Pith Number

pith:5SKLNXPG

pith:2012:5SKLNXPGV57BCAPBV4KPXFRBL7

not attested not anchored not stored refs pending

Helmholtz's inverse problem of the discrete calculus of variations

Jacky Cresson, Lo\"ic Bourdin

arxiv:1203.1209 v2 · 2012-03-06 · math.DS

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{5SKLNXPGV57BCAPBV4KPXFRBL7}

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	2026-05-18T01:22:58.182959Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

ec94b6dde6af7e1101e1af14fb96215ff8960692b4fa4427bd917ebdb6727080

Aliases

arxiv: 1203.1209 · arxiv_version: 1203.1209v2 · doi: 10.48550/arxiv.1203.1209 · pith_short_12: 5SKLNXPGV57B · pith_short_16: 5SKLNXPGV57BCAPB · pith_short_8: 5SKLNXPG

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/5SKLNXPGV57BCAPBV4KPXFRBL7 \
  | 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: ec94b6dde6af7e1101e1af14fb96215ff8960692b4fa4427bd917ebdb6727080

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "b8569823b8cb8a9dce10bcca06b4eab3fe924af7b07c4910544c6e96d90bc8ba",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.DS",
    "submitted_at": "2012-03-06T14:32:56Z",
    "title_canon_sha256": "2a987069166fcfcc1f49bd2873dfd2a176cd9e9327ad91a38571221b69575f49"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1203.1209",
    "kind": "arxiv",
    "version": 2
  }
}