Pith. sign in

REVIEW 3 major objections 5 minor 56 references

Decay estimates for discrete bi-Laplace operators with potentials on the lattice $\mathbb{Z}$

T0 review · 3 major / 5 minor · reviewed 2026-08-06 · deepseek-v4-flash

Pith's one-line read Lattice fourth-order Schrödinger dynamics disperse at the continuous rate $|t|^{-1/4}$, with a complete resonance classification, after excluding positive eigenvalues.

desk verdict Genuinely new decay estimates for discrete bi-Laplace operators, but the headline perturbed result is conditional on an unproved no-eigenvalue assumption that the abstract omits. read the letter →

arxiv 2506.23119 v1 pith:4LGZRHIE submitted 2025-06-29 math.AP

classification math.AP MSC 35Q4147B3981Q10
keywords discretebi-Laplaceoperatordecayestimatesresonanceclassificationlimitingabsorptionprincipleell-1toell-infinitybeamequationthresholdexpansions
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper establishes that on the lattice $\mathbb{Z}$ the fourth-order Schrödinger flow generated by the discrete bi-Laplacian $\Delta^2$ decays like $|t|^{-1/4}$ from $\ell^1$ to $\ell^\infty$, the same rate as for the continuous fourth-order operator on $\mathbb{R}$, and that this rate is sharp for $V=0$. For perturbed operators $H=\Delta^2+V$ with real decaying potentials, it proves the same $|t|^{-1/4}$ decay for the absolutely continuous part $e^{-itH}P_{ac}(H)$, and $|t|^{-1/3}$ decay for the associated discrete beam evolution, provided $H$ has no positive eigenvalues in $(0,16)$ and the potential decays fast enough depending on the resonance type at $0$. The proof works by proving a limiting absorption principle for $H$, expanding the boundary resolvent near the two thresholds $0$ and $16$, and classifying all resonance types there; this is the first analysis of its kind for a higher-order discrete Schrödinger operator. A sympathetic reader would care because one basic expectation of lattice dispersion—that discreteness slows decay down—is shown to fail for fourth-order operators, and the result supplies the full resonance-typed picture needed for scattering and nonlinear applications.

What carries the argument

The engine of the proof is Stone's formula written in the spectral variable $\mu$ with $\lambda=\mu^4$, so that the decay problem becomes a family of oscillatory integrals in $\mu$ over $(0,2)$. The free resolvent boundary values $R^\pm_0(\mu^4)$ have the explicit kernel $\frac1{4\mu^3}(\pm i a_1(\mu)e^{\mp i\theta_+|n-m|}+a_2(\mu)e^{b(\mu)|n-m|})$, whose singularities near $\mu=0$ and $\mu=2$ are expanded by powers of $\mu$ and $(2-\mu)^{1/2}$; perturbation is organized through the effective operator $M^\pm(\mu)=U+vR^\pm_0(\mu^4)v$, whose invertibility (guaranteed by the no-positive-eigenvalue assumption) converts $R^\pm_V(\mu^4)$ into $R^\pm_0(\mu^4)-R^\pm_0(\mu^4)v(M^\pm(\mu))^{-1}vR^\pm_0(\mu^4)$. The resonance classification is encoded in finite-codimensional projections $S_j$ and $\widetilde S_j$ built from the moments of $v$, which decide how many powers of $\mu$ are lost in the Neumann expansion. A standard oscillatory-integral estimate with phases $(2-2\cos\theta)^2$ having a fourth-order critical point at $\theta=0$ converts each expansion into the $|t|^{-1/4}$ bound, while the same phase at $\mu=2$ after conjugation by $J\phi(n)=(-1)^n\phi(n)$ produces half-integer powers and the beam-flow estimates.

What would settle it

Find a potential $V$ with $|V(n)|\lesssim\langle n\rangle^{-\beta}$ (for example compactly supported) for which the difference equation $(\Delta^2+V)\phi=\lambda\phi$ has a nonzero $\ell^2(\mathbb{Z})$ solution for some $\lambda\in(0,16)$; such a discovery would make the hypothesis of Theorem 1.2 false for that potential and would break the invertibility of $M^\pm(\mu)$ on which the resolvent expansion and decay proof depend.

