Pith Number

pith:K73MDKVN

pith:2009:K73MDKVNBICKQK4YOWQPFSFX5C

not attested not anchored not stored refs pending

Entropy of the Universe

Marcelo Samuel Berman

arxiv:0904.3135 v1 · 2009-04-20 · physics.gen-ph

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{K73MDKVNBICKQK4YOWQPFSFX5C}

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	2026-05-18T04:33:36.558822Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

57f6c1aaad0a04a82b9875a0f2c8b7e8840b47e1b709d322db50bf35d2967bc3

Aliases

arxiv: 0904.3135 · arxiv_version: 0904.3135v1 · doi: 10.48550/arxiv.0904.3135 · pith_short_12: K73MDKVNBICK · pith_short_16: K73MDKVNBICKQK4Y · pith_short_8: K73MDKVN

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/K73MDKVNBICKQK4YOWQPFSFX5C \
  | 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: 57f6c1aaad0a04a82b9875a0f2c8b7e8840b47e1b709d322db50bf35d2967bc3

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "c856ace4f9256c8ed311426782c0fc61c1481e2e8de8d7ab8a075ce8b1fae768",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "physics.gen-ph",
    "submitted_at": "2009-04-20T23:01:58Z",
    "title_canon_sha256": "a6e6af12e47c46caa13c1e04094c57ca9d163f69bcb63a69159cebf0652b4e1c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0904.3135",
    "kind": "arxiv",
    "version": 1
  }
}