Pith Number

pith:NC7KPJQP

pith:2009:NC7KPJQPXSP3X34UBX5CVV6NA5

not attested not anchored not stored refs pending

Del Pezzo Zoo

Constantin Shramov, Ivan Cheltsov

arxiv:0904.0114 v4 · 2009-04-01 · math.AG · math.DG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{NC7KPJQPXSP3X34UBX5CVV6NA5}

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	2026-05-18T04:05:46.194356Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

68bea7a60fbc9fbbef940dfa2ad7cd0769d254caa825e6a54718a6ade4028cae

Aliases

arxiv: 0904.0114 · arxiv_version: 0904.0114v4 · doi: 10.48550/arxiv.0904.0114 · pith_short_12: NC7KPJQPXSP3 · pith_short_16: NC7KPJQPXSP3X34U · pith_short_8: NC7KPJQP

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/NC7KPJQPXSP3X34UBX5CVV6NA5 \
  | 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: 68bea7a60fbc9fbbef940dfa2ad7cd0769d254caa825e6a54718a6ade4028cae

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "8ba5d2b28f83deab14f353f13dcf5bbc0510037a242ddf494ead1ac04b218883",
    "cross_cats_sorted": [
      "math.DG"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2009-04-01T09:41:01Z",
    "title_canon_sha256": "bb528ab7af12aa21d83db34f9a9182941acf18e650cca9ef2292848a9ac12efc"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0904.0114",
    "kind": "arxiv",
    "version": 4
  }
}