pith. sign in

arxiv: 2411.17036 · v6 · submitted 2024-11-26 · 🧮 math-ph · math.AP· math.MP· math.PR· nlin.PS· nlin.SI

Law of Large Numbers and Central Limit Theorem for random sets of solitons of the focusing nonlinear Schr\"odinger equation

Pith reviewed 2026-05-23 17:42 UTC · model grok-4.3

classification 🧮 math-ph math.APmath.MPmath.PRnlin.PSnlin.SI
keywords soliton gaslaw of large numberscentral limit theoremfocusing nonlinear Schrödinger equationZakharov-Shabat operatorrandom eigenvaluesnorming constantsinverse scattering
0
0 comments X

The pith

Finite random soliton solutions converge in probability and distribution to a deterministic soliton gas limit of the focusing nonlinear Schrödinger equation.

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

The paper examines configurations of N solitons whose eigenvalues are drawn i.i.d. from a fixed compact distribution in the complex plane, while norming constants are obtained by smooth deterministic interpolation of those eigenvalues. The expected spectral measure determines, through the inverse scattering transform, a limiting solution ψ_∞ that can be viewed as a soliton gas. On any compact set in the (x,t) plane the random finite-N field ψ_N differs from this limit by an amount that vanishes in probability (law of large numbers) and, after scaling by √N, converges in distribution to a centered Gaussian process whose covariance functions are computed explicitly. The same statements hold for the intensity |ψ_N|^2.

Core claim

When the eigenvalues λ_j are i.i.d. random variables with compact support and the norming constants are fixed smooth functions of the λ_j, the expectation of the associated random spectral measure identifies a deterministic solution ψ_∞ of the focusing NLS via the Zakharov-Shabat inverse problem; moreover, the centered fields √N(ψ_N - ψ_∞) and √N(|ψ_N|^2 - |ψ_∞|^2) converge in law to Gaussian processes on compact space-time sets, with explicit two-point correlation functions.

What carries the argument

The Zakharov-Shabat inverse spectral problem applied to the expectation of the random measure whose atoms are the random eigenvalues and their interpolated norming constants.

If this is right

  • The soliton gas ψ_∞ is the mean-field limit of the random N-soliton ensemble.
  • Fluctuations around the limit are Gaussian and their covariance is determined by the eigenvalue density alone.
  • The convergence statements are uniform on compact subsets of space-time, so local statistics are well-defined.
  • Explicit correlation functions give access to the second-moment structure of the soliton gas.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The same spectral-measure approach may produce fluctuation theorems for other integrable equations whose scattering data admit analogous random ensembles.
  • Numerical sampling of large-N soliton gases can be used to test the predicted Gaussian covariance directly.
  • The result supplies a microscopic justification for kinetic models of soliton gases that treat the gas as a deterministic density with small random corrections.

Load-bearing premise

Norming constants are produced by a fixed smooth map from the random eigenvalues, so randomness enters solely through the eigenvalue distribution.

What would settle it

A direct Monte-Carlo computation showing that the empirical variance of ψ_N(x,t) - ψ_∞(x,t) fails to decay proportionally to 1/N for large N at a fixed interior point (x,t).

Figures

Figures reproduced from arXiv: 2411.17036 by Joseph Najnudel, Ken D. T-R McLaughlin, Manuela Girotti, Tamara Grava.

Figure 1
Figure 1. Figure 1: A schematic depiction of the setting of Theorem 2.6. 2. M has boundary values M+(z) and M−(z) on γ which satisfy the jump relation (2.16) M+(z) = M−(z)J(z; x, t), z ∈ γ . 3. M satisfies the normalization condition (2.17) M(z) = I + O ( 1 z ) , as z → ∞. Remark 2.4. Note that, thanks to the eigenvalues {λk}’s being i.i.d. and the interpolation (2.8), the averaged jump matrix J does not depend on N. Indeed, … view at source ↗
read the original abstract

