Pith Number

pith:N4KZI6XC

pith:2003:N4KZI6XCEHMPEOPARC7AL3XKFQ

not attested not anchored not stored refs pending

The Hubble Constant from the Gravitational Lens B1608+656

C.D. Fassnacht (UC Davis), G. Surpi (Caltech), L.V.E. Koopmans (Caltech/STScI), R.D. Blandford (Caltech), T. Treu (Caltech)

arxiv:astro-ph/0306216 v2 · 2003-06-11 · 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{N4KZI6XCEHMPEOPARC7AL3XKFQ}

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	2026-07-04T16:37:17.063761Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

6f15947ae221d8f239e088be05eeea2c3ece84172fe9bb9fa1f1a1d3bc627165

Aliases

arxiv: astro-ph/0306216 · arxiv_version: astro-ph/0306216v2 · doi: 10.48550/arxiv.astro-ph/0306216 · pith_short_12: N4KZI6XCEHMP · pith_short_16: N4KZI6XCEHMPEOPA · pith_short_8: N4KZI6XC

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/N4KZI6XCEHMPEOPARC7AL3XKFQ \
  | 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: 6f15947ae221d8f239e088be05eeea2c3ece84172fe9bb9fa1f1a1d3bc627165

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "201248370387193d8a37de26efb6322cdc0cff1bc27ffc8de9d771c412988706",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "astro-ph",
    "submitted_at": "2003-06-11T01:59:39Z",
    "title_canon_sha256": "d9e6cab9f023e386fbbe40ba1d9a5cad76de38d30e0aa45ddfe4af43d9b8e63f"
  },
  "schema_version": "1.0",
  "source": {
    "id": "astro-ph/0306216",
    "kind": "arxiv",
    "version": 2
  }
}