Pith Number

pith:GBIK5GBC

pith:2025:GBIK5GBCR66YGFUHLE2CKWAGVV

not attested not anchored not stored refs pending

Obstruction sequences to homotopy equivalences

Coline Emprin

arxiv:2509.17895 v2 · 2025-09-22 · math.AT · math.AG · math.QA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{GBIK5GBCR66YGFUHLE2CKWAGVV}

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	2026-07-29T01:25:29.407648Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

3050ae98228fbd8316875934255806ad68df87766b8080355561170229d9b7ab

Aliases

arxiv: 2509.17895 · arxiv_version: 2509.17895v2 · doi: 10.48550/arxiv.2509.17895 · pith_short_12: GBIK5GBCR66Y · pith_short_16: GBIK5GBCR66YGFUH · pith_short_8: GBIK5GBC

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/GBIK5GBCR66YGFUHLE2CKWAGVV \
  | 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: 3050ae98228fbd8316875934255806ad68df87766b8080355561170229d9b7ab

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6ef2fd387aa56cf61dc2e55daed07f5d1891776f535bd8b10a137a6a14ed6034",
    "cross_cats_sorted": [
      "math.AG",
      "math.QA"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "math.AT",
    "submitted_at": "2025-09-22T15:25:43Z",
    "title_canon_sha256": "11bd7d694e4fde45869f90f97826f50246bf8e5b48c461c3fa6c0c76ba6aaa70"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2509.17895",
    "kind": "arxiv",
    "version": 2
  }
}