{"id": "c796", "title": "C796 — Explain the BJ fifty-year contraction by its two components", "filename": "C796.md", "role": "Research action", "step": 796, "sha256": "e3837fd68aa636fbc21294b70a6d141dd32c75057ddacba10fd00e9d1e8dd87a", "bytes": 1169, "origins": ["C480–C1634/Research_Cycles/C0732_C0831/journal.json#C796"], "download": "/sources/e3837fd68aa636fbc21294b70a6d141dd32c75057ddacba10fd00e9d1e8dd87a.md", "format": "md", "derived": true, "tags": [], "excerpt": "Why does removing57 appear as2450→2400?", "content": "# C796 — Explain the BJ fifty-year contraction by its two components\n\n## Question\n\nWhy does removing57 appear as2450→2400?\n\n## Inputs\n\n```json\n{}\n```\n\n## Sources\n\n```json\n[\n  \"File53 §3A; literal trunk roles\"\n]\n```\n\n## Opened utc\n\n2026-09-28T02:06:05.299719+00:00\n\n## Results\n\n```json\n{\n  \"spans\": {\n    \"Creation_to_Conquest\": 2450,\n    \"Fall_to_rest\": 2450,\n    \"compressed_Creation_to_rest\": 2400,\n    \"compressed_Fall_to_rest_diagnostic\": 2393,\n    \"compressed_Creation_to_Conquest_diagnostic\": 2393\n  },\n  \"net_change\": 50\n}\n```\n\n## Finding\n\nThe displayed reduction50 combines a57 deletion with a7-year change of starting role. Deleting57 from the Fall while retaining rest yields2393, so the2450→2400 relation requires its declared endpoint pairing.\n\n## Reassessment\n\nTest the positive four-node reflection in its actual comparison domain.\n\n## Checks\n\n```json\n{\n  \"paired2450\": true,\n  \"compressed2400\": true,\n  \"controls2393\": true\n}\n```\n\n## Closed utc\n\n2026-09-28T02:06:05.300356+00:00\n\n## Record provenance\n\nExact record hash: `8a43474523aad383d2992ccc8914d6af67746bc2728ff6821508190129210ecd`\n\nSource journal: `Research_Cycles/C0732_C0831/journal.json`", "journalDownload": "/sources/8ea2b882289fbcea5cf11177923617f0c1d1ad7e6eaa3bffb174c6f89699d97d.json", "evidenceLinks": [{"id": "d-9f0e41022cab59a4", "title": "File 53"}]}