§3 · Agent 3 · Hypotheses in char p · 2026-10-18T03:02:13Z

Summary 3.12 · (Q3) verdict: (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).–(A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x., (A5)(A5) X homogeneous and affine, and the open Borel orbit has a single B(F)-orbit of F-points (§8)., (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,ii,iv) hold over \(\mathbb F_q((t))\)

proved audit: correct ★ key step

Second audit: correct. Each row of the verdict table matches a node I re-derived: (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)., (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). Proposition 3.2; (A3b)(A3b) Cartan decomposition (Sakellaridis's Axiom 2.4.1): the X-antidominant torus points represent every K-orbit on X(F), and points with distinct labels lie in distinct K-orbits. Lemma 3.3, Proposition 3.4, Audit 3.5, Theorem 3.8; (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x. Audit 3.9; (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), (ii), (iv) and the combinatorics of (iii) Proposition 3.6, Proposition 3.7, Proposition 3.10, with one-line repairs in Proposition 3.6 and Proposition 3.7 (Audit 5.10, Objection 5.11); (A5)(A5) X homogeneous and affine, and the open Borel orbit has a single B(F)-orbit of F-points (§8). Lemma 3.3. The only open item is the analytic part of Statement 6.3.1 (Remark 3.11), and the invariants listed are those computed. The checklist claims are true: Theorem 8.0.2 in characteristic p is never used; all stabilizers are smooth; H^1 is taken only of smooth connected groups; p = 3 needs no change (the Weyl modules used are minuscule for E6 or the D5 vector representation, irreducible for p odd). The consequence for (SG) is correctly stated as conditional on (Q1) and (Q2). The proofs also apply to p-adic F, because DS and BT III cover it.

For \(p\) odd and \(\mathcal M_\theta=(G_{\mathbb Z}/G_{\mathbb Z}^{\theta_0})\otimes\mathbb F_q[[t]]\), every hypothesis of Sakellaridis's Theorem 8.0.2 assigned to (Q3) is proved by characteristic-\(p\) arguments, except Statement 6.3.1, whose combinatorial input is verified and whose analytic part belongs to (Q1). The same proofs work for \(p\)-adic \(F\), \(p\) odd, and remove from S4/S4b the citations of Kneser, Vust/Richardson, Helminck–Wang, Alper, Knop and Helgason.

Summary 3.12.

Table 2. hypothesis and for \(\mathcal M_\theta\) over \(\mathbb F_q(\!(t)\!)\), \(p\) odd and status
hypothesisfor \(\mathcal M_\theta\) over \(\mathbb F_q(\!(t)\!)\), \(p\) oddstatusnodes
(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).\(G\) split reductive over \(\mathcal O\), connected fibres, simply connected derived groupprovedProposition 3.2
(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).\(X\) smooth quasi-affine; \(\mathring X=U_P\times A_X\) smooth, surjective, \(B\)-homogeneous special fibre; invariant forms; \(X(\mathcal O)=Kx_0\)provedProposition 3.2
(A3b)(A3b) Cartan decomposition (Sakellaridis's Axiom 2.4.1): the X-antidominant torus points represent every K-orbit on X(F), and points with distinct labels lie in distinct K-orbits.\(X(F)=\bigsqcup_{\kappa\in\Lambda_S^+}Kx_\kappa\), \(X(F)/K\simeq\Lambda_X^+\) via \(A_X^+\)proved (Bruhat–Tits III cited)Lemma 3.3, Proposition 3.4, Audit 3.5, Theorem 3.8
(A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x.\(Jx\subseteq B(\mathcal O)x\) for \(x\in A_X^+\)provedAudit 3.9
(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)maximal-rank pairs only of types \(G,U\)provedProposition 3.6
(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)\(L_{\gamma_1},L_{\gamma_6}\) of type \(D_5\)provedProposition 3.7
(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)Statement 6.3.1combinatorics proved; analytic part open (Q1)Proposition 3.10, Remark 3.11
(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)Statement 7.1.5provedProposition 3.10
(A5)(A5) X homogeneous and affine, and the open Borel orbit has a single B(F)-orbit of F-points (§8).\(X_F\) homogeneous affine, \(\mathring X(F)\) one \(B(F)\)-orbitprovedLemma 3.3

