Pith Number

pith:IBC4TB2G

pith:2012:IBC4TB2GEPFQAA6PAU6CS7U3RZ

not attested not anchored not stored refs pending

Twistor lines on cubic surfaces

John Armstrong, Massimiliano Povero, Simon Salamon

arxiv:1212.2851 v1 · 2012-12-12 · math.DG · math.AG

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{IBC4TB2GEPFQAA6PAU6CS7U3RZ}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-05-18T01:41:58.333340Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

4045c9874623cb0003cf053c297e9b8e54a7411f6a383ffecbaea9a53dfaadf8

Aliases

arxiv: 1212.2851 · arxiv_version: 1212.2851v1 · doi: 10.48550/arxiv.1212.2851 · pith_short_12: IBC4TB2GEPFQ · pith_short_16: IBC4TB2GEPFQAA6P · pith_short_8: IBC4TB2G

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/IBC4TB2GEPFQAA6PAU6CS7U3RZ \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 4045c9874623cb0003cf053c297e9b8e54a7411f6a383ffecbaea9a53dfaadf8

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6d4c34c9038908176b4fcc04c85ae70439b7bb22b15089f4e34f399e09d97463",
    "cross_cats_sorted": [
      "math.AG"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.DG",
    "submitted_at": "2012-12-12T15:53:40Z",
    "title_canon_sha256": "dff91372b93bbaf4219358abacd32138bceabfd2056c3990445e188a65c77e41"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1212.2851",
    "kind": "arxiv",
    "version": 1
  }
}