Pith Number

pith:AKUS4BPF

pith:2026:AKUS4BPFZWPJMH65K4QOUCZKLE

not attested not anchored not stored refs pending

Depth Registers Unlock W4A4 on SwiGLU: A Reader/Generator Decomposition

Ziyang Liu

Depth registers with a hinge loss control residual reader magnitudes in SwiGLU, unlocking W4A4 quantization performance while leaving the w2 bilinear generator as the dominant error.

arxiv:2604.18128 v2 · 2026-04-20 · cs.CL · cs.AI · cs.LG

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{AKUS4BPFZWPJMH65K4QOUCZKLE}

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

Elementary norm arguments show residual-axis magnitude control bounds readers tightly but leaves w2's bilinear input bounded only by the trivial product of factor bounds; empirically, DR+sink collapses reader kurtosis while leaving generators essentially unchanged, and the reader-rescued W4A4 residue is flat at ~0.28 nats across three matched checkpoints with Delta-remove(w2) dominating.

C2weakest assumption

The partition into residual-axis readers (qkv, w1, w3) and block-internal generators (o_proj, w2) plus the claim that the hinge loss isolates the reader effect without confounding the generator behavior; the paper states its experiments do not isolate the partition from the hinge.

C3one line summary

Depth Registers plus hinge loss cut W4A4-induced perplexity collapse from 1727 to 119 in a 300M SwiGLU model by selectively taming reader-layer activations while leaving bilinear generator tails largely untouched.

Receipt and verification

First computed	2026-05-26T01:03:30.577809Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

02a92e05e5cd9e961fdd5720ea0b2a59282cccade52d3a56e53a9e085b6c02ba

Aliases

arxiv: 2604.18128 · arxiv_version: 2604.18128v2 · doi: 10.48550/arxiv.2604.18128 · pith_short_12: AKUS4BPFZWPJ · pith_short_16: AKUS4BPFZWPJMH65 · pith_short_8: AKUS4BPF

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/AKUS4BPFZWPJMH65K4QOUCZKLE \
  | 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: 02a92e05e5cd9e961fdd5720ea0b2a59282cccade52d3a56e53a9e085b6c02ba

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "4c09c0ad4d68a089a581f23dc3b02438ac5f61780a09847b115bc6d5e4a30ca7",
    "cross_cats_sorted": [
      "cs.AI",
      "cs.LG"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "cs.CL",
    "submitted_at": "2026-04-20T11:47:11Z",
    "title_canon_sha256": "27145865f7d3550908989b73d58c82ada3452e28a4997568cb9fe1166133379c"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.18128",
    "kind": "arxiv",
    "version": 2
  }
}