Pith Number

pith:34OKMLS7

pith:2009:34OKMLS7L5N7XB2L3O3EYVJ2NE

not attested not anchored not stored refs pending

The co-Hopfian property of the Johnson kernel and the Torelli group

Yoshikata Kida

arxiv:0911.3923 v6 · 2009-11-20 · math.GR · math.GT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{34OKMLS7L5N7XB2L3O3EYVJ2NE}

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	2026-05-18T03:12:35.480632Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

df1ca62e5f5f5bfb874bdbb64c553a6927f83c3c240263543c93382bb38e1e99

Aliases

arxiv: 0911.3923 · arxiv_version: 0911.3923v6 · doi: 10.48550/arxiv.0911.3923 · pith_short_12: 34OKMLS7L5N7 · pith_short_16: 34OKMLS7L5N7XB2L · pith_short_8: 34OKMLS7

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/34OKMLS7L5N7XB2L3O3EYVJ2NE \
  | 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: df1ca62e5f5f5bfb874bdbb64c553a6927f83c3c240263543c93382bb38e1e99

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a8fc076bd5e2dfba7b11aa3bc60fa66387baf83ff50303d1fadc6978a3a9b18c",
    "cross_cats_sorted": [
      "math.GT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GR",
    "submitted_at": "2009-11-20T13:21:31Z",
    "title_canon_sha256": "fae8ab627185c8aa021a578139cc90b8a6b0e0958e30c29d0100b287cf4707ab"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0911.3923",
    "kind": "arxiv",
    "version": 6
  }
}