We study a random configuration of $N$ soliton solutions $\psi_N(x,t;\boldsymbol{\lambda})$ of the cubic focusing Nonlinear Schr\"odinger (fNLS) equation in one space dimension. The $N$ soliton solutions are parametrized by $2N$ complex numbers $(\boldsymbol{\lambda}, \boldsymbol{c})$ where $\boldsymbol{\lambda}\in\mathbb{C}_+^N$ are the eigenvalues of the Zakharov-Shabat linear operator, and $ \boldsymbol{c}\in\mathbb{C}^N\backslash \{0\}$ are the norming constants of the corresponding eigenfunctions. The randomness is obtained by choosing the complex eigenvalues to be i.i.d. random variables sampled from a probability distribution with compact support in the complex plane. The corresponding norming constants are interpolated by a smooth function of the eigenvalues. Then we consider the expectation of the random measure associated to this random spectral data. Such expectation uniquely identifies, via the Zakharov-Shabat inverse spectral problem, a solution $\psi_\infty(x,t)$ of the fNLS equation. This solution can be interpreted as a soliton gas solution. We prove a Law of Large Numbers and a Central Limit Theorem for the differences $\psi_N(x,t;\boldsymbol{\lambda})-\psi_\infty(x,t)$ and $|\psi_N(x,t;\boldsymbol{\lambda})|^2-|\psi_\infty(x,t)|^2$ when $(x,t)$ are in a compact set of $\mathbb R\times\mathbb R^+$; we additionally compute the correlation functions.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The manuscript studies random N-soliton solutions ψ_N of the focusing NLS equation, with eigenvalues chosen i.i.d. from a compactly supported probability distribution in the upper half-plane and norming constants obtained via smooth deterministic interpolation of those eigenvalues. The limiting object ψ_∞ is constructed by applying the Zakharov-Shabat inverse spectral problem to the expected spectral measure; the paper proves a law of large numbers and central limit theorem for the differences ψ_N(x,t;λ) − ψ_∞(x,t) and |ψ_N|^2 − |ψ_∞|^2 uniformly on compact subsets of R × R^+, together with explicit correlation functions.

Significance. If the stated results hold, the work supplies a rigorous probabilistic justification for the soliton-gas concept in integrable systems by combining empirical-measure convergence with continuity of the inverse spectral map. The explicit computation of correlation functions is a concrete strength that enables quantitative fluctuation analysis. This framework is likely to be useful for modeling random soliton ensembles in nonlinear optics and fluid dynamics.

major comments (2)
  1. [Abstract, §2] Abstract and §2 (construction of ψ_∞): the claim that the limiting solution is uniquely identified by the expected spectral measure relies on the continuity of the Zakharov-Shabat map on the compact (x,t) sets; the manuscript must explicitly verify that the smooth interpolation of norming constants preserves the required analyticity and boundedness so that the map remains continuous under weak convergence of measures.
  2. [CLT statement and proof] Theorem on CLT (presumably §4): the variance in the central limit theorem is computed from the limiting measure, but the proof sketch does not indicate how the compact support of the eigenvalue distribution yields uniform integrability or moment bounds needed to interchange limits and the inverse spectral transform; a concrete estimate controlling the remainder in the reconstruction formula is required.
minor comments (2)
  1. [§1] Notation for the random vector λ should be clarified when it appears both as the full N-tuple and in the limiting measure.
  2. [Abstract] The statement that the norming constants are 'interpolated by a smooth function' would benefit from an explicit formula or reference to the interpolation operator used.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading, positive assessment, and constructive suggestions. We address the two major comments point by point below and will incorporate the requested clarifications into the revised manuscript.

read point-by-point responses
  1. Referee: [Abstract, §2] Abstract and §2 (construction of ψ_∞): the claim that the limiting solution is uniquely identified by the expected spectral measure relies on the continuity of the Zakharov-Shabat map on the compact (x,t) sets; the manuscript must explicitly verify that the smooth interpolation of norming constants preserves the required analyticity and boundedness so that the map remains continuous under weak convergence of measures.

