§5 · Agent 5 · Audit: transfer, hypotheses · 2026-10-18T04:34:18Z
Objection 5.20 · Audit of A1-9: the characteristic-p Theorem 8.0.2 and its hypotheses
proved audit: error ★ key step
Used later by: Summary 5.21 · Verdict of the second audit: A1-1 … A1-9 (direct rerun over F_q((t))), Theorem 7.4 · Verdict: Sakellaridis's theorem over \(\mathbb F_q(\!(t)\!)\); for \(E_6/F_4\) in both characteristics, (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. included.
Corrected by: Lemma S1.1 · (7.5) for every \(\Theta\): 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). is equivalent to one colour set per simple root, Lemma S1.3 · Positivity of \(\hat S\) forces \(c\neq0\) and \(a_J/c>0\) over every local field, Theorem S1.5 · Theorem 8.0.2 over \(\mathbb F_q((t))\) for symmetric \(X\): the complete hypothesis list, Summary S1.6 · Verdict inputs A5-20 and A5-21 re-derived; how R-4(b) and its open items read.
For \(\mathcal M_\theta\) the theorem and corollary of Theorem 1.9 are correct: everything reduces to \((\mathrm{S6.3.1})_p\), which by Audit 5.19 follows from \((I_\Lambda)\). For a general symmetric \(X\) the stated list of hypotheses is incomplete. The proof also uses the inequality (7.5) for a general \(\Theta\) (Sakellaridis's own argument for it is wrong by a factor 2, and A1's fix covers only multiplicity-free \(\Theta^+\subseteq\check\Phi_X^+\)), the \(F\)-rationality of the adapted data, and the absence of type-\(N\) roots.
Objection 5.20.
Outcome: the \(\mathcal M_\theta\) corollary holds. The general theorem needs hypothesis H = 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..
- 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). (triangularity). For every \(w\in W_X'\) and \(I\subseteq\Theta^+\), \(\check\rho-w\check\rho+w|I|\in\mathcal T\) for a cone \(\mathcal T\supseteq\mathcal R\) with \(\mathcal T\cap C^-=\{0\}\). Sakellaridis derives (7.5) from \(|\Theta^+|-w|\Theta^+|=\check\rho-w\check\rho\), which is false whenever \(\Theta^+=\check\Phi_X^+\) with multiplicity one: the left side is \(2(\check\rho-w\check\rho)\). A1's inversion-set argument proves 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). exactly when \(\Theta^+\subseteq\check\Phi_X^+\) without repetitions. If some \(\check\gamma\) occurs twice, 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). fails: in rank one, \(\Theta^+=\{\check\gamma,\check\gamma\}\) and \(I=\Theta^+\) give \(s_{2\check\gamma}=-(e^{-\check\gamma}+1+e^{\check\gamma})\), a weight below \(0\). Other shapes (e.g. half-coroots in type \(T\)) need a separate check. So 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). is an additional hypothesis, or must be proved case by case.
- 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. (rational data). There is a \(\theta\)-stable split maximal torus \(T\subseteq B\) containing a maximal \(\theta\)-split torus \(S\) (maximal over \(\bar F\)), with \(B\) adapted and \(x_0=eH\in\mathring X\). Lemma 1.3 works over \(\bar F\), and Lemma 1.4, Proposition 1.5 use these data over \(F\). They 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 choosing a \(\theta_{x_0}\)-stable maximal \(F\)-torus of \(B\cap\theta_{x_0}B\), but no node proves this.
- H3H3 · No spherical root of type N. (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.(iii)\(_p\): Statement 6.3.1 for a set of reflections generating \(W_X'\)" presupposes that every simple spherical root has type \(G\), \(T\) or \((U,\psi)\): Statement 6.3.1 gives no formula for type \(N\). So "no type \(N\)" is used implicitly, contrary to the claim that (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 not used.
Minor. Step 2's "\(c\neq0\) by Lemma 4.2.3, whose proof needs only the invariant measure" misdescribes the lemma (it uses (4.5)); \(c\neq0\) follows from \(\Omega_\chi\not\equiv0\) (Audit 5.15 step 7).
- What the proof uses, step by step. Lemma 1.3, Lemma 1.4, Proposition 1.5 hold 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. and the cited characteristic-\(\ne2\) inputs (Springer's finiteness of \(B_{\bar F}\)-orbits, Steinberg 7.5, CGP 2.1.10, BZ, Bernstein's principle): Audit 5.14, Audit 5.18. Proposition 1.6 holds with (A3c)(A3c) Iwahori orbits (Sakellaridis's Axiom 2.4.2): xJ ⊆ xB(O) for every X-antidominant torus point x. and the invariant measure (Audit 5.15). The passage to (7.4) needs Statements 6.3.1 and 7.1.5 in characteristic \(p\) (so H3H3 · No spherical root of type N.) and 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).. Proposition 1.2 needs (A3b′), triangularity (H1 plus the cone condition (E)) and non-zero leading coefficients (Audit 5.16, Audit 5.17).
