Pith Number

pith:B4HZF4QA

pith:2017:B4HZF4QAMY73VWWV5R6DGNGJ2P

not attested not anchored not stored refs pending

On the motivic class of the classifying stack of $G_2$ and the spin groups

Mattia Talpo, Roberto Pirisi

arxiv:1702.02649 v2 · 2017-02-08 · math.AG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{B4HZF4QAMY73VWWV5R6DGNGJ2P}

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	2026-05-18T00:37:54.608777Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

0f0f92f200663fbadad5ec7c3334c9d3fc3c9d085fa0e7c0b8403637563aa85f

Aliases

arxiv: 1702.02649 · arxiv_version: 1702.02649v2 · doi: 10.48550/arxiv.1702.02649 · pith_short_12: B4HZF4QAMY73 · pith_short_16: B4HZF4QAMY73VWWV · pith_short_8: B4HZF4QA

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/B4HZF4QAMY73VWWV5R6DGNGJ2P \
  | 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: 0f0f92f200663fbadad5ec7c3334c9d3fc3c9d085fa0e7c0b8403637563aa85f

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "1e132a1847dfab0c632f737dd02f2588b22959d57ba693bd53838068c59d5d6c",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AG",
    "submitted_at": "2017-02-08T23:05:49Z",
    "title_canon_sha256": "6d20576e10a521a81f87c3df2a55156ac14d3acd2da1bbed7e1b04c087cc2f80"
  },
  "schema_version": "1.0",
  "source": {
    "id": "1702.02649",
    "kind": "arxiv",
    "version": 2
  }
}