An ERP digital twin you can walk through
The phrase digital twin usually means a statistical copy of a database you already have: same shapes, same correlations, no real records. This is the other kind. There is no original. The company is generated from accounting rules, and the environment simply lets you read it the way a practitioner reads a real system.
On SAP there is a command field and a registry of display transaction codes, so a purchase order opens with ME23N, an invoice with MIR4, a document with FB03, a vendor's line items with FBL1N and a bank statement with FEBA. Codes that would create or change something resolve to the display screen and say so plainly, because nothing here can be posted. Oracle has no transaction codes, so it navigates by work area and task the way Oracle does, and typing a code says as much. The vocabulary is authentic; the interface is ours.
From a purchase order you can read its release history, follow it to the invoice and the block that held it, then to the payment run, and finally to the bank statement line that cleared the cash, with the reference that ties them. Rows carry a menu for the source document, an evidence pack, an export of exactly what is on screen, and the distinct values of a field in this world.
Seven screens prove the things a sceptic asks about, each stating the layer it tests: every document balances, the trial balance ties to the general ledger journal layer, the per-bank reconciliation proves to the cent, the verified key relationships have zero orphans, the statement tie-out has its artifact, and the reproducibility certificate recomputes every file hash on disk in front of you.
A multi-year world opens one view per fiscal year. An intercompany group opens one view per subsidiary, each on its own platform's screens, plus a consolidation workspace with the elimination schedule and the intercompany registers. Anything you build in the environment can be generated as a full dataset from the same seed, and the package is identical to the world you were just reading.
Read-only, always. Worlds built inside the environment are row-capped so they appear in seconds, while the downloadable packages go far larger. There are no authorisation objects, no security audit log, no table browser and no field-level help, and the Oracle general ledger is not tied to its subledgers. Each of those is stated on the relevant screen rather than left to be discovered.