    Authors: We agree that an explicit verification strengthens the argument. In the revised version we will insert a short lemma in §2 establishing that the smooth deterministic interpolation of the norming constants, combined with the compact support of the eigenvalue distribution, preserves the necessary analyticity in the upper half-plane and the uniform boundedness conditions. These properties ensure continuity of the Zakharov-Shabat inverse spectral map under weak convergence of the empirical measures on the indicated compact (x,t) sets. revision: yes

  2. Referee: [CLT statement and proof] Theorem on CLT (presumably §4): the variance in the central limit theorem is computed from the limiting measure, but the proof sketch does not indicate how the compact support of the eigenvalue distribution yields uniform integrability or moment bounds needed to interchange limits and the inverse spectral transform; a concrete estimate controlling the remainder in the reconstruction formula is required.

    Authors: We thank the referee for this observation. The compact support of the eigenvalue distribution supplies the required uniform integrability and moment bounds. In the revised proof of the CLT we will add an explicit remainder estimate in the reconstruction formula that quantifies the error arising from the difference between the empirical and limiting measures; the estimate relies directly on the boundedness of the support to justify interchanging the limit and the inverse spectral transform, thereby confirming that the variance is indeed determined by the limiting measure. revision: yes

Circularity Check

0 steps flagged

No significant circularity identified

full rationale

The derivation introduces randomness externally via i.i.d. eigenvalues drawn from a fixed compactly supported distribution, with norming constants obtained by a deterministic smooth interpolation of those eigenvalues. The limiting object ψ_∞ is then constructed from the expectation of the resulting random spectral measure by applying the Zakharov-Shabat inverse spectral problem; this construction is independent of the finite-N realizations. The claimed LLN and CLT are standard consequences of empirical-measure convergence plus continuity of the inverse map on compact (x,t) sets, with no reduction of the target quantities to fitted parameters, self-definitions, or load-bearing self-citations. The correlation functions are likewise obtained directly from the same limiting measure. The setup is therefore self-contained against external probabilistic and analytic benchmarks.

Axiom & Free-Parameter Ledger

2 free parameters · 1 axioms · 1 invented entities

The construction rests on the Zakharov-Shabat spectral theory and inverse problem (standard in the domain) plus two modeling choices that are not derived from first principles: the choice of probability distribution on eigenvalues and the smooth interpolation rule for norming constants.

free parameters (2)
  • probability distribution on eigenvalues
    i.i.d. sampling from a distribution with compact support in the complex plane; this distribution is an external modeling choice.
  • smooth interpolation function for norming constants
    The map from eigenvalues λ to norming constants c is assumed to be a fixed smooth function; this choice determines the random measure.
axioms (1)
  • domain assumption The Zakharov-Shabat inverse spectral problem uniquely recovers a solution of the fNLS equation from the spectral data (eigenvalues and norming constants).
    Invoked to define both the random solutions ψ_N and the limiting soliton gas ψ_∞ from the expectation of the random measure.
invented entities (1)
  • soliton gas solution ψ_∞ no independent evidence
    purpose: Deterministic limiting object obtained from the expectation of the random spectral measure.
    Defined via the expectation; no independent physical evidence supplied in the abstract.

pith-pipeline@v0.9.0 · 5844 in / 1528 out tokens · 47274 ms · 2026-05-23T17:42:11.118000+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Asymptotic Scattering Relation for the Toda Lattice

    math-ph 2025-03 unverdicted novelty 6.0

    The thermal Toda lattice is modeled as quasiparticles whose locations satisfy an asymptotic scattering relation derived from eigenvector properties of the Lax matrix.

