Pith Number

pith:4PB4Z2M5

pith:2013:4PB4Z2M5Y7G4IFGSB2GAU2NDQA

not attested not anchored not stored refs pending

Quadro-quadric special birational transformations of projective spaces

Alberto Alzati, Jos\'e Carlos Sierra

arxiv:1302.5004 v1 · 2013-02-20 · 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{4PB4Z2M5Y7G4IFGSB2GAU2NDQA}

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	2026-05-18T03:13:35.866414Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e3c3cce99dc7cdc414d20e8c0a69a380249eb46db95188f7d366d3ac768df9fe

Aliases

arxiv: 1302.5004 · arxiv_version: 1302.5004v1 · doi: 10.48550/arxiv.1302.5004 · pith_short_12: 4PB4Z2M5Y7G4 · pith_short_16: 4PB4Z2M5Y7G4IFGS · pith_short_8: 4PB4Z2M5

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/4PB4Z2M5Y7G4IFGSB2GAU2NDQA \
  | 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: e3c3cce99dc7cdc414d20e8c0a69a380249eb46db95188f7d366d3ac768df9fe

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "871fd4b6d96492a488e1af347fee1287decde861b5185f91480625b5951c5bfd",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2013-02-20T15:53:01Z",
    "title_canon_sha256": "6d966a55adcf3277499fbf816227d997c41f229ab1159437be5e42af4da7d7fa"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1302.5004",
    "kind": "arxiv",
    "version": 1
  }
}