Pith Number

pith:VDD2T4CE

pith:2020:VDD2T4CEITR2Y6AMFCKZNDC3VY

not attested not anchored not stored refs pending

On the Ohsawa-Takegoshi extension theorem

Junyan Cao, Mihai Paun

arxiv:2002.04968 v1 · 2020-02-12 · math.CV · math.AG · math.DG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{VDD2T4CEITR2Y6AMFCKZNDC3VY}

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	2026-07-05T00:40:20.185582Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

a8c7a9f04444e3ac780c2895968c5bae118abd01cbc7026a691ea5d0d9521cbe

Aliases

arxiv: 2002.04968 · arxiv_version: 2002.04968v1 · doi: 10.48550/arxiv.2002.04968 · pith_short_12: VDD2T4CEITR2 · pith_short_16: VDD2T4CEITR2Y6AM · pith_short_8: VDD2T4CE

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/VDD2T4CEITR2Y6AMFCKZNDC3VY \
  | 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: a8c7a9f04444e3ac780c2895968c5bae118abd01cbc7026a691ea5d0d9521cbe

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "463808212ee94a847466e807a869ba86ca42f75e4660c1f845add8076c3a5672",
    "cross_cats_sorted": [
      "math.AG",
      "math.DG"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.CV",
    "submitted_at": "2020-02-12T13:26:34Z",
    "title_canon_sha256": "0d1e2d3117e6d746075919a5600e0792820d35a9b7181f1de8895e12c27b0918"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2002.04968",
    "kind": "arxiv",
    "version": 1
  }
}