Pith Number

pith:QP5HSAXP

pith:2009:QP5HSAXPGUCC7TR5JV5PFJKD2K

not attested not anchored not stored refs pending

Pure states, positive matrix polynomials and sums of hermitian squares

Igor Klep, Markus Schweighofer

arxiv:0907.2260 v3 · 2009-07-13 · math.OA · math.OC

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{QP5HSAXPGUCC7TR5JV5PFJKD2K}

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	2026-05-18T04:24:06.418276Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

83fa7902ef35042fce3d4d7af2a543d2b0bea0fa70e855be5fe9091b71b43a78

Aliases

arxiv: 0907.2260 · arxiv_version: 0907.2260v3 · doi: 10.48550/arxiv.0907.2260 · pith_short_12: QP5HSAXPGUCC · pith_short_16: QP5HSAXPGUCC7TR5 · pith_short_8: QP5HSAXP

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/QP5HSAXPGUCC7TR5JV5PFJKD2K \
  | 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: 83fa7902ef35042fce3d4d7af2a543d2b0bea0fa70e855be5fe9091b71b43a78

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "5120c72cd22cff8a5d2d4fdd010a9ccdd556734e5b1a6e473a6936fef4963ec0",
    "cross_cats_sorted": [
      "math.OC"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.OA",
    "submitted_at": "2009-07-13T22:49:50Z",
    "title_canon_sha256": "fa837d5a92a392a4c06ac1c097a1c374dc1ecd4670de0117edfca5e6052c6e84"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0907.2260",
    "kind": "arxiv",
    "version": 3
  }
}