Pith Number

pith:SFDPJ22P

pith:2009:SFDPJ22PTODOTW2ETKFDSRMPVL

not attested not anchored not stored refs pending

On the dimension of CAT(0) spaces where mapping class groups act

Martin R Bridson

arxiv:0908.0690 v2 · 2009-08-05 · math.GN · math.GR · math.GT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{SFDPJ22PTODOTW2ETKFDSRMPVL}

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	2026-05-18T04:31:50.564508Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

9146f4eb4f9b86e9db449a8a39458faacdbc0788e209c5018a533148f0956785

Aliases

arxiv: 0908.0690 · arxiv_version: 0908.0690v2 · doi: 10.48550/arxiv.0908.0690 · pith_short_12: SFDPJ22PTODO · pith_short_16: SFDPJ22PTODOTW2E · pith_short_8: SFDPJ22P

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/SFDPJ22PTODOTW2ETKFDSRMPVL \
  | 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: 9146f4eb4f9b86e9db449a8a39458faacdbc0788e209c5018a533148f0956785

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "fe555eb968b72315e4c2709ce7c81b1b3bd2a58bc2b52709029c51c13562d44c",
    "cross_cats_sorted": [
      "math.GR",
      "math.GT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.GN",
    "submitted_at": "2009-08-05T15:38:15Z",
    "title_canon_sha256": "34f1b5ba8ccf40147a1484d3e6a8f4e670efb3dacf32003248d661a8f5c1742e"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0908.0690",
    "kind": "arxiv",
    "version": 2
  }
}