- Why (E) suffices once 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). holds. Under Statement 7.1.5, each simple coroot lies in \(\operatorname{cone}(\Theta^+)\): it is the virtual colour of a type-\(G\) root, or the sum of the two colour valuations of a type-\(T\) root. So \(\mathcal R\subseteq\operatorname{cone}(\Theta^+)\), and (E) is the condition \(\mathcal T\cap C^-=\{0\}\) for \(\mathcal T=\operatorname{cone}(\Theta^+)\).
- The counterexample to multiplicity two. In rank one with \(\check\rho=\check\gamma/2\): \(s_\nu=\big(e^{\nu}-e^{\check\gamma-\nu}\big)/(1-e^{\check\gamma})\). Then \(s_{2\check\gamma}=(e^{2\check\gamma}-e^{-\check\gamma})/(1-e^{\check\gamma})=-(e^{-\check\gamma}+1+e^{\check\gamma})\). Its weight \(-\check\gamma\) violates "all weights in \(0+\mathcal R\)". It contributes to \(\prod_{\Theta^+}(1-q^{-r}T)s_0\) unless cancelled. So the shape of \(\Theta\) matters, and the printed argument cannot be cited.
- \(\mathcal M_\theta\) corollary. \(\Theta^+=\check\Phi_X^+\) is multiplicity-free, and Computation 1.7 does not need Statement 7.1.5 at all (it builds \(\beta\) from \(\check\Phi_X^+\)). 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. is explicit (S4-11). The only simple spherical roots are \(\gamma_1,\gamma_6\), of type \(G\) (A3-6, A3-7). So the hypotheses reduce to (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., \((\mathrm{S6.3.1})_p\). The first three hold over \(\mathbb F_q(\!(t)\!)\): A3-2, Theorem 3.8 or Proposition 4.5 read with antidominant labels, and Audit 3.9 (with the repairs of Audit 5.10, Objection 5.11, which do not touch these items). \((\mathrm{S6.3.1})_p\) follows from \((I_\Lambda)\) (Audit 5.19). Then Proposition VII (\(r\) not onto, every \(q\)) gives the failure of (SG) over \(\mathbb F_q(\!(t)\!)\).
- (SG) \(\iff\) \(r\) onto. Under the isomorphism with \(\mathbf 1_{x_0K}\mapsto1\), \(\mathcal H_K*\mathbf 1_{x_0K}\mapsto r(\mathbb C[A^*]^W)\). This is correct and insensitive to \(f\mapsto f^\vee\) (Audit 5.16).
- What A1-9 achieves for (Q1). A characteristic-\(p\) proof of the analytic half of Theorem 8.0.2 for symmetric \(X\), with characteristic-\(\ne2\) inputs only. For \(\mathcal M_\theta\) the whole theorem holds modulo the single generating-function identity \(Z_F=R_q\) (Dead end 1.8(i)). That identity is a point-count statement over \(\mathbb F_q[t]/t^N\) by Dead end 1.8(ii). It is implied by \((I_\Lambda)\), and it might also be attacked directly, without \((I_\Lambda)\).
Builds on
- Theorem 1.9 · Theorem 8.0.2 over \(\mathbb F_q((t))\), \(p\) odd, symmetric \(X\): hypotheses
Built on by
- Summary 5.21 · Verdict of the second audit: A1-1 … A1-9 (direct rerun over F_q((t)))
- Lemma S1.1 · (7.5) for every \(\Theta\): 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). is equivalent to one colour set per simple root
- Theorem S1.5 · Theorem 8.0.2 over \(\mathbb F_q((t))\) for symmetric \(X\): the complete hypothesis list
- Summary S1.6 · Verdict inputs A5-20 and A5-21 re-derived; how R-4(b) and its open items read
- Review G6 · Review G6 · Agent 5
- Theorem 7.4 · Verdict: Sakellaridis's theorem over \(\mathbb F_q(\!(t)\!)\); for \(E_6/F_4\) in both characteristics, (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. included
Sources
- Theorem 1.9 (claim audited)
- sakellaridis-v3.pdf: Statement 6.3.1 pp. 44–45; §7.1 pp. 58–60; Thm 7.2.1, proof and (7.5) pp. 60–62; Lemma 4.2.3 p. 27
- props/e6-f4-module.html (Proposition VII)
- nodes Audit 5.14 … Audit 5.19