Pith Number

pith:BQQ2YNHG

pith:2011:BQQ2YNHGD5XY3N2KKI2KP2RSY5

not attested not anchored not stored refs pending

HI signatures of galaxy evolution

J.M. van der Hulst

arxiv:1103.1420 v1 · 2011-03-08 · astro-ph.CO · astro-ph.GA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{BQQ2YNHGD5XY3N2KKI2KP2RSY5}

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

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	2026-05-18T04:27:15.874089Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

0c21ac34e61f6f8db74a5234a7ea32c7555bde9e011efe988034bcd7a742ef58

Aliases

arxiv: 1103.1420 · arxiv_version: 1103.1420v1 · doi: 10.48550/arxiv.1103.1420 · pith_short_12: BQQ2YNHGD5XY · pith_short_16: BQQ2YNHGD5XY3N2K · pith_short_8: BQQ2YNHG

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/BQQ2YNHGD5XY3N2KKI2KP2RSY5 \
  | 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: 0c21ac34e61f6f8db74a5234a7ea32c7555bde9e011efe988034bcd7a742ef58

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "f95d324575f5014d4f71e622e8e00cbed42f1dba094c0e88166a0a038844712f",
    "cross_cats_sorted": [
      "astro-ph.GA"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "astro-ph.CO",
    "submitted_at": "2011-03-08T02:50:30Z",
    "title_canon_sha256": "9367999136b29fee829bfef2f64f2a8e5a7b427ee0a7a48aa52cd0bab4742b7f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1103.1420",
    "kind": "arxiv",
    "version": 1
  }
}