Pith Number

pith:5UYD6OWD

pith:1998:5UYD6OWD6M5C7CXP7EKQJXERR2

not attested not anchored not stored refs pending

The K-homology class of the Euler characteristic operator is trivial

Jonathan Rosenberg

arxiv:math/9806073 v1 · 1998-06-12 · math.OA · math.DG · math.KT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{5UYD6OWD6M5C7CXP7EKQJXERR2}

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	2026-05-18T04:27:03.890829Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ed303f3ac3f33a2f8aeff91504dc918e9dbfcd62cd6c79d973e2c9176183ce7d

Aliases

arxiv: math/9806073 · arxiv_version: math/9806073v1 · doi: 10.48550/arxiv.math/9806073 · pith_short_12: 5UYD6OWD6M5C · pith_short_16: 5UYD6OWD6M5C7CXP · pith_short_8: 5UYD6OWD

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/5UYD6OWD6M5C7CXP7EKQJXERR2 \
  | 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: ed303f3ac3f33a2f8aeff91504dc918e9dbfcd62cd6c79d973e2c9176183ce7d

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "3fb8af7e761f666b299972c5ce141753d8a013816c39cbd1ad6983e07266b4fd",
    "cross_cats_sorted": [
      "math.DG",
      "math.KT"
    ],
    "license": "",
    "primary_cat": "math.OA",
    "submitted_at": "1998-06-12T19:25:41Z",
    "title_canon_sha256": "a0814de8f33a93ea2cbfb638a27ff5f0876318d98ca86c83f685f5fc02c8b8b6"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/9806073",
    "kind": "arxiv",
    "version": 1
  }
}