Pith Number

pith:I47EHQZC

pith:2011:I47EHQZC4MSBD55RZXENB57F2Z

not attested not anchored not stored refs pending

A surface of general type with p_g=0 and K^2=8 whose universal cover is not the bidisc

Stephen Coughlan

arxiv:1103.4281 v2 · 2011-03-22 · 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{I47EHQZC4MSBD55RZXENB57F2Z}

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	2026-05-18T04:21:52.609623Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

473e43c322e32411f7b1cdc8d0f7e5d668c75c59cb1fa96ac332b50d627b053e

Aliases

arxiv: 1103.4281 · arxiv_version: 1103.4281v2 · doi: 10.48550/arxiv.1103.4281 · pith_short_12: I47EHQZC4MSB · pith_short_16: I47EHQZC4MSBD55R · pith_short_8: I47EHQZC

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/I47EHQZC4MSBD55RZXENB57F2Z \
  | 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: 473e43c322e32411f7b1cdc8d0f7e5d668c75c59cb1fa96ac332b50d627b053e

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "89e2f525768c3dec0564d0e23354905e6a2a81f35e707b8055f6cb3b44ac5964",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2011-03-22T14:56:53Z",
    "title_canon_sha256": "b576ad917de517703284afc7de54625347be620a48e2e86e8ec88ac526152bd5"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1103.4281",
    "kind": "arxiv",
    "version": 2
  }
}