Pith Number

pith:XSNNYXA2

pith:2026:XSNNYXA2LOTWSQV63OAMK55YGB

not attested not anchored not stored refs pending

Beyond Invariant Dictionary: Data-Driven Koopman Spectral Recovery with Filtered Extended Dynamic Mode Decomposition

Igor Mezi\'c, Siji Chen, Sui Tang

arxiv:2608.02661 v1 · 2026-08-01 · math.NA · cs.IT · cs.NA · math.DS · math.IT

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{XSNNYXA2LOTWSQV63OAMK55YGB}

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	2026-08-05T00:38:18.196957Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

bc9adc5c1a5ba76942bedb80c577b83061d73cc809158dbfae79f2b64ed36e1b

Aliases

arxiv: 2608.02661 · arxiv_version: 2608.02661v1 · doi: 10.48550/arxiv.2608.02661 · pith_short_12: XSNNYXA2LOTW · pith_short_16: XSNNYXA2LOTWSQV6 · pith_short_8: XSNNYXA2

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/XSNNYXA2LOTWSQV63OAMK55YGB \
  | 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: bc9adc5c1a5ba76942bedb80c577b83061d73cc809158dbfae79f2b64ed36e1b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "1a7fd0f5b8e1ff1b7effa13acfe75e0b52f14af31c8c3781ec19be11a19e0ff6",
    "cross_cats_sorted": [
      "cs.IT",
      "cs.NA",
      "math.DS",
      "math.IT"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "math.NA",
    "submitted_at": "2026-08-01T18:47:19Z",
    "title_canon_sha256": "4ba8fa8826811571469b8e2de04b7ba8f053f60590421445f7f5a182d79e68f3"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2608.02661",
    "kind": "arxiv",
    "version": 1
  }
}