Pith Number

pith:3IHBLPMU

pith:2021:3IHBLPMUUA2JE74KAOAW3T552Q

not attested not anchored not stored refs pending

On the $\sigma_2$-Nirenberg problem on $\mathbb{S}^2$

Han Lu, Siyuan Lu, Yanyan Li

arxiv:2108.02375 v1 · 2021-08-05 · math.AP · math.DG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{3IHBLPMUUA2JE74KAOAW3T552Q}

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	2026-07-05T03:03:32.453373Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

da0e15bd94a034927f8a03816dcfbdd431b88945cae4fdf8bdae36e97591f5e4

Aliases

arxiv: 2108.02375 · arxiv_version: 2108.02375v1 · doi: 10.48550/arxiv.2108.02375 · pith_short_12: 3IHBLPMUUA2J · pith_short_16: 3IHBLPMUUA2JE74K · pith_short_8: 3IHBLPMU

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/3IHBLPMUUA2JE74KAOAW3T552Q \
  | 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: da0e15bd94a034927f8a03816dcfbdd431b88945cae4fdf8bdae36e97591f5e4

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "6ec6de8899f90c0a8f40414b3d79ba5d2c9bb204e1ec53583af71b683722477f",
    "cross_cats_sorted": [
      "math.DG"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.AP",
    "submitted_at": "2021-08-05T05:14:21Z",
    "title_canon_sha256": "3e2b2691d236b01d9462329587cc01b350f2ebc5b8302548add13d1dffb126e1"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2108.02375",
    "kind": "arxiv",
    "version": 1
  }
}