Pith Number

pith:J2XS7DDI

pith:2020:J2XS7DDIQBUWIGQMXP3MPLRPF3

not attested not anchored not stored refs pending

ECH embedding obstructions for rational surfaces

Ben Wormleighton, Julian Chaidez

arxiv:2008.10125 v3 · 2020-08-23 · math.SG · 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{J2XS7DDIQBUWIGQMXP3MPLRPF3}

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	2026-07-05T02:22:05.687004Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

4eaf2f8c688069641a0cbbf6c7ae2f2ed4bc736a41755b0a1d0cf222204c9527

Aliases

arxiv: 2008.10125 · arxiv_version: 2008.10125v3 · doi: 10.48550/arxiv.2008.10125 · pith_short_12: J2XS7DDIQBUW · pith_short_16: J2XS7DDIQBUWIGQM · pith_short_8: J2XS7DDI

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/J2XS7DDIQBUWIGQMXP3MPLRPF3 \
  | 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: 4eaf2f8c688069641a0cbbf6c7ae2f2ed4bc736a41755b0a1d0cf222204c9527

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "393dd84211d257084970a598937c9a29eeef4bfa585c092deefeb922dc6cc1ec",
    "cross_cats_sorted": [
      "math.AG"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.SG",
    "submitted_at": "2020-08-23T22:52:26Z",
    "title_canon_sha256": "b2be816f2bc3cf9833135ffa79234344ae808e24bfc6081f56a2addbc1a3639c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2008.10125",
    "kind": "arxiv",
    "version": 3
  }
}