Pith Number

pith:HQSHUVM7

pith:2009:HQSHUVM7HXEUSC6EAXTS7Y7KGL

not attested not anchored not stored refs pending

Quantum algorithms know in advance 50% of the solution they will find in the future

Giuseppe Castagnoli

arxiv:0906.1811 v4 · 2009-06-09 · quant-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{HQSHUVM7HXEUSC6EAXTS7Y7KGL}

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	2026-05-18T02:13:21.106852Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

3c247a559f3dc9490bc405e72fe3ea32d8a98c05227ead5b7589f83f2958d6fd

Aliases

arxiv: 0906.1811 · arxiv_version: 0906.1811v4 · doi: 10.48550/arxiv.0906.1811 · pith_short_12: HQSHUVM7HXEU · pith_short_16: HQSHUVM7HXEUSC6E · pith_short_8: HQSHUVM7

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/HQSHUVM7HXEUSC6EAXTS7Y7KGL \
  | 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: 3c247a559f3dc9490bc405e72fe3ea32d8a98c05227ead5b7589f83f2958d6fd

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "da7966c16869e9ec292da16345e8fbfa2547673beb20c2d68a8d5c8dbef07613",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "quant-ph",
    "submitted_at": "2009-06-09T20:00:46Z",
    "title_canon_sha256": "89b769734e05489bdbd1766e971a69ce360229bdd6952dbd558df3a60de76701"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0906.1811",
    "kind": "arxiv",
    "version": 4
  }
}