2505.07499
KAM theory at the Quantum resonance
Huanhuan Yuan, Yong Li
incompletemedium confidence
- Category
- Not specified
- Journal tier
- Specialist/Solid
- Processed
- Sep 28, 2025, 12:56 AM
- arXiv Links
- Abstract ↗PDF ↗
Audit review
The paper announces a Gevrey quantum KAM/normal-form result at partial resonances, giving a spectral lattice formula and scarring, but key parts are either misstated or under-specified. Most notably, the “exponentially small in h” remainder is written as O(ε exp(−c h^{1/(α−1)})), which does not decay as h→0 and contradicts the claimed exponential smallness; the natural Gevrey rate is exp(−c h^{−1/(α−1)}). This sign/power issue is repeated in the quantum normal-form section and the main spectral formula (see the abstract and main claims with the O(ε exp(−c h^{1/(α−1)})) term, and the quantum normal-form Proposition with the same rate ). Moreover, the operator is set on L^2(R^l) with translation-invariant principal part H0(hD_x); discrete spectrum and Weyl counting invoked later (on a d-dimensional torus) are not justified without additional compactness or confining assumptions, creating a mismatch of frameworks (R^l vs. T^d) in the scarring section (e.g., the Weyl-law counting and torus microlocalization arguments in Section 6 ). The model solution corrects the exponential rate and outlines a standard Gevrey QBNF/KAM approach with appropriate references, but it also implicitly assumes spectral discreteness/ellipticity or periodic boundary conditions without stating them, and uses projection from quasimodes to true eigenfunctions in a way that fails if the spectrum is continuous. Hence both are incomplete: the paper by incorrect exponent and missing spectral hypotheses; the model by missing global spectral assumptions.
Referee report (LaTeX)
\textbf{Recommendation:} major revisions \textbf{Journal Tier:} specialist/solid \textbf{Justification:} The submission develops a resonant Gevrey KAM reduction and quantum normal form leading to a spectral lattice structure and scarring. However, the stated “exponentially small” Gevrey remainder is written as exp(−c h\^{1/(α−1)}), which does not decay with h→0, contradicting the claim of exponential smallness (this appears repeatedly in the abstract and quantum normal form claims). In addition, the operator is defined on L\^2(R\^ℓ) yet later arguments use Weyl-law counting on a torus and rely on discrete spectrum and spectral projection; compactness/self-adjointness/ellipticity assumptions ensuring discreteness are not stated. These issues should be corrected and hypotheses clarified.