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pith:BHIDWZHM

pith:2026:BHIDWZHMCCWWEZOGXS6YFL42XD
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Singular Asymptotics of SPADE in Quantum Source Discrimination

Natsuki Kariya

SPADE and direct imaging share the same leading log canonical threshold but differ in multiplicity for aligned sources, while misalignment shifts their discrimination scales and creates an exact blind separation for binary-SPADE.

arxiv:2605.14432 v1 · 2026-05-14 · quant-ph · math.ST · stat.ME · stat.TH

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Record completeness

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2 Internet Archive
3 Author claim open · sign in to claim
4 Citations open
5 Replications open
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Claims

C1strongest claim

In the aligned Gaussian case, direct imaging and SPADE share the same real log canonical threshold λ=1/2 but differ in multiplicity, yielding a universal subleading advantage of aligned SPADE in the local prior-weighted regime. In the misaligned setting, misaligned binary-SPADE and direct imaging acquire nontrivial local power on different intrinsic scales s=O(n^{-1/4}) and s=O(n^{-1/2}), respectively, with binary-SPADE exhibiting an exact blind separation s*=2θ.

C2weakest assumption

The analysis assumes a Gaussian point-spread function and that a binary-SPADE reduction retains the full leading O(s^2) leakage contrast near alignment, with higher-mode corrections entering only at O(s^4); if the actual optical response deviates from this model, the claimed scaling and blind-spot results may not apply.

C3one line summary

Aligned SPADE shares the log canonical threshold λ=1/2 with direct imaging but gains a subleading advantage, while misaligned binary-SPADE shows different power scaling and an exact blind spot at s*=2θ.

References

15 extracted · 15 resolved · 0 Pith anchors

[1] M. Tsang, R. Nair, and X.-M. Lu, Phys. Rev. X6, 031033 (2016) 2016
[2] R. Nair and M. Tsang, Phys. Rev. Lett.117, 190801 (2016) 2016
[3] X.-M. Lu, H. Krovi, R. Nair, S. Guha, and J. H. Shapiro, npj Quantum Inf.4, 64 (2018) 2018
[4] M. Pa´ ur, B. Stoklasa, Z. Hradil, L. L. S´ anchez-Soto, and J. ˇReh´ aˇ cek, Optica3, 1144–1147 (2016) 2016
[5] Z. Huang and C. Lupo, Phys. Rev. Lett.127, 130502 (2021) 2021
Receipt and verification
First computed 2026-05-17T23:39:07.118967Z
Builder pith-number-builder-2026-05-17-v1
Signature Pith Ed25519 (pith-v1-2026-05) · public key
Schema pith-number/v1.0

Canonical hash

09d03b64ec10ad6265c6bcbd82af9ab8ebea5143e522e11274db5561ddc80620

Aliases

arxiv: 2605.14432 · arxiv_version: 2605.14432v1 · doi: 10.48550/arxiv.2605.14432 · pith_short_12: BHIDWZHMCCWW · pith_short_16: BHIDWZHMCCWWEZOG · pith_short_8: BHIDWZHM
Agent API
Verify this Pith Number yourself
curl -sH 'Accept: application/ld+json' https://pith.science/pith/BHIDWZHMCCWWEZOGXS6YFL42XD \
  | 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: 09d03b64ec10ad6265c6bcbd82af9ab8ebea5143e522e11274db5561ddc80620
Canonical record JSON
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    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "quant-ph",
    "submitted_at": "2026-05-14T06:26:41Z",
    "title_canon_sha256": "81910edc13e39faa1b1a2ba7ff5c5437f9adf0c4b1afd0260904b4b4b0bea922"
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