) holds with \(\mathcal T=\operatorname{cone}(\Theta^+)\). By Proposition S1.2(a), the weights of \(\Pi_\lambda\) lie in \(\lambda+\mathcal T\) and \(\Pi_0=c\); the latter uses (E). Here \(\mathcal T\) is strictly convex (it lies in the colour cone), \(\mathcal R\subseteq\mathcal T\), and \(\mathcal T\cap C^-=\{0\}\) by (E).
  6. Non-vanishing. \(c\neq0\) and \(a_J/c>0\) for every antidominant \(\lambda\): Lemma S1.3, using (A2)(A2) Integral model: X quasi-affine over O, its open Borel orbit smooth and surjective over O with B-homogeneous special fibre; a G-eigenmeasure on X and a B-invariant measure on the open orbit (§1.7)., (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x., steps 2–5 and the adjunction.
  7. Last step. Apply Proposition 1.2 with \(\mathcal T\) as in 5: (a) is (A3b′); (b) is step 2; (c) follows from 5–6 through the adjunction and the substitution \(\iota(\psi)=w_L\psi^{-1}\) (Proposition 1.2 Remark (i), Audit 5.16), with leading index \(\sigma\lambda=-w_0^X\lambda\) and cone \(-w_0^X\mathcal T\), which still meets \(C^-\) only in $0$. \(P_0=1\) gives \(\mathbf 1_{x_0K}\mapsto1\).
  8. (SG). \(\mathcal H_K*\mathbf 1_{x_0K}\) maps to \(r(\mathbb C[A^*]^W)\cdot1\), so (SG) \(\iff\) \(r\) onto (Objection 5.20 step 5).

What changed against Theorem 1.9. (i) The general list gains (U)(U) · For every simple spherical root γ, the virtual colours belonging to γ sum to its coroot: one copy of the coroot for type G, one pair for type T. Equivalent to (7.5) (S1-1)., H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit. and H3H3 · No spherical root of type N., as in Objection 5.20. (U)(U) · For every simple spherical root γ, the virtual colours belonging to γ sum to its coroot: one copy of the coroot for type G, one pair for type T. Equivalent to (7.5) (S1-1). replaces the shape condition 'multiplicity-free \(\Theta^+\subseteq\check\Phi_X^+\)'. (ii) (7.5) is proved by Lemma S1.1, not by the inversion-set argument of Computation 1.7. (iii) '\(c\neq0\) by Lemma 4.2.3' is replaced by Lemma S1.3(iii). (iv) The leading coefficients are no longer an unproved input. (v) Review G6 says H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit. should follow from (A2)(A2) Integral model: X quasi-affine over O, its open Borel orbit smooth and surjective over O with B-homogeneous special fibre; a G-eigenmeasure on X and a B-invariant measure on the open orbit (§1.7). by \(H^1(\mathbb Z/2,U''(F))=0\); this is not checked here, so H2H2 · F-rational adapted data: a θ-stable split maximal torus T ⊆ B over F containing a maximal θ-split torus, with B adapted and x0 in the open Borel orbit. stays a hypothesis. (vi) Characteristic 0 is the same statement with \(F/\mathbb Q_p\); there (U)(U) · For every simple spherical root γ, the virtual colours belonging to γ sum to its coroot: one copy of the coroot for type G, one pair for type T. Equivalent to (7.5) (S1-1). is Lemma 7.1.4 (Remark S1.4).

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  • Summary S1.6 · Verdict inputs A5-20 and A5-21 re-derived; how R-4(b) and its open items read
  • Re-check V1 · Re-check by G1
  • Summary 7.5 · Verdict after the audit: unchanged for \(E_6/F_4\); the general direct form completed

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