Watch

Extended reading notes

Core claim

On the paper's own terms, the central claim is that $H=\Delta^2+V$ on $\ell^2(\mathbb{Z})$, with real $V$ obeying $|V(n)|\lesssim\langle n\rangle^{-\beta}$ and with no positive eigenvalues in $I=(0,16)$, satisfies $$\|$e^{{-itH}}$P_{ac}(H)\|_{\$ell^{1}$\to\ell^\infty}\lesssim|t|^{-1/4}$$ and $$\|\cos(t\sqrt H)P_{ac}(H)\|_{\$ell^{1}$\to\ell^\infty}+\left\|\frac{\sin(t\sqrt H)}{t\sqrt H}P_{ac}(H)\right\|_{\$ell^{1}$\to\ell^\infty}\lesssim|t|^{-1/3},$$ and that for $V=0$ the $|t|^{-1/4}$ exponent is optimal. The required decay of $V$ is $\beta>15$, $19$, or $27$ according as $0$ is regular, a first-kind resonance, or a second-kind resonance; near $16$, the requirements are $\beta>7$, $11$, or $15$ in the regular, resonance, and eigenvalue cases. These estimates cover all resonance types at both thresholds, with a complete characterization of the resonance spaces in weighted $\ell^2$ spaces.

Load-bearing premise

The load-bearing premise is that $H=\Delta^2+V$ has no positive eigenvalues in the continuous-spectrum interval $(0,16)$; the paper does not prove this for the general decaying potentials it allows, citing only the $\delta$-potential case and calling for further study.

Editorial extensions

If this is right

  • For $V=0$ the $\ell^1\to\ell^\infty$ rate $|t|^{-1/4}$ is sharp, and it yields Strichartz estimates in the admissible range $1/q+1/(4r)\le 1/8$, with a counterexample built from narrowly localized data excluding any faster rate.
  • For $H=\Delta^2+V$, the absolutely continuous part of the fourth-order Schrödinger flow decays at the same $|t|^{-1/4}$ rate even when $0$ is a first- or second-kind resonance or $16$ is a resonance or eigenvalue; only the required decay of $V$ changes.
  • The beam-flow combination $\cos(t\sqrt H)P_{ac}(H)+(\sin(t\sqrt H)/(t\sqrt H))P_{ac}(H)$ has decay $|t|^{-1/3}$, matching the second-order discrete wave and beam decay.
  • The threshold classification is complete in the sense that $S_3\ell^2=\{0\}=\widetilde S_2\ell^2$ for $\beta>9$, so the zero-energy eigenvalue case is excluded and all remaining zero and sixteen resonant types are captured by the projections listed in Theorem 1.7.
  • The discrete Schrödinger and beam equations therefore have solutions whose continuous spectral parts disperse exactly as their continuous counterparts, with discrete eigenvalue parts contributing no decay or exponential growth.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Editorial inference: the same machinery should transfer to other higher-order difference operators whose symbol has a degenerate critical point, with the decay exponent presumably set by the order of the first nonvanishing derivative of the symbol.
  • Editorial inference: because the no-positive-eigenvalue hypothesis is only verified in the paper for a $\delta$-potential, a natural next step is to prove absence of embedded positive eigenvalues for compactly supported or short-range potentials, or to find a counterexample; the theorem's range of validity expands or contracts accordingly.
  • Editorial inference: the half-integer power expansions at $\mu=2$ suggest that the threshold $16$ behaves like a nondegenerate edge for the conjugated operator $JHJ$, which may make endpoint or weighted estimates at the top of the spectrum behave differently from the bottom threshold.
  • Editorial inference: the Strichartz sharpness from localized data suggests the discrete bi-Schrödinger equation lies in the same admissible family as the continuous fourth-order equation, so nonlinear well-posedness theory on $\mathbb{Z}$ could be developed along the same admissibility range.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. This paper studies time-decay estimates for the fourth-order discrete Schrödinger operator H = Δ² + V on ℓ²(Z) and for the associated beam evolution. For V ≡ 0, it proves the sharp bound ∥e^{-itΔ²}∥_{ℓ¹→ℓ^∞} ≲ |t|^{-1/4}, matching the continuous one-dimensional bi-Schrödinger rate and contrasting with the slower |t|^{-1/3} rate of e^{itΔ} (Theorems 3.1 and 3.5, with a Knapp-type Strichartz sharpness argument). For nonzero potentials with |V(n)| ≲ ⟨n⟩^{-β}, the main theorem (Theorem 1.2) asserts that if H has no positive eigenvalues in I=(0,16), then for β>15 (0 regular), β>19 (first-kind resonance at 0), or β>27 (second-kind resonance at 0), one has ∥e^{-itH}P_ac(H)∥_{ℓ¹→ℓ^∞} ≲ |t|^{-1/4}, together with the beam estimate ∥cos(t√H)P_ac(H)∥ + ∥sin(t√H)/(t√H)P_ac(H)∥ ≲ |t|^{-1/3}. The proof combines three components: a limiting absorption principle via Mourre theory with the conjugate operator A satisfying iA = NP − P*N (Section 2 and Appendix A), full asymptotic expansions of the free and perturbed resolvent at the degenerate threshold 0 and the second threshold 16, including a resonance classification in weighted ℓ² spaces (Theorems 1.7 and 1.8), and Van der Corput estimates for the four kernel components of Stone's formula (Sections 3 and 4).

