Pith. sign in

REVIEW 2 major objections 4 minor 37 references

$L^{2}-L^{\infty}$ decay estimates and inviscid limits for Global smooth solutions to the compressible Navier-Stokes-Riesz system

T0 review · 2 major / 4 minor · reviewed 2026-07-11 · grok-4.5

Pith's one-line read Small viscous compressible Navier-Stokes-Riesz flows with O(ε) solenoidal velocity exist globally, decay, and converge to irrotational Euler-Riesz solutions at an explicit rate.

desk verdict Solid extension of NS-Riesz existence/decay to full s∈(0,1) plus the first quantitative global inviscid limit; the O(ε) solenoidal restriction is the only real structural limit. read the letter →

arxiv 2607.05562 v1 pith:KDUNBLJN submitted 2026-07-06 math.AP

classification math.AP MSC 35Q3035Q3176N1035B40
keywords compressibleNavier-Stokes-RieszglobalsmoothsolutionsL2-L∞decayinviscidlimitRieszpotentialnormal-formanalysisnegativeSobolevspaces
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 studies the three-dimensional compressible Navier-Stokes equations with a repulsive Riesz interaction that generalizes the Coulomb force of electrons. For small perturbations of a constant density-velocity equilibrium, and when the divergence-free part of the initial velocity is of size comparable to the viscosity parameter ε, it constructs a unique global smooth solution. That solution decays in both L^{2} and L∞, with rates that combine dispersion (uniform in viscosity) and dissipation (dependent on viscosity). As viscosity tends to zero the solution converges, for all time, to the corresponding irrotational solution of the inviscid Euler-Riesz system, with an explicit algebraic rate in Sobolev-type norms. The result therefore gives a rigorous justification of the inviscid limit for a nonlocal charged-fluid model and extends earlier global-existence theory from a restricted range of Riesz exponents to the full interval (0,1).

What carries the argument

A viscous irrotational approximation (density plus curl-free velocity) plus a correction system driven by the O(ε) solenoidal data, closed by viscosity-adapted dispersive estimates, normal-form analysis of resonant bilinear interactions, and energy estimates that control both positive and negative Sobolev norms.

What would settle it

Construct a family of initial data with solenoidal velocity of size independent of ε for which either the Navier-Stokes-Riesz solution blows up in finite time or the difference from the Euler-Riesz solution fails to tend to zero as ε o0.

Watch

Extended reading notes

Core claim

For every Riesz exponent s∈(0,1) and every viscosity ε∈(0,1], sufficiently small initial density and irrotational-velocity perturbations, together with a solenoidal velocity of size O(ε), produce a unique global smooth solution of the compressible Navier-Stokes-Riesz system that decays in L^{2} and L∞ and converges globally in time to the irrotational Euler-Riesz solution at the explicit rate O(ε^λs) in W^{k,p}.

Load-bearing premise

The divergence-free part of the initial