Pith Number

pith:ZFYY4XZG

pith:2012:ZFYY4XZGKX5KOCM6EEFSBV2E5W

not attested not anchored not stored refs pending

Some Calkin algebras have outer automorphisms

Ernest Schimmerling, Ilijas Farah, Paul McKenney

arxiv:1211.4134 v2 · 2012-11-17 · math.LO · math.OA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{ZFYY4XZGKX5KOCM6EEFSBV2E5W}

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	2026-05-18T03:30:27.719887Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

c9718e5f2655faa7099e210b20d744edb6e96534813adbc7053761758cf25475

Aliases

arxiv: 1211.4134 · arxiv_version: 1211.4134v2 · doi: 10.48550/arxiv.1211.4134 · pith_short_12: ZFYY4XZGKX5K · pith_short_16: ZFYY4XZGKX5KOCM6 · pith_short_8: ZFYY4XZG

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/ZFYY4XZGKX5KOCM6EEFSBV2E5W \
  | 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: c9718e5f2655faa7099e210b20d744edb6e96534813adbc7053761758cf25475

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "bd74bb48f022c965445184321780860a7a4747a20fc6ff11557831e6c5633e4f",
    "cross_cats_sorted": [
      "math.OA"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.LO",
    "submitted_at": "2012-11-17T15:54:23Z",
    "title_canon_sha256": "521d52aaf4623b25c683d5d99e21de07013a1959ae93798ef53988d1e26bf868"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1211.4134",
    "kind": "arxiv",
    "version": 2
  }
}