Pith Number

pith:U4UEXP6K

pith:2004:U4UEXP6KNQKWRBY6FDYKKROGBL

not attested not anchored not stored refs pending

Space-to-ground quantum-communication using an optical ground station: a feasibility study

A. Zeilinger, C. Barbieri, C. Pernechele, F. Tamburini, G. Bianco, M. Aspelmeyer, P. Villoresi, R. Ursin, T. Jennewein

arxiv:quant-ph/0408067 v1 · 2004-08-10 · 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{U4UEXP6KNQKWRBY6FDYKKROGBL}

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	2026-05-18T01:37:58.437096Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

a7284bbfca6c1568871e28f0a545c60aed1cc99134efe660c98474ec61d6b1c5

Aliases

arxiv: quant-ph/0408067 · arxiv_version: quant-ph/0408067v1 · doi: 10.48550/arxiv.quant-ph/0408067 · pith_short_12: U4UEXP6KNQKW · pith_short_16: U4UEXP6KNQKWRBY6 · pith_short_8: U4UEXP6K

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/U4UEXP6KNQKWRBY6FDYKKROGBL \
  | 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: a7284bbfca6c1568871e28f0a545c60aed1cc99134efe660c98474ec61d6b1c5

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "641af84a3f1d5efed1359efa913f55c5da7354c7fec97d151942310aebcd6909",
    "cross_cats_sorted": [],
    "license": "",
    "primary_cat": "quant-ph",
    "submitted_at": "2004-08-10T20:00:57Z",
    "title_canon_sha256": "e0c3b46f9176757eec8e81385540091ce9228b1dca09999f5990ef1307cd54b6"
  },
  "schema_version": "1.0",
  "source": {
    "id": "quant-ph/0408067",
    "kind": "arxiv",
    "version": 1
  }
}