Pith Number

pith:N3NIPBR4

pith:2008:N3NIPBR442QB4DFHVVPWD4D6PZ

not attested not anchored not stored refs pending

On time reversal mirrors

Albert C. Fannjiang

arxiv:0811.0132 v2 · 2008-11-02 · physics.optics · physics.gen-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{N3NIPBR442QB4DFHVVPWD4D6PZ}

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	2026-05-18T02:15:22.497935Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

6eda87863ce6a01e0ca7ad5f61f07e7e7bdee7c7893d7358d53fbe5e8014d4d7

Aliases

arxiv: 0811.0132 · arxiv_version: 0811.0132v2 · doi: 10.48550/arxiv.0811.0132 · pith_short_12: N3NIPBR442QB · pith_short_16: N3NIPBR442QB4DFH · pith_short_8: N3NIPBR4

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/N3NIPBR442QB4DFHVVPWD4D6PZ \
  | 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: 6eda87863ce6a01e0ca7ad5f61f07e7e7bdee7c7893d7358d53fbe5e8014d4d7

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6b4735db9816bfb83002eb1ce4dc883a3989c6767e304ef719916ed9dda465c6",
    "cross_cats_sorted": [
      "physics.gen-ph"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "physics.optics",
    "submitted_at": "2008-11-02T06:11:36Z",
    "title_canon_sha256": "992a96d11ea237d673868cf04f777fa929c7e8857e85a571ad5ee9fa160849c2"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0811.0132",
    "kind": "arxiv",
    "version": 2
  }
}