Invariants in characteristic \(p\ne2\): \(\mathcal X(X)=\mathbb Z\omega_1\oplus\mathbb Z\omega_6\); \(\Lambda_X^+=\Lambda_X\cap\{\langle v,\gamma_1\rangle\le0,\langle v,\gamma_6\rangle\le0\}\); \(\Delta_X=\{\gamma_1,\gamma_6\}\), type \(G\); colours \(D_1,D_6\) with valuations \(\check\gamma_1,\check\gamma_6\); \(W_X\simeq S_3\); 45 maximal-rank orbits; \(\Theta=\check\Phi_X\times\{(+,4)\}\).

  1. (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)., (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). (Proposition 3.2): Conrad's Lemma 2.2.4 and Thm 2.3.1, valid over any base, replace Edixhoven and Alper; connectedness of the fibres is proved directly.
  2. (A5)(A5) X homogeneous and affine, and the open Borel orbit has a single B(F)-orbit of F-points (§8). (Lemma 3.3).
  3. (A3b)(A3b) Cartan decomposition (Sakellaridis's Axiom 2.4.1): the X-antidominant torus points represent every K-orbit on X(F), and points with distinct labels lie in distinct K-orbits.: \(G(F)=KT(F)H(F)\) by Delorme–Sécherre, whose field hypothesis includes \(\mathbb F_q(\!(t)\!)\) and whose proof was checked (Audit 3.5); one \(H(F)\)-class of maximal \((\theta,F)\)-split tori by a direct argument (Proposition 3.4) using Bruhat–Tits III instead of Kneser; labels through \(\mathcal V\) (Proposition 3.7) and \(W_X\subseteq K\) (Theorem 3.8).
  4. (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x. (Audit 3.9). (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. (Proposition 3.6, Proposition 3.7, Proposition 3.10); remaining: Remark 3.11.
  5. Consequence, stated but not claimed. If (Q1) supplies Theorem 8.0.2 over \(\mathbb F_q(\!(t)\!)\) under (A1)–(A5)Sakellaridis's standing assumptions for Theorem 8.0.2: (A1) characteristic-0 field and split group; (A2) integral model; (A3a) rank-one models over O, (A3b) Cartan decomposition, (A3c) Iwahori orbits (his Axioms 2.2.1, 2.4.1, 2.4.2); (A4) spherical roots and colours; (A5) homogeneous, affine, one open Borel orbit. (including the analytic part of Statement 6.3.1) and (Q2) supplies (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. for \(\mathcal M_\theta\) over \(\mathbb F_q[[t]]\), then Proposition VII (\(r\) not onto, every \(q\)) gives that (SG) fails for \(E_6/F_4\) over \(\mathbb F_q(\!(t)\!)\). No hypothesis is verified here by appeal to Theorem 8.0.2 in characteristic \(p\) (checklist item 10).
  6. Checklist. (1) Each characteristic-0 citation is replaced or shown characteristic-free (Audit 3.1). (2) The arguments use \(2\in\mathcal O^\times\) and separability of \(F(\sqrt t)\), never \(\mathrm{char}\,F=0\). (3) Integral statements are proved as statements about \(\mathcal O\)-schemes (open immersions, purity, torsors), not fibrewise. (5) All stabilizers are smooth. (6) Only \(H^1\) of \(\mathrm{Spin}_8\), \(F_4\), split tori and split unipotent groups is used. (8) The dictionary \(\Lambda_X^+\leftrightarrow\Lambda_S^+\) is explicit (Theorem 3.8 step 1). (9) No 'almost every place'. (11) \(p=3\) needs no change (Audit 3.1 step 2).

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