Significance. If the conditional results are accepted, this is a significant contribution to discrete dispersive estimates: it is, to my knowledge, the first limiting absorption principle and threshold analysis for a higher-order discrete Schrödinger operator with potentials, and it provides a complete resonance classification at both thresholds of Δ². The free decay rate is derived parameter-free and its sharpness is proved by a rigorous Knapp-type argument rather than asserted; the β-thresholds in Theorem 1.2 are exactly matched to the order of the resolvent expansions in Lemma 5.1, which is a sign of internal consistency. The proofs are detailed and largely self-contained, with the Mourre-theory input from [30] and the discrete LAP input from [33] clearly identified. The principal weakness is the conditional nature of Theorem 1.2; this is acknowledged in Remark 1.3, but it is not reflected in the abstract.

major comments (3)
  1. [Abstract; Theorem 1.2; Corollary 2.5] The abstract announces the decay estimate for H = Δ² + V under 'suitable decay conditions on V' without stating the spectral hypothesis, but the result actually proved in Theorem 1.2 is conditional on the assumption that H has no positive eigenvalues in I=(0,16). This hypothesis is load-bearing: it is used in Corollary 2.5 (where the invertibility of M±(µ) is deduced from the absence of eigenvalues in I and Theorem 2.4) to obtain the resolvent identity (2.11), which in turn feeds the expansions in Theorem 1.8 and all the kernel estimates in Section 4. If an admissible potential had an eigenvalue at µ₀⁴ ∈ (0,16), the expansion of (M±(µ))^{-1} would not be available near µ₀ and the uniform |t|^{-1/4} bound would not follow from the given proof. The abstract and the announcement in Section 1.1 should therefore state the no-positive-eigenvalue hypothesis explicitly, so that the advertised claim matches the theorem.
  2. [Remark 1.3; Corollary 2.5] The no-positive-eigenvalue hypothesis is not verified for any potential in the allowed class beyond V ≡ 0 and the δ-potentials treated in [22]; Remark 1.3 explicitly says that 'more studies are needed' to establish the absence of positive eigenvalues for higher-order discrete operators, and the resonance examples in Section 1.2 are not checked for embedded eigenvalues. Since the invertibility of M±(µ) for every µ ∈ (0,2) is equivalent, through the resolvent identity, to the absence of eigenvalues at µ⁴, the advertised statement 'under suitable decay conditions on V' is stronger than what is proved. I recommend that the authors either (a) prove the absence of positive eigenvalues for a natural subclass of the allowed potentials (e.g., sign-definite potentials, potentials of sufficiently small norm, or compactly supported potentials), or (b) keep the conditional form but add an explicit paragraph collecting all cases where the hypothesis is known to hold, and state the theorem in exactly that conditional form in the abstract.
  3. [Section 4 (opening); Eq. (1.13)] The beam estimate (1.13), one of the two headline results, is not proved. The paper states (Section 1.3 and the opening of Section 4) that it suffices to prove (1.12) for e^{-itH}P_ac(H) and that (1.13) 'follows similarly' for e^{-it√H}P_ac(H), because the difference between (1.14) and (1.15) lies only in the power of µ in the exponent. The change of phase from tµ⁴ to tµ² is not purely notational for the stationary-phase analysis: for the beam, the µ³ factor cancels the µ^{-3} singularity of the free resolvent at µ=0, while the |t|^{-1/3} rate is produced by interior inflection points of the dispersion relation (the s=±2 cases of the free phase 2−2cosθ), a regime that does not occur in the |t|^{-1/4} analysis of Section 4.2. Since (1.13) is claimed for the full perturbed operator, please supply the detailed proof, or at least a complete reduction of each kernel component K±j for the phase tµ², including the treatment of the interior region [µ₀, 2−µ₀].
minor comments (5)
  1. [Theorem 4.1(iii)] The displayed threshold conditions in (4.5) read '11, 0 is the resonance of H' and '15, 0 is the eigenvalue of H'; both should refer to the point 16, since K±3 is the component localized near µ=2 and the surrounding subsection is devoted to the threshold 16.
  2. [Abstract; Section 1.1; Section 2.2] There are several typos: the Abstract has 'a complete characterizations' (should be 'a complete characterization'), Section 1.1 has 'mathematics physics' (should be 'mathematical physics'), and Section 2.2 has 'Theroem 2.4' (should be 'Theorem 2.4').
  3. [Lemma 5.1] The differentiability claims ('in the same sense, the (5.1) can be differentiated N+4 times in µ'; similarly 'N+2 times' for (5.3)) are incomplete as stated: each differentiation multiplies the kernel by powers of |n−m|, so the required weight s must be larger for the differentiated expansion, and the size of the remainder after k derivatives should be stated. This matters because the bound (1.27) for the remainders in Theorem 1.8 involves ∂µΓ, so the weight and remainder statements in Lemma 5.1 should be precise.
  4. [Lemma 5.2(3)] The proof of negative definiteness of the quadratic form (5.46)–(5.48) is terse: the inequalities ⟨g₁,h₁⟩ ≤ 1/4 and ⟨g₂,h₂⟩ ≤ ∥v′∥⁴/64 are asserted as consequences of (5.41) without derivation, and the strictness caveat 'both inequalities are strict if ⟨h₂,g₁⟩≠0' is used in a crucial way. Please expand this step to make the '⊆' direction transparent.
  5. [Definition 1.1; Section 1.2] In Definition 1.1(II), the resonance class at 16 allows solutions in W1/2(Z) that are not in ℓ²(Z); since W1/2(Z) = ∩_{s>1/2}ℓ^{2,−s} contains non-ℓ² functions (e.g., constants), the distinction between resonance and eigenvalue at 16 is meaningful, but a short remark reminding the reader of the inclusion chain ℓ² ⊆ W₀ ⊆ W1/2 ⊆ W3/2 would prevent confusion.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: decay estimates follow from Stone's formula, resolvent expansions, and Van der Corput estimates; the no-eigenvalue assumption is an explicit conditional hypothesis, not a derived conclusion smuggled in.

