v2 poseidon2b nonlinear-subspace reproduction
Objective
The target is the nonlinear-subspace specialization of ePrint 2026/1792 computed directly from the Poseidon2b parameters and matrices shipped in v2.0.3. The integrated noid_soundness binary reads the production crate; this contract hashes only its complete POSEIDON2B NONLINEAR SUBSPACE REVIEW section, including all four exact Macaulay projections.
Pinned materials
Read contracts/poseidon2b-nonlinear-subspace-reproduction-v2.0.0.md and certificates/README.md. Production and integrated certificate are pinned to 50d6dac5a37b9f1be425b5e6cd823de48f843b50 in https://git.parano1d.org/ignotusnemo/parano1d. Obtain the complete production checkout and inspect the relevant code before executing the protected reproduction. This research workspace supplies the frozen contract, verified input files and passive verifier.
Required result
The protected runner executes the current production noid_soundness binary with --exact, extracts exactly one complete nonlinear-subspace section and checks its SHA-256, rank core, trail lengths and lowest projected attack cost. Other sections of that binary retain a historical aggregate profile and are excluded from this component contract. The joint-bank v2 result is checked by the separate current certificate reproduction task.
Commands and output
Set PARANO1D_PRODUCTION_DIR as documented in certificates/README.md. From the research directory, run npm ci, create a workspace with npm run challenge -- setup --track poseidon2b-nonlinear-subspace-reproduction --id <your-result> <your attribution options>, then run npm run challenge -- verify --submission <directory>. Return the generated passive submission.json only after the local verifier returns accepted.
Do not modify calculator sources, expected values, input files, contracts or verifier code. An altered field, source pin or input digest must fail. The nonzero core is 0000000000000000000000000000be32, trail lengths are two and four, and the lowest semi-regular projection is 1022.830074998558 bits. This is a scoped component calculation, not a 1022-bit security claim, a universal lower bound or a production reachability witness.