Pith Number

pith:SE4UHC4K

pith:2009:SE4UHC4KBINGFDDJ63DGTK6YP5

not attested not anchored not stored refs pending

Universal covering spaces and fundamental groups in algebraic geometry as schemes

Kirsten Wickelgren, Ravi Vakil

arxiv:0902.3464 v4 · 2009-02-19 · math.AG · math.AT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{SE4UHC4KBINGFDDJ63DGTK6YP5}

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	2026-05-18T04:30:02.996527Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

9139438b8a0a1a628c69f6c669abd87f5da89811b64d262cface48203231e1a8

Aliases

arxiv: 0902.3464 · arxiv_version: 0902.3464v4 · doi: 10.48550/arxiv.0902.3464 · pith_short_12: SE4UHC4KBING · pith_short_16: SE4UHC4KBINGFDDJ · pith_short_8: SE4UHC4K

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/SE4UHC4KBINGFDDJ63DGTK6YP5 \
  | 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: 9139438b8a0a1a628c69f6c669abd87f5da89811b64d262cface48203231e1a8

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6d1e6f96a4e784df0452522b7487e1a5e2121031a45cd02f28b1665aa3d2b800",
    "cross_cats_sorted": [
      "math.AT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2009-02-19T21:15:08Z",
    "title_canon_sha256": "3ec133ca4347074e15b95c62065579165e3da0fa65706e151ad16bb6137e6bff"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0902.3464",
    "kind": "arxiv",
    "version": 4
  }
}