Reference graph

Works this paper leans on

53 extracted references · 53 canonical work pages · cited by 1 Pith paper

  1. [1]

    Soliton-mean field interaction in Korteweg-de Vries dispersive hydrodynamics

    M. J. Ablowitz, J. T. Cole, G. A. El, M. A. Hoefer, and X.-D. Luo. “Soliton-mean field interaction in Korteweg-de Vries dispersive hydrodynamics”. In:Stud. Appl. Math.151.3 (2023), pp. 795–856

  2. [2]

    B ERTOLA , T

    M. Bertola, T. Grava, and G. Orsatti. “¯∂-problem for focusing nonlinear Schrödinger equation and soliton shielding”. In:arXiv:2409.14825 (2024)

  3. [3]

    Soliton Shielding of the Focusing Nonlinear Schrödinger Equation

    M. Bertola, T. Grava, and G. Orsatti. “Soliton Shielding of the Focusing Nonlinear Schrödinger Equation”. In:Phys. Rev. Lett.130.12 (2023), p. 127201

  4. [4]

    Maximal amplitudes of finite-gap solutions for the focusing Nonlinear Schrödinger Equation

    M. Bertola and A. Tovbis. “Maximal amplitudes of finite-gap solutions for the focusing Nonlinear Schrödinger Equation”. In:Comm. Math. Phys.354 (2017), pp. 525–547

  5. [5]

    Far-field asymptotics for multiple-pole solitons in the large-order limit

    D. Bilman, R. Buckingham, and D.-S. Wang. “Far-field asymptotics for multiple-pole solitons in the large-order limit”. In:J. Differential Equations297 (2021), pp. 320–369

  6. [6]

    Extreme superposition: rogue waves of infinite order and the Painlevé-III hierarchy

    D. Bilman, L. Ling, and P. D. Miller. “Extreme superposition: rogue waves of infinite order and the Painlevé-III hierarchy”. In:Duke Math. J.169.4 (2020), pp. 671–760

  7. [7]

    A robust inverse scattering transform for the focusing nonlinear Schrödinger equation

    D. Bilman and P. D. Miller. “A robust inverse scattering transform for the focusing nonlinear Schrödinger equation”. In:Comm. Pure Appl. Math.72.8 (2019), pp. 1722–1805

  8. [8]

    Inverse scattering transform for the focusing nonlinear Schrödinger equation with nonzero boundary conditions

    G. Biondini and G. Kovačič. “Inverse scattering transform for the focusing nonlinear Schrödinger equation with nonzero boundary conditions”. In:J. Math. Phys.55.3 (2014)

  9. [9]

    Long-time asymptotics for the focusing nonlinear Schrödinger equation with nonzero boundary conditions at infinity and asymptotic stage of modulational instability

    G. Biondini and D. Mantzavinos. “Long-time asymptotics for the focusing nonlinear Schrödinger equation with nonzero boundary conditions at infinity and asymptotic stage of modulational instability”. In:Comm. Pure Appl. Math.70.12 (2017), pp. 2300–2365

  10. [10]

    Longtimeasymptoticbehaviorofthefocusing nonlinear Schrödinger equation

    M.Borghese,R.Jenkins,andK.T-RMcLaughlin.“Longtimeasymptoticbehaviorofthefocusing nonlinear Schrödinger equation”. In:Annales de l’Institut Henri Poincaré. Analyse Non Linéaire 35.4 (2018), pp. 887–920

  11. [11]

    Böttcher and Y

    A. Böttcher and Y. I. Karlovich.Carleson curves, Muckenhoupt weights, and Toeplitz operators. Vol. 154. Progress in Mathematics. Birkhäuser Verlag, Basel, 1997

  12. [12]

    Invariant measures for the 2D-defocusing nonlinear Schrödinger equation

    J. Bourgain. “Invariant measures for the 2D-defocusing nonlinear Schrödinger equation”. In: Comm. Math. Phys.176.2 (1996), pp. 421–445

  13. [13]

    Periodic nonlinear Schrödinger equation and invariant measures

    J. Bourgain. “Periodic nonlinear Schrödinger equation and invariant measures”. In:Comm. Math. Phys. 166 (1994), pp. 1–26

  14. [14]

    Long-time asymptotics of the nonlinear Schrödinger equation shock problem

    R. Buckingham and S. Venakides. “Long-time asymptotics of the nonlinear Schrödinger equation shock problem”. In:Comm. Pure Appl. Math.60.9 (2007), pp. 1349–1414