full rationale

The paper's derivation chain is self-contained: the |t|^{-1/4} and |t|^{-1/3} estimates are obtained from Stone's formula (1.14)-(1.15), the resolvent identity (1.17)/(2.11), the asymptotic expansions of (M^±(µ))^{-1} in Theorem 1.8, and oscillatory integral estimates via Van der Corput. The desired decay rates are not assumed anywhere; they emerge from the phase analysis of e^{-itµ^4} and e^{-itµ^2} combined with kernel estimates. No parameter is fitted to the target decay law. The free case sharpness is proved independently through a Knapp counterexample and the Keel-Tao abstract Strichartz theorem. The only potentially sensitive point is the hypothesis that H has no positive eigenvalues in I=(0,16), used in Corollary 2.5 to ensure invertibility of M^±(µ); but this is explicitly stated as an assumption in Theorem 1.2, and Remark 1.3 openly acknowledges that absence of positive eigenvalues is not established for the general potential class, citing only the δ-potential case [22] and noting that more studies are needed. That is a limitation of the theorem's applicability, not a circular step. Citations [33], [30], and [52] supply standard or independently checkable ingredients (free resolvent kernels, Mourre theory, and a Taylor-type expansion lemma) rather than the target estimate, so they do not make the argument circular. No self-citation chain forces the conclusion.

Assumptions & free parameters 0 free parameters · 5 assumptions · 0 invented entities

The central claim rests on standard oscillatory integral and spectral theory, on the stated potential decay and no-eigenvalue hypotheses, and on the free resolvent analysis. No fitted constants appear; the decay exponents are consequences of phase degeneracies.

assumptions (5)
  • standard math Van der Corput lemma and Keel-Tao Strichartz criterion
    Used to bound oscillatory integrals and transfer decay to Strichartz estimates; cited, not proved.
  • standard math Mourre commutator theory, including Jensen-Mourre-Perry [30]
    Basis for the limiting absorption principle; invoked in Section 2 and Appendix A.
  • standard math Free resolvent kernel for the one-dimensional discrete Laplacian ([33, Lemma 2.1])
    Starting point for the free bi-Laplacian resolvent formula (2.8).
  • domain assumption Real-valued potential with |V(n)| ≤ C ⟨n⟩^{-β} and β above the stated thresholds
    Defines the admissible class; decay thresholds are needed for the resolvent expansions.
  • domain assumption No positive eigenvalues of H in the interval (0,16)
    Used to prove invertibility of M^±(µ) in Corollary 2.5; not proved for the general class.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Decay estimates for discrete bi-Laplace operators with potentials on the lattice $\mathbb{Z}$." pith.science (2026). https://pith.science/paper/4LGZRHIE

