Pith Number

pith:F4EB3T2Z

pith:2009:F4EB3T2Z7NXR6WLILD2B5KNQZO

not attested not anchored not stored refs pending

The Johnson homomorphism and its kernel

Andrew Putman

arxiv:0904.0467 v4 · 2009-04-02 · math.GT · 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{F4EB3T2Z7NXR6WLILD2B5KNQZO}

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.

Cited by

1 paper in Pith

Calculating the second rational cohomology group of the Torelli group

Receipt and verification

First computed	2026-07-05T01:08:08.253813Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

2f081dcf59fb6f1f596858f41ea9b0cb81cf6318ef361e8e90124e00d729a2f2

Aliases

arxiv: 0904.0467 · arxiv_version: 0904.0467v4 · doi: 10.48550/arxiv.0904.0467 · pith_short_12: F4EB3T2Z7NXR · pith_short_16: F4EB3T2Z7NXR6WLI · pith_short_8: F4EB3T2Z

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/F4EB3T2Z7NXR6WLILD2B5KNQZO \
  | 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: 2f081dcf59fb6f1f596858f41ea9b0cb81cf6318ef361e8e90124e00d729a2f2

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "042d3f35ad40013fa63f5070cb35d093c8ca37b4ed3f38a50363762208ee12c3",
    "cross_cats_sorted": [
      "math.GR"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GT",
    "submitted_at": "2009-04-02T20:46:06Z",
    "title_canon_sha256": "22fd18d12d7f6faad45fa45da00fb7ee976592210d6587cbef9b557d86936031"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0904.0467",
    "kind": "arxiv",
    "version": 4
  }
}