Pith Number

pith:QPJJG7YB

pith:2009:QPJJG7YBSXQDJMY2BFQX5UIBUE

not attested not anchored not stored refs pending

Groups acting freely on $\Lambda$-trees

A. Myasnikov, D. Serbin, O. Kharlampovich

arxiv:0911.0209 v4 · 2009-11-01 · 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{QPJJG7YBSXQDJMY2BFQX5UIBUE}

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	2026-05-18T02:24:46.488863Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

83d2937f0195e034b31a09617ed101a132c96de7dc95428411824d53a3335e91

Aliases

arxiv: 0911.0209 · arxiv_version: 0911.0209v4 · doi: 10.48550/arxiv.0911.0209 · pith_short_12: QPJJG7YBSXQD · pith_short_16: QPJJG7YBSXQDJMY2 · pith_short_8: QPJJG7YB

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/QPJJG7YBSXQDJMY2BFQX5UIBUE \
  | 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: 83d2937f0195e034b31a09617ed101a132c96de7dc95428411824d53a3335e91

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "1b5ef7c4c54d8575bc478c069fbc7041a5fd6870f97a26a57f783d1e80bdb41f",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GR",
    "submitted_at": "2009-11-01T21:34:22Z",
    "title_canon_sha256": "715d154ba66fde3f45f27194e0737e4adb2ac297e2fcd508ed204141e55109ed"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0911.0209",
    "kind": "arxiv",
    "version": 4
  }
}