Pith Number

pith:IVEMD2RM

pith:2025:IVEMD2RMDPFM7CZY6Z2MNVVYDL

not attested not anchored not stored refs pending

GRPO is Secretly a Process Reward Model

Alexander Koller, Michael Sullivan

arxiv:2509.21154 v4 · 2025-09-25 · cs.LG · cs.AI

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{IVEMD2RMDPFM7CZY6Z2MNVVYDL}

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	2026-05-29T02:05:36.365588Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

4548c1ea2c1bcacf8b38f674c6d6b81ae7c1f5c95de198135a1baf56c09bf5a9

Aliases

arxiv: 2509.21154 · arxiv_version: 2509.21154v4 · doi: 10.48550/arxiv.2509.21154 · pith_short_12: IVEMD2RMDPFM · pith_short_16: IVEMD2RMDPFM7CZY · pith_short_8: IVEMD2RM

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/IVEMD2RMDPFM7CZY6Z2MNVVYDL \
  | 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: 4548c1ea2c1bcacf8b38f674c6d6b81ae7c1f5c95de198135a1baf56c09bf5a9

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "568cb2708829e3bd83c602f2ca9d8ffb72a97e94dbe41b88593c72e057b730cb",
    "cross_cats_sorted": [
      "cs.AI"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "cs.LG",
    "submitted_at": "2025-09-25T13:40:36Z",
    "title_canon_sha256": "8ccdd1feaf668166a1a097e72641217affdce7de6a4405524820638bb5abce00"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2509.21154",
    "kind": "arxiv",
    "version": 4
  }
}