Pith Number

pith:BU5YIS4P

pith:1989:BU5YIS4PK6J2YHIPTVPNN353OC

not attested not anchored not stored refs pending

Shadows of convex bodies

Keith Ball

arxiv:math/9201204 v1 · 1989-10-26 · math.MG · math.FA

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{BU5YIS4PK6J2YHIPTVPNN353OC}

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	2026-05-18T01:05:54.693120Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

0d3b844b8f5793ac1d0f9d5ed6efbb70a2964634a81ee7028ac1d6ea0ab8949b

Aliases

arxiv: math/9201204 · arxiv_version: math/9201204v1 · doi: 10.48550/arxiv.math/9201204 · pith_short_12: BU5YIS4PK6J2 · pith_short_16: BU5YIS4PK6J2YHIP · pith_short_8: BU5YIS4P

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/BU5YIS4PK6J2YHIPTVPNN353OC \
  | 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: 0d3b844b8f5793ac1d0f9d5ed6efbb70a2964634a81ee7028ac1d6ea0ab8949b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a8d8074242d56d1aff060e70f4414b7c7c323796853da76945c5498afc239c2a",
    "cross_cats_sorted": [
      "math.FA"
    ],
    "license": "",
    "primary_cat": "math.MG",
    "submitted_at": "1989-10-26T14:59:00Z",
    "title_canon_sha256": "75094d267fdf41a69dd371de4308dd105fd0bdb0880a81e43f1a8c322065a11d"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/9201204",
    "kind": "arxiv",
    "version": 1
  }
}