@misc{pith2026250623119,
  author       = {Pith},
  title        = {Pith review of: Decay estimates for discrete bi-Laplace operators with potentials on the lattice $\mathbbZ$},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/4LGZRHIE}},
  note         = {Machine review of arXiv:2506.23119}
}
abstract

It is known that the discrete Laplace operator $\Delta$ on the lattice $\mathbb{Z}$ satisfies the following sharp time decay estimate: $$\big\|e^{it\Delta}\big\|_{\ell^1\rightarrow\ell^{\infty}}\lesssim|t|^{-\frac{1}{3}},\quad t\neq0,$$ which is slower than the usual $ O(|t|^{-\frac{1}{2}})$ decay in the continuous case on $\mathbb{R}$. However, this paper shows that the discrete bi-Laplacian $\Delta^2$ on $\mathbb{Z}$ actually exhibits the same sharp decay estimate $|t|^{-\frac{1}{4}}$ as its continuous counterpart. In view of the free decay estimate, we further investigate the discrete bi-Schr\"{o}dinger operators of the form $H=\Delta^2+V$ on the lattice space $\ell^2(\mathbb{Z})$, where $V$ is a class of real-valued decaying potentials on $\mathbb{Z}$. First, we establish the limiting absorption principle for $H$, and then derive the full asymptotic expansions of the resolvent of $H$ near the thresholds $0$ and $16$, including resonance cases. In particular, we provide a complete characterizations of the different resonance types in $\ell^2$-weighted spaces. Based on these results above, we establish the following sharp $\ell^1-\ell^{\infty}$ decay estimates for all different resonances types of $H$ under suitable decay conditions on $V$: $$\big\|e^{-itH}P_{ac}(H)\big\|_{\ell^1\rightarrow\ell^{\infty}}\lesssim|t|^{-\frac{1}{4}},\quad t\neq0,$$ where $P_{ac}(H)$ denotes the spectral projection onto the absolutely continuous spectrum space of $H$. Additionally, the decay estimates for the evolution flow of discrete beam equation are also derived: $$\|{\cos}(t\sqrt H)P_{ac}(H)\|_{\ell^1\rightarrow\ell^{\infty}}+\Big\|\frac{{\sin}(t\sqrt H)}{t\sqrt H}P_{ac}(H)\Big\|_{\ell^1\rightarrow\ell^{\infty}}\lesssim|t|^{-\frac{1}{3}},\quad t\neq0.$$

Figures

Figures reproduced from arXiv: 2506.23119 by the authors.

Figure 1
Figure 1. The map θ(ω) from C \ [0, 4] to D. (ii) If λ ∈ (−∞, 0), then sinθ(λ) = −i r −λ + λ2 4 = i e −iθ(λ) − e iθ(λ) 2 . (2.7) Lemma 2.3. For µ ∈ (0, 2), the kernel of R ± 0 (µ 4 ) is given by R ± 0 (µ 4 , n, m) = 1 4µ3  ± ia1(µ)e ∓iθ+|n−m| + a2(µ)e b(µ)|n−m|  := 1 4µ3A ±(µ, n, m), (2.8) where θ+ := θ+(µ 2 ) satisfies 2 − 2cosθ+ = µ 2 with θ+ ∈ (−π, 0) and a1(µ) = 1 q 1 − µ2 4 , a2(µ) = −1 q 1 + µ2 4 , b(µ) = ln 1 + µ 2 2… view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

56 extracted references · 54 canonical work pages

  1. [30]

    Jensen, E

    A. Jensen, E. Mourre and P. Perry, Multiple commutator estimates and resolvent smoothness in quantum scattering theory, Ann. Inst. H. Poincar´ e Phys. Th´ eor.41 (1984), no. 2, 207–225

  2. [33]

    A. I. Komech, E. A. Kopylova and M. Kunze, Dispersive estimates for 1D discrete Schr¨ odinger and Klein-Gordon equations, Appl. Anal. 85 (2006), no. 12, 1487–1508

  3. [22]

    Hiroshima and J

    F. Hiroshima and J. L˝ orinczi, The spectrum of non-local discrete Schr¨ odinger operators with a δ- potential, Pac. J. Math. Ind. 6 (2014), Art. 7, 6pp

  4. [1]

    Aizenman and S

    M. Aizenman and S. Warzel. Random operators, Disorder effects on quantum spectra and dynamics, Grad. Stud. Math., 168, American Mathematical Society, Providence, RI, 2015, xiv+326pp

