Pith Number

pith:6NHZYCBP

pith:2000:6NHZYCBPB7YA2MXWSJ262YAWFJ

not attested not anchored not stored refs pending

Obstructions to nonnegative curvature and rational homotopy theory

Igor Belegradek, Vitali Kapovitch

arxiv:math/0007007 v4 · 2000-07-01 · math.DG · math.AT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{6NHZYCBPB7YA2MXWSJ262YAWFJ}

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	2026-05-18T00:35:44.632701Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

f34f9c082f0ff00d32f69275ed60162a4503bbc546b97adb342c17c6e548b0ff

Aliases

arxiv: math/0007007 · arxiv_version: math/0007007v4 · doi: 10.48550/arxiv.math/0007007 · pith_short_12: 6NHZYCBPB7YA · pith_short_16: 6NHZYCBPB7YA2MXW · pith_short_8: 6NHZYCBP

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/6NHZYCBPB7YA2MXWSJ262YAWFJ \
  | 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: f34f9c082f0ff00d32f69275ed60162a4503bbc546b97adb342c17c6e548b0ff

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "7d30147e77af72cfcfa69c89d12f54d7482aeac193d439182f91783acc23601c",
    "cross_cats_sorted": [
      "math.AT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.DG",
    "submitted_at": "2000-07-01T17:18:39Z",
    "title_canon_sha256": "e5401bb62edbdb000117bc1a7fda964c6e4ae8f736f6af5ff444f9accc1f5a70"
  },
  "schema_version": "1.0",
  "source": {
    "id": "math/0007007",
    "kind": "arxiv",
    "version": 4
  }
}