Pith Number

pith:QL6WWRCP

pith:2026:QL6WWRCPJ2S5VDHEGSQIJPRGSW

not attested not anchored not stored refs pending

Gauge-independent approach to inflation in quadratic gravity

Adrian Palomares, Jinsu Kim, Ying-li Zhang

The apparent instability of scalar perturbations in quadratic gravity inflation is a gauge artefact rather than a physical issue.

arxiv:2604.22725 v2 · 2026-04-24 · gr-qc · astro-ph.CO · hep-ph · hep-th

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{QL6WWRCPJ2S5VDHEGSQIJPRGSW}

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.

Claims

C1strongest claim

the Newtonian gauge exhibits an apparent instability, characterised by the exponential growth of the metric perturbations. However, this growth is non-generic and gauge-dependent; in the other gauges analysed in this work, the perturbations remain well behaved within the perturbative regime.

C2weakest assumption

Linear perturbation theory remains valid throughout the superhorizon evolution and that the Einstein-frame formulation faithfully captures the physical content without introducing frame-dependent artefacts that affect stability conclusions.

C3one line summary

Apparent instability of metric perturbations in Newtonian gauge for quadratic gravity inflation is a gauge artefact; gauge-invariant variables and other gauges show stable perturbative behaviour.

Receipt and verification

First computed	2026-05-26T02:04:11.293022Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

82fd6b444f4ea5da8ce434a084be2695af838a109724857e4b1300c2b51e9c5b

Aliases

arxiv: 2604.22725 · arxiv_version: 2604.22725v2 · doi: 10.48550/arxiv.2604.22725 · pith_short_12: QL6WWRCPJ2S5 · pith_short_16: QL6WWRCPJ2S5VDHE · pith_short_8: QL6WWRCP

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/QL6WWRCPJ2S5VDHEGSQIJPRGSW \
  | 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: 82fd6b444f4ea5da8ce434a084be2695af838a109724857e4b1300c2b51e9c5b

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "9bc1d7396ef43f8091229e9478a64d61b92fcf1422061d427c9ffc28a06e89bb",
    "cross_cats_sorted": [
      "astro-ph.CO",
      "hep-ph",
      "hep-th"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "gr-qc",
    "submitted_at": "2026-04-24T17:23:52Z",
    "title_canon_sha256": "e26c5145de3c1d9d11b2ffdad46c3895d28b8ad4bcb8b6bc3c6cc86045d7851e"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.22725",
    "kind": "arxiv",
    "version": 2
  }
}