  5. [2]

    W. O. Amrein, A. Boutet de Monvel and V. Georgescu, C0-groups, commutator methods and spectral theory of N -body Hamiltonians, Birkh¨ auser, 1996

  6. [3]

    Agmon, Spectral properties of Schr¨ odinger operators and scattering theory, Ann

    S. Agmon, Spectral properties of Schr¨ odinger operators and scattering theory, Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4) 2 (1975), no. 2, 151–218

  7. [4]

    Boutet de Monvel and J

    A. Boutet de Monvel and J. Sahbani, On the spectral properties of discrete Schr¨ odinger operators, C. R. Acad. Sci. Paris S´ er. I Math.326 (1998), no. 9, 1145–1150

  8. [5]

    Boutet de Monvel and J

    A. Boutet de Monvel and J. Sahbani, On the spectral properties of discrete Schr¨ odinger operators: the multi-dimensional case, Rev. Math. Phys. 11 (1999), no. 9, 1061–1078

Show all 56 references
  1. [6]

    Bellissard and H

    J. Bellissard and H. Schulz-Baldes, Scattering theory for lattice operators in dimension d ≥ 3, Rev. Math. Phys. 24 (2012), no.8, 1250020, 51pp

  2. [7]

    Cheng, S

    H. Cheng, S. Huang, T. Huang and Q. Zheng, Pointwise estimates for the fundamental solu- tions of higher order Schr¨ odinger equations in odd dimensions I: low dimensional case, Revisited, https://arxiv.org/abs/2401.04969

  3. [8]

    Cheng, S

    H. Cheng, S. Huang, T. Huang and Q. Zheng, Pointwise estimates for the fundamental solu- tions of higher order Schr¨ odinger equations in odd dimensions II: high dimensional case, Revisited, https://arxiv.org/abs/2409.00117

  4. [9]

    M. Chen, P. Li, A. Soffer, and X. Yao, Decay estimates for Beam equations with potential in dimension three, J. Funct. Anal. 288 (2025), no. 1, Paper No. 110671, 54pp

  5. [10]

    Cuccagna and M

    S. Cuccagna and M. Tarulli. On asymptotic stability of standing waves of discrete Schr¨ odinger equation in Z. SIAM J. Math. Anal. 41 (2009), no. 3, 861–885

  6. [11]

    Cuccagna, Lp continuity of wave operators in Z, J

    S. Cuccagna, Lp continuity of wave operators in Z, J. Math. Anal. Appl. 354 (2009), no. 2, 594–605

  7. [12]

    M. S. `Eskina. The scattering problem for partial-difference equations. Math. Phys. (1967), no. 3, 248–273

  8. [13]

    Egorova, E

    I. Egorova, E. Kopylova and G. Teschl, Dispersion estimates for one-dimensional discrete Schr¨ odinger and wave equations, J. Spectr. Theory. 5 (2015), no. 4, 663–696

  9. [14]

    Erdo˘ gan, W

    M. Erdo˘ gan, W. Green and E. Toprak, On the fourth order Schr¨ odinger equation in three dimensions: dispersive estimates and zero energy resonances, J. Differential Equations , 271 (2021), 152–185

  10. [15]

    Erdo˘ gan and W

    M. Erdo˘ gan and W. Schlag, Dispersive estimates for Schr¨ odinger operators in the presence of a reso- nance and/or an eigenvalue at zero energy in dimension three. I, Dyn. Partial Differ. Equ. , 1 (2004), no. 4, 359–379

  11. [16]

    H. Feng, A. Soffer, Z. Wu and X. Yao, Decay estimates for higher-order elliptic operators, Trans. Amer. Math. Soc. , 373 (2020), no. 4, 2805–2859

  12. [17]

    H. Feng, A. Soffer and X. Yao, Decay estimates and Strichartz estimates of fourth-order Schr¨ odinger operator, J. Funct. Anal. , 274 (2018), no. 2, 605–658

  13. [18]

    Georgescu, C

    V. Georgescu, C. G´ erard and J. S. Møller, Commutators, C0-semigroups and resolvent estimates, J. Funct. Anal. 216 (2004), no. 2, 303–361. 64 SISI HUANG AND XIAOHUA YAO

  14. [19]

    Goldberg and W.R

    M. Goldberg and W.R. Green, Dispersive estimates for higher dimensional Schr¨ oodinger operators with threshold eigenvalues I: The odd dimensional case, J. Funct. Anal. , 269 (2015), no. 3, 633–682

  15. [20]

    Goldberg and W.R

    M. Goldberg and W.R. Green, Dispersive estimates for higher dimensional Schr¨ odinger operators with threshold eigenvalues II. The even dimensional case, J. Spectr. Theory, 7 (2017), no. 1, 33–86

  16. [21]

    Hayashi, Y

    Y. Hayashi, Y. Higuchi, Y. Nomura and O. Ogurisu, On the number of discrete eigenvalues of a discrete Schr¨ odinger operator with a finitely supported potential, Lett. Math. Phys. 106 (2016), no. 11, 1465–1478

  17. [23]

    Higuchi, T

    Y. Higuchi, T. Matsumoto and O. Ogurisu, On the spectrum of a discrete Laplacian on Z with finitely supported potential, Linear Multilinear Algebra. 59 (2011), no. 8, 917–927

  18. [24]

    Hiroshima, Z

    F. Hiroshima, Z. Muminov and U. Kuljanov, Threshold of discrete Schr¨ odinger operators with delta potentials on n-dimensional lattice, Linear Multilinear Algebra 70 (2022), no. 5, 919–954

  19. [25]

    Hiroshima, I

    F. Hiroshima, I. Sasaki, T. Shirai and A. Suzuki, Note on the spectrum of discrete Schr¨ odinger oper- ators, Pac. J. Math. Ind. 4B (2012), 105–108

  20. [26]

    Ito and A

    K. Ito and A. Jensen, A complete classification of threshold properties for one-dimensional discrete Schr¨ odinger operators,Rev. Math. Phys. 27 (2015), no. 1, 1550002, 45pp

  21. [27]

    Isozaki and E

    H. Isozaki and E. Korotyaev, Inverse problems, trace formulae for discrete Schr¨ odinger operators,Ann. Henri Poincar´ e13 (2012), no. 4, 751–788

  22. [28]

    Isozaki and H

    H. Isozaki and H. Morioka, A Rellich type theorem for discrete Schr¨ odinger operators. Inverse Probl. Imaging 8 (2014), no. 2, 475–489

  23. [29]

    Jensen and T

    A. Jensen and T. Kato, Spectral properties of Schr¨ odinger operators and time-decay of the wave functions, Duke Math. J. 46 (1979), no. 3, 583–611

  24. [31]

    Jensen and G

    A. Jensen and G. Nenciu, A unified approach to resolvent expansions at thresholds, Rev. Math. Phys. 13 (2001), no. 6, 717–754

  25. [32]

    Journ´ e, A

    J.-L. Journ´ e, A. Soffer and C.D. Sogge, Decay estimates for Schr¨ odinger operators,Comm. Pure Appl. Math. 44 (1991), no. 5, 573–604

  26. [34]

    A. I. Komech, E. A. Kopylova and B. R. Vainberg, On dispersive properties of discrete 2D Schr¨ odinger and Klein-Gordon equations, J. Funct. Anal. 254 (2008), no. 8, 2227–2254

  27. [35]

    Korotyaev and J.S

    E.L. Korotyaev and J.S. Møller, Weighted estimates for the Laplacian on the cubic lattice, Ark. Mat., 57 (2019), no. 2, 397–428

  28. [36]

    Kr¨ uger, On the existence of embedded eigenvalues,J

    H. Kr¨ uger, On the existence of embedded eigenvalues,J. Math. Anal. Appl. 395 (2012), no. 2, 776–787

  29. [37]

    Keel and T

    M. Keel and T. Tao, Endpoint Strichartz estimates, Amer. J. Math. 120 (1998), no. 5, 955–980

  30. [38]

    Liu, Criteria for eigenvalues embedded into the absolutely continuous spectrum of perturbed Stark type operators, J

    W. Liu, Criteria for eigenvalues embedded into the absolutely continuous spectrum of perturbed Stark type operators, J. Funct. Anal. 276 (2019), no. 9, 2936–2967

  31. [39]

    Liu, Irreducibility of the Fermi variety for discrete periodic Schr¨ odinger operators and embedded eigenvalues, Geom

    W. Liu, Irreducibility of the Fermi variety for discrete periodic Schr¨ odinger operators and embedded eigenvalues, Geom. Funct. Anal. 32 (2022), no. 1, 1–30

  32. [40]

    W. Liu, R. Matos and J. N. Treuer, Sharp decay rate for eigenfunctions of perturbed periodic schr¨ odinger operators, https://arxiv.org/abs/2409.10387

  33. [41]

    Marklof, Arithmetic Quantum Chaos, Academic Press, Oxford, (2006), 212-221

    J. Marklof, Arithmetic Quantum Chaos, Academic Press, Oxford, (2006), 212-221

  34. [42]

    Mandich, The limiting absorption principle for the discrete Wigner–von Neumann operator, J

    M.-A. Mandich, The limiting absorption principle for the discrete Wigner–von Neumann operator, J. Funct. Anal. 272 (2017), no. 6, 2235–2272

  35. [43]

    Mandich, Sub-exponential decay of eigenfunctions for some discrete Schr¨ odinger operators, J

    M.-A. Mandich, Sub-exponential decay of eigenfunctions for some discrete Schr¨ odinger operators, J. Spectr. Theory 9 (2019), no. 1, 21–77

  36. [44]

    Mourre, Absence of singular continuous spectrum for certain selfadjoint operators, Comm

    E. Mourre, Absence of singular continuous spectrum for certain selfadjoint operators, Comm. Math. Phys. 78 (1980/81), no. 3, 391–408

  37. [45]

    Mourre, Operateurs conjugu´ es et propri´ et´ es de propagation,Comm

    E. Mourre, Operateurs conjugu´ es et propri´ et´ es de propagation,Comm. Math. Phys. 91 (1983), no. 2, 279–300

  38. [46]

    Mi and Y

    Y. Mi and Y. Zhao, Dispersive estimates for periodic discrete one-dimensional Schr¨ odinger operators, Proc. Amer. Math. Soc. 150 (2022), no. 1, 267–277

  39. [47]

    ¨Ochsner, Classical Beam Theories of Structural Mechanics, Springer International Publishing, (2021), 7-66

    A. ¨Ochsner, Classical Beam Theories of Structural Mechanics, Springer International Publishing, (2021), 7-66. DECAY ESTIMATES FOR DISCRETE BI-SCHR ¨ODINGER OPERATORS WITH RESONANT THRESHOLDS 65

  40. [48]

    D. E. Pelinovsky and A. Stefanov, On the spectral theory and dispersive estimates for a discrete Schr¨ odinger equation in one dimension,J. Math. Phys. 49 (2008), no. 11, 113501, 17pp

  41. [49]

    Reed and B

    M. Reed and B. Simon, Methods of modern mathematical physics. IV. Analysis of operators, Academic Press [Harcourt Brace Jovanovich, Publishers], New York-London, 1978, xv+396 pp

  42. [50]

    Rodnianski and W

    I. Rodnianski and W. Schlag, Time decay for solutions of Schr¨ odinger equations with rough and time-dependent potentials, Invent. Math. , 155 (2004), no. 3, 451–513

  43. [51]

    Stefanov and P

    A. Stefanov and P. G. Kevrekidis, Asymptotic behaviour of small solutions for the discrete nonlinear Schr¨ odinger and Klein-Gordon equations,Nonlinearity 18 (2005), no. 4, 1841–1857

  44. [52]

    Soffer, Z

    A. Soffer, Z. Wu and X. Yao, Decay estimates for bi-Schr¨ odinger operators in dimension one, Ann. Henri Poincar´ e23 (2022), no. 8, 2683–2744

  45. [53]

    Tao, Nonlinear dispersive equations

    T. Tao, Nonlinear dispersive equations. Local and global analysis CBMS Reg. Conf. Ser. Math., 106 Published for the Conference Board of the Mathematical Sciences, Washington, DC; by the American Mathematical Society, Providence, RI, 2006. xvi+373 pp

  46. [54]

    Schlag, Dispersive estimates for Schr¨ odinger operators: a survey Mathematical aspects of nonlinear dispersive equations, Ann

    W. Schlag, Dispersive estimates for Schr¨ odinger operators: a survey Mathematical aspects of nonlinear dispersive equations, Ann. of Math. Stud. 163 (2007), 255-285

  47. [55]

    E. M. Stein, Harmonic analysis: real-variable methods, orthogonality, and oscillatory integrals , vol- ume 43 of Princeton Mathematical Series , Princeton University Press, Princeton, NJ, 1993, With the assistance of Timothy S. Murphy, Monographs in Harmonic Analysis, III

  48. [56]

    Shaban and B

    W. Shaban and B. Vainberg, Radiation conditions for the difference Schr¨ odinger operators, Appl. Anal. 80 (2001), no. 3-4, 525–556. Sisi Huang, Department of Mathematics, Central China Normal University, Wuhan, 430079, P.R. China Email address : hss@mails.ccnu.edu.cn Xiaohua ...

Pith tools

Reviewed August 6, 2026 · model on record in the stance chip above.