Pith Number

pith:ORUCDV7X

pith:2012:ORUCDV7XYXT2NR5H4CSKOK3LMB

not attested not anchored not stored refs pending

A spin-foam vertex amplitude with the correct semiclassical limit

Jonathan Engle

arxiv:1201.2187 v2 · 2012-01-10 · gr-qc

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{ORUCDV7XYXT2NR5H4CSKOK3LMB}

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.

Cited by

1 paper in Pith

The problem of time: a path integral view

Receipt and verification

First computed	2026-05-18T01:58:53.063958Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

746821d7f7c5e7a6c7a7e0a4a72b6b605350d9be558bc81774c63bf86a6331eb

Aliases

arxiv: 1201.2187 · arxiv_version: 1201.2187v2 · doi: 10.48550/arxiv.1201.2187 · pith_short_12: ORUCDV7XYXT2 · pith_short_16: ORUCDV7XYXT2NR5H · pith_short_8: ORUCDV7X

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/ORUCDV7XYXT2NR5H4CSKOK3LMB \
  | 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: 746821d7f7c5e7a6c7a7e0a4a72b6b605350d9be558bc81774c63bf86a6331eb

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "602749e26c05b1a001fd5d7159235da946abc02914ed592dde1b400a604ba3fb",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "gr-qc",
    "submitted_at": "2012-01-10T21:19:44Z",
    "title_canon_sha256": "4bb1315b60fc96860ff3da34225510fee2afcb358a7cac9b610848d005784c4c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1201.2187",
    "kind": "arxiv",
    "version": 2
  }
}