Pith Number

pith:FIGGGCWU

pith:2026:FIGGGCWUIVGB7OUJRLZOH3BQKE

not attested not anchored not stored refs pending

The unreasonable effectiveness of the cathetus rule in ancient and modern optics

Gavin R. Putland

arxiv:2606.28851 v1 · 2026-06-27 · physics.hist-ph · physics.optics

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{FIGGGCWUIVGB7OUJRLZOH3BQKE}

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	2026-06-30T01:16:54.485780Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

2a0c630ad4454c1fba898af2e3ec30512641610bc457588f7b1b2a6353d226c8

Aliases

arxiv: 2606.28851 · arxiv_version: 2606.28851v1 · doi: 10.48550/arxiv.2606.28851 · pith_short_12: FIGGGCWUIVGB · pith_short_16: FIGGGCWUIVGB7OUJ · pith_short_8: FIGGGCWU

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/FIGGGCWUIVGB7OUJRLZOH3BQKE \
  | 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: 2a0c630ad4454c1fba898af2e3ec30512641610bc457588f7b1b2a6353d226c8

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "5daa3abcbc1ba8dc6d8dfe30471900fd2411e9322fbf413dd2d093e4f8d7e3fd",
    "cross_cats_sorted": [
      "physics.optics"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "physics.hist-ph",
    "submitted_at": "2026-06-27T10:25:21Z",
    "title_canon_sha256": "71f9d291e00c2439976c0b8e39e3613ccf627663d6d0f99a7519508481b9038a"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2606.28851",
    "kind": "arxiv",
    "version": 1
  }
}