Pith Number

pith:LLIVNQ74

pith:1997:LLIVNQ74XSDCXTBZCBHW5VQV6I

not attested not anchored not stored refs pending

Observational Evidence Against Birefringence Over Cosmological Distances

J.F.C. Wardle (Brandeis University), M.H. Cohen (Caltech), R.A. Perley (National Radio Astronomy Observatory)

arxiv:astro-ph/9705142 v3 · 1997-05-19 · astro-ph

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{LLIVNQ74XSDCXTBZCBHW5VQV6I}

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	2026-07-04T15:18:05.124557Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

5ad156c3fcbc862bcc39104f6ed615f2357d83f52c758aa0af7b7fda537f32d2

Aliases

arxiv: astro-ph/9705142 · arxiv_version: astro-ph/9705142v3 · doi: 10.48550/arxiv.astro-ph/9705142 · pith_short_12: LLIVNQ74XSDC · pith_short_16: LLIVNQ74XSDCXTBZ · pith_short_8: LLIVNQ74

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/LLIVNQ74XSDCXTBZCBHW5VQV6I \
  | 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: 5ad156c3fcbc862bcc39104f6ed615f2357d83f52c758aa0af7b7fda537f32d2

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "747470ca6a33384d213d4a1cc26bbd666a964697e046f0a7266ff217db1ea53b",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "astro-ph",
    "submitted_at": "1997-05-19T21:06:51Z",
    "title_canon_sha256": "a7a8ed30185530d4191d438bdd196b44f14f0ca3a2c0ab95813a499b0bb6a6fd"
  },
  "schema_version": "1.0",
  "source": {
    "id": "astro-ph/9705142",
    "kind": "arxiv",
    "version": 3
  }
}