Pith Number

pith:43SP5VNN

pith:2004:43SP5VNNH4HV35X565UXR7QU7E

not attested not anchored not stored refs pending

Some computations of 1-cohomology groups and construction of non orbit equivalent actions

Sorin Popa

arxiv:math/0407199 v6 · 2004-07-12 · math.OA · math.GR

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{43SP5VNNH4HV35X565UXR7QU7E}

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	2026-07-04T14:38:54.754275Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

e6e4fed5ad3f0f5df6fdf76978fe14f938e73d8c1319a575347ceec260224c8a

Aliases

arxiv: math/0407199 · arxiv_version: math/0407199v6 · doi: 10.48550/arxiv.math/0407199 · pith_short_12: 43SP5VNNH4HV · pith_short_16: 43SP5VNNH4HV35X5 · pith_short_8: 43SP5VNN

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/43SP5VNNH4HV35X565UXR7QU7E \
  | 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: e6e4fed5ad3f0f5df6fdf76978fe14f938e73d8c1319a575347ceec260224c8a

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a229fc6f02039b05d898c9c5e5196a48b46644dedd998f2c52a49f11a158fedf",
    "cross_cats_sorted": [
      "math.GR"
    ],
    "license": "",
    "primary_cat": "math.OA",
    "submitted_at": "2004-07-12T17:51:54Z",
    "title_canon_sha256": "2d76430282538ec8986b70d980f8a60609037ba23e084ec8d3391540e737c76b"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/0407199",
    "kind": "arxiv",
    "version": 6
  }
}