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Pith Number

pith:N4BCK4MV

pith:1993:N4BCK4MVZUFHPTWLB5SJBCBPTA
not attested not anchored not stored refs pending

van Vleck determinants: geodesic focussing and defocussing in Lorentzian spacetimes

Matt Visser

arxiv:hep-th/9303020 v1 · 1993-03-03 · hep-th · gr-qc

Add to your LaTeX paper
\usepackage{pith}
\pithnumber{N4BCK4MVZUFHPTWLB5SJBCBPTA}

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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

3 papers in Pith

Receipt and verification
First computed 2026-07-04T15:55:56.479204Z
Builder pith-number-builder-2026-05-17-v1
Signature Pith Ed25519 (pith-v1-2026-05) · public key
Schema pith-number/v1.0

Canonical hash

6f02257195cd0a77cecb0f6490882f981bd72ac57f55cee1251734834d7d046d

Aliases

arxiv: hep-th/9303020 · arxiv_version: hep-th/9303020v1 · doi: 10.48550/arxiv.hep-th/9303020 · pith_short_12: N4BCK4MVZUFH · pith_short_16: N4BCK4MVZUFHPTWL · pith_short_8: N4BCK4MV
Agent API
Verify this Pith Number yourself
curl -sH 'Accept: application/ld+json' https://pith.science/pith/N4BCK4MVZUFHPTWLB5SJBCBPTA \
  | 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: 6f02257195cd0a77cecb0f6490882f981bd72ac57f55cee1251734834d7d046d
Canonical record JSON
{
  "metadata": {
    "abstract_canon_sha256": "5cb17d34ce48e4fa1ed5403b4825703a73917ab79d5d0dfed265f5e153e81224",
    "cross_cats_sorted": [
      "gr-qc"
    ],
    "license": "",
    "primary_cat": "hep-th",
    "submitted_at": "1993-03-03T17:57:10Z",
    "title_canon_sha256": "5d32cd534781f07c57f53cbad7cfdcdc3e5f252f4fceed27f70084d1a0a64419"
  },
  "schema_version": "1.0",
  "source": {
    "id": "hep-th/9303020",
    "kind": "arxiv",
    "version": 1
  }
}