Pith Number

pith:Y67PBLHC

pith:2013:Y67PBLHCXGMAR74FHXKWXU2H4C

not attested not anchored not stored refs pending

Birationally rigid Fano threefold hypersurfaces

Ivan Cheltsov, Jihun Park

arxiv:1309.0903 v4 · 2013-09-04 · 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{Y67PBLHCXGMAR74FHXKWXU2H4C}

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	2026-05-18T00:50:58.122195Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

c7bef0ace2b99808ff853dd56bd347e0b2391dd533799597828c0a458e58d1d6

Aliases

arxiv: 1309.0903 · arxiv_version: 1309.0903v4 · doi: 10.48550/arxiv.1309.0903 · pith_short_12: Y67PBLHCXGMA · pith_short_16: Y67PBLHCXGMAR74F · pith_short_8: Y67PBLHC

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/Y67PBLHCXGMAR74FHXKWXU2H4C \
  | 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: c7bef0ace2b99808ff853dd56bd347e0b2391dd533799597828c0a458e58d1d6

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "3c816320c4a06322a08132aa527a240588b5ea925b6899cfde37c38cb7b2e993",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2013-09-04T03:14:23Z",
    "title_canon_sha256": "890d2183677a219d8dba1796532c8616dabf9106887c652d0a8c8682357408b3"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1309.0903",
    "kind": "arxiv",
    "version": 4
  }
}