  15. [15]

    Emergent hydrodynamics in integrable quantum systems out of equilibrium

    O. A. Castro-Alvaredo, B. Doyon, and T. Yoshimura. “Emergent hydrodynamics in integrable quantum systems out of equilibrium”. In:Phys. Rev. X6.4 (2016), p. 041065

  16. [16]

    Generalized Hydrodynamic Limit for the Box-Ball System

    D. A. Croydon and M. Sasada. “Generalized Hydrodynamic Limit for the Box-Ball System”. In: Comm. Math. Phys.383 (2021), pp. 427–463

  17. [17]

    Riemann-Hilbert problems

    P. Deift. “Riemann-Hilbert problems”. In:Random matrices. Vol. 26. IAS/Park City Math. Ser. Amer. Math. Soc., Providence, RI, 2019, pp. 1–40

  18. [18]

    Universality for the Toda algorithm to compute the largest eigenvalue of a random matrix

    P. Deift and T. Trogdon. “Universality for the Toda algorithm to compute the largest eigenvalue of a random matrix”. In:Comm. Pure Appl. Math.71.3 (2018), pp. 505–536

  19. [19]

    A steepest descent method for oscillatory Riemann-Hilbert problems. Asymptotics for the MKdV equation

    P. Deift and X. Zhou. “A steepest descent method for oscillatory Riemann-Hilbert problems. Asymptotics for the MKdV equation”. In:Ann. of Math. (2)137.2 (1993), pp. 295–368

  20. [20]

    Long-time asymptotics for solutions of the NLS equation with initial data in a weighted Sobolev space

    P. Deift and X. Zhou. “Long-time asymptotics for solutions of the NLS equation with initial data in a weighted Sobolev space”. In:Comm. Pure and Appl. Math. Second of Two Special Issues Dedicated to the Memory of Jürgen K. Moser 56.8 (2003), pp. 1029–1077

  21. [21]

    Perturbation theory for infinite-dimensional integrable systems on the line. A case study

    P. Deift and X. Zhou. “Perturbation theory for infinite-dimensional integrable systems on the line. A case study”. In:Acta Math.188.2 (2002), pp. 163–262

  22. [22]

    Full derivation of the wave kinetic equation

    Y. Deng and Z. Hani. “Full derivation of the wave kinetic equation”. In:Invent. Math. 233.2 (2023), pp. 543–724. REFERENCES 25

  23. [23]

    Dispersive Asymptotics for Linear and Integrable Equations by the¯∂ Steepest Descent Method

    M. Dieng, Ken D. T-R McLaughlin, and P. D. Miller. “Dispersive Asymptotics for Linear and Integrable Equations by the¯∂ Steepest Descent Method”. In:Nonlinear Dispersive Partial Dif- ferential Equations and Inverse Scattering. Ed. by P. Miller, P. Perry, J.-C. Saut, and C. Sulem. Vol. 83. Fields Institute Communications. Springer, 2019, pp. 253–291

  24. [24]

    The thermodynamic limit of the Whitham equations

    G. A. El. “The thermodynamic limit of the Whitham equations”. In:Physics Letters. A311.4-5 (2003), pp. 374–383

  25. [25]

    Kinetic Equation for a Dense Soliton Gas

    G. A. El and A. M. Kamchatnov. “Kinetic Equation for a Dense Soliton Gas”. In:Phys. Rev. Lett. 95.20 (2005)

  26. [26]

    Kinetic equation for a soliton gas and its hydrodynamic reductions

    G. A. El, A. M. Kamchatnov, M. V. Pavlov, and S. A. Zykov. “Kinetic equation for a soliton gas and its hydrodynamic reductions”. In:J. Nonlinear Sci.21.2 (2011), pp. 151–191

  27. [27]

    Spectral theory of soliton and breather gases for the focusing nonlinear Schrödinger equation

    G. A. El and A. Tovbis. “Spectral theory of soliton and breather gases for the focusing nonlinear Schrödinger equation”. In:Phys. Rev. E101.5 (2020)

  28. [28]

    W. Feller. An Introduction to Probability Theory and Its Applications. 3rd. Vol. 1. Wiley Ser. Probab. Stat. Wiley, 1991

  29. [29]

    Method for Solving the Korteweg- deVries Equation

    C. S. Gardner, J. M. Greene, M. D. Kruskal, and R. M. Miura. “Method for Solving the Korteweg- deVries Equation”. In:Phys. Rev. Lett.19.19 (1967), pp. 1095–1097

  30. [30]

    Large deviations principle for the cubic NLS equation

    M. A. Garrido, R. Grande, K. M. Kurianski, and G. Staffilani. “Large deviations principle for the cubic NLS equation”. In:Comm. Pure Appl. Math.76.12 (2023), pp. 4087–4136

  31. [31]

    Rigorous asymptotics of a KdV soliton gas

    M. Girotti, T. Grava, R. Jenkins, and K. T-R McLaughlin. “Rigorous asymptotics of a KdV soliton gas”. In:Communications in Mathematical Physics384.2 (2021), pp. 733–784

  32. [32]

    Soliton versus the gas: Fredholm determinants, analysis, and the rapid oscillations behind the kinetic equation

    M. Girotti, T. Grava, R. Jenkins, K. T-R McLaughlin, and A. Minakov. “Soliton versus the gas: Fredholm determinants, analysis, and the rapid oscillations behind the kinetic equation”. In: Communications on Pure and Applied Mathematics76.11 (2023), pp. 3233–3299

  33. [33]

    Large N Asymptotics in Random Matrices

    A. Its. “Large N Asymptotics in Random Matrices”. In:Random Matrices, Random Processes and Integrable Systems. Ed. by J. Harnad. CRM Series in Mathematical Physics. Springer, 2011

  34. [34]

    Global existence for the derivative nonlinear Schrödinger equation with arbitrary spectral singularities

    R. Jenkins, J. Liu, P. Perry, and C. Sulem. “Global existence for the derivative nonlinear Schrödinger equation with arbitrary spectral singularities”. In:Anal. PDE13.5 (2020), pp. 1539– 1578

  35. [35]

    Global well-posedness for the derivative non-linear Schrödinger equation

    R. Jenkins, J. Liu, P. Perry, and C. Sulem. “Global well-posedness for the derivative non-linear Schrödinger equation”. In:Commun. Partial Differ. Equ.43.8 (2018), pp. 1151–1195

  36. [36]

    Soliton Resolution for the Derivative Nonlinear Schrödinger Equation

    R. Jenkins, J. Liu, P. Perry, and C. Sulem. “Soliton Resolution for the Derivative Nonlinear Schrödinger Equation”. In:Comm. Math. Phys.363 (2018), pp. 1003–1049

  37. [37]

    V. B. Matveev and M. A. Salle.Darboux Transformations and Solitons. Berlin: Springer, 1991

  38. [38]

    The focusing NLS equation with step-like oscillating background: asymptotics in a transition zone

    A. Boutet de Monvel, J. Lenells, and D. Shepelsky. “The focusing NLS equation with step-like oscillating background: asymptotics in a transition zone”. In:Comm. Math. Phys. 383 (2021), pp. 893–952

  39. [39]

    The focusing NLS equation with step-like oscillating background: scenarios of long-time asymptotics

    A. Boutet de Monvel, J. Lenells, and D. Shepelsky. “The focusing NLS equation with step-like oscillating background: scenarios of long-time asymptotics”. In:Comm. Math. Phys.383.2 (2021), pp. 893–952

  40. [40]

    The focusing NLS equation with step-like oscillating background: the genus 3 sector

    A. Boutet de Monvel, J. Lenells, and D. Shepelsky. “The focusing NLS equation with step-like oscillating background: the genus 3 sector”. In:Comm. Math. Phys.390.3 (2022), pp. 1081–1148

  41. [41]

    Nazarenko

    S. Nazarenko. Wave turbulence. Vol. 825. Lecture Notes in Physics. Springer, Heidelberg, 2011

  42. [42]

    Transport in out-of-equilibrium XXZ chains: Nonballistic behavior and correlation functions

    L. Piroli, J. De Nardis, M. Collura, B. Bertini, and M. Fagotti. “Transport in out-of-equilibrium XXZ chains: Nonballistic behavior and correlation functions”. In:Phys. Rev. B 96.11 (2017), p. 115124

  43. [43]

    Nonlinear dynamics of a soliton gas: Modified Korteweg– de Vries equation framework

    E.G. Shurgalina and E.N. Pelinovsky. “Nonlinear dynamics of a soliton gas: Modified Korteweg– de Vries equation framework”. In:Phys. Lett. A380.24 (2016), pp. 2049–2053

  44. [44]

    HydrodynamicequationsfortheAblowitz-LadikdiscretizationofthenonlinearSchrödinger equation

    H.Spohn.“HydrodynamicequationsfortheAblowitz-LadikdiscretizationofthenonlinearSchrödinger equation”. In:J. Math. Phys.63.3 (2022)

  45. [45]

    Hydrodynamic scales of integrable many-body systems.Hackensack,NJ:WorldScientific Publishing Co

    H.Spohn. Hydrodynamic scales of integrable many-body systems.Hackensack,NJ:WorldScientific Publishing Co. Pte. Ltd., 2024. 26 REFERENCES

  46. [46]

    Soliton Gas: Theory, Numerics and Experiments

    P. Suret, S. Randoux, A. Gelash, D. Agafontsev, B. Doyon, and G. A. El. “Soliton Gas: Theory, Numerics and Experiments”. In:Phys. Rev. E109.061001 (2024)

  47. [47]

    Maximal amplitudes of hyperelliptic solutions of the derivative nonlinear Schrödinger equation

    O. Wright. “Maximal amplitudes of hyperelliptic solutions of the derivative nonlinear Schrödinger equation”. In:Stud. Appl. Math.144.3 (2019), pp. 327–356

  48. [48]

    Sharp upper bound for amplitudes of hyperelliptic solutions of the focusing nonlinear Schrödinger equation

    O. C. Wright III. “Sharp upper bound for amplitudes of hyperelliptic solutions of the focusing nonlinear Schrödinger equation”. In:Nonlinearity 32 (2019), pp. 1929–1966

  49. [49]

    Kinetic Equation for Solitons

    V. Zakharov. “Kinetic Equation for Solitons”. In:Sov. Phys. - JETP33.3 (1971), pp. 538–541

  50. [50]

    Weak turbulence in media with decay spectrum

    V. Zakharov. “Weak turbulence in media with decay spectrum.” In:J. Appl. Mech. Tech. Phys. 4 (1965), pp. 22–24

  51. [51]

    V. E. Zakharov, V. S. L’vov, and G. Falkovich.Kolmogorov Spectra of Turbulence I: Wave Tur- bulence. Springer Series in Nonlinear Dynamics. Springer Berlin, Heidelberg, 1992

  52. [52]

    Exact theory of two-dimensional self-focusing and one- dimensional self-modulation of waves in nonlinear media

    V. E. Zakharov and A. B. Shabat. “Exact theory of two-dimensional self-focusing and one- dimensional self-modulation of waves in nonlinear media”. In:Zh. Eksp. Teor. Fiz61.1 (1971), pp. 118–134

  53. [53]

    The Riemann-Hilbert problem and inverse scattering

    X. Zhou. “The Riemann-Hilbert problem and inverse scattering”. In:SIAM J. Math. Anal.20.4 (1989), pp. 966–986. (Girotti) Department of Mathematics, Emory University, 400 Dowman Dr, Atlanta, GA 30322 Email address: manuela.girotti@emory.edu (Grava) SISSA, via Bonomea 265, 34136 Trieste, Italy, INFN sezione di Trieste, and School of Math- ematics, Universit...