# 490d Mirror checkpoint after C273

24 September 2026. Latest completed step: **C273 — the 529 dependency synthesis through C272**. Existing research continues; no restart.

## Main conclusion

C266–C272 form a connected source-qualified comparison with explicit dependencies. The 17K source paths, local placement, regular SP register and retained 13K chains are distinct inputs to the construction. Several later equalities express the same conditions and must not be counted as independent witnesses.

The strongest unresolved question is **whether the chronology independently requires the declared placement and calibration conditions**. Selected closing-source connectivity is established; the large affine charts remain different operations from those source translations.

## Compact dependency account

| Stage | Retained result |
|---|---|
| Cumulative placement | MT/LXX Flood 5290, Shem 5888; SP Flood 4715, Shem 5313 |
| Local reflection | Source 600 minus translation increment 598 gives H=F−2 and J1(x)=2−x |
| Central geometry | 5+1+1+5+1+1=14; selected SP/LXX/MT radii 5/6/7 |
| Closing 17K rectangle | Shem −5883→SP Flood 3110; Flood −5283→SP Noah 3710; both 8993 |
| Induced regular maps | RN(y)=y−3703; RF(y)=3105−y; 3703=17K−10K=7K |
| Finite regular register | j=2g+1−c; rho=2g−c; six same-Gear primary/start or companion/close matches among 36 |
| Outer local bracket | Radii 23/4 and 25/4, displayed 5750/6250 at 1000:1 |
| Separate 13K chain input | Widths 6877→7475→8125 at anchors −4419/−4417 |
| Calibrated charts | Phi_s,a=a+s(x−1) ; s=1196/1300; sourced 299 midpoints, generated 325 midpoints |
| C272 finite result | 72 image instances ; 10 hits representing 8 inherited targets, all at rho=6 ; 62 generated |

The chronology/source identities, derived coordinate locations, source-path support and chart images remain separately typed.

## Conditional determination of the translations

Let f be the MT Flood translation, h=f+598 the Shem translation. The declared MT closing join gives

\[
f-5289=5889-(f+598),
\]

so f=5290=10K, h=5888 and the shared center is 1. The common MT/LXX Flood shift places LXX at [0,7]. Requiring SP Flood to be the global reflection of MT Flood places it at [−1,6], determining 4715 and then 5313.

These values are unique **conditional on the joining premises**. This does not independently establish that the chronology requires those premises. The source 598 interval and its assignment as a translation increment remain distinct claims.

## Dependencies and limits that must survive restart

The outer conditions (4rho+1)/(4rho−1)=25/23, the chart endpoint gap 104(rho−6)=0 and rho=6 express the same algebra under the held charts. Those charts were calibrated to the outer bracket. Their inherited successes are not independent confirmations.

The 17K closing source route from C254 is −5283→−4415→1404→2460→3710, with widths 868+5819+1056+1250. Its prefix is 6875; it does not establish missing exact 13K target 2462. The frozen graph has the Shem closing node/edge but not Flood closing node −5283; later source support does not amend that graph.

C271 covers cumulative indices 2–7, six boundaries spanning five elapsed years. Indices 0/1 require regular records absent from the held register. Opposite-role local co-location does not fill those gaps. All six input ancestries remain supported even when their C272 outputs are generated.

The C268/C272 charts act on cumulative source q as a+s(q+5289), anchored at −5289. They miss the actual 868 attachment targets by 2392/2600 for N02 and 4784/5200 for N04. They do not implement those source translations. Unit-magnitude maps preserve half-year spacing; charts turn it into 598/650 and compare images as target pair centers.

Sourced midpoints 2757/2759 remain SP companion Noah deaths; generated midpoints 3381/3383 remain without target records in the held register. No new event identification is licensed by the synthesis.

Marker roles remain: 2500 generated midpoint;5000/6000/7000 selected center radii;5750/6250 seasonal components;7500 whole-envelope length. Center span 14, seasonal-envelope sum 15 and union 14.5 remain different quantities. Preserve the complementary Year 14/Year 15 readings. No common historical event path for every macro radius or z-law is established.

## Evidence and controls

43 frozen immediate inputs; C265→C272 report/result certificate chain verified; **156 targeted C273 checks**; six generated outputs replayed byte identically. No historical campaign rerun or new numerical search. Eighteen claim groups organize dependencies; they are not proved independent or formally minimal. The authored assessment is not a machine-proved theorem.

C273 review is an author consistency review. Earlier independent reviews remain earlier work; no new independent-agent review is claimed.

File_18 SHA-256: `68301ab760bfbe2e874aedc5c8d943ced7a6219d34bc2859332a70713f9630d5`.

File_09 SHA-256: `45851004c5864229ebf6a896f9099819a08d8926715d3e97e4bc3985c4a3876e`.

C127 graph and C265 certificate unchanged. Keep K=529, E=25/23, P=70/69 and rho=radius. Global Mirror remains January AD 1; local junction x=1 remains January AD 2; no civil year zero. Regular Gears remain Noah/Shem/Flood only. SP person companions and Flood event closes remain distinct. Capture now, canonize later; no canonical changes, cumulative/upstream Gear, primer reopening or new axis.

Original unprefixed Reports 01–10 and interrupted, unestablished original Reports 11–25 remain distinct from the C-series. The superseded AD 1905–1911 lookup remains unexecuted.

## Best next bounded step

**C274:** hold source coordinates, phase convention and the 598 translation increment fixed. Remove one placement premise at a time: MT closing join; common MT/LXX Flood shift; SP/MT global interval reflection. Solve the remaining affine constraints and record which translations, radii and symmetries remain determined or become free. Do not refit free values to restore matches or add source events. **High is sufficient. C274 is proposed, not executed.**

Publish completed reports and incremental evidence as work proceeds; await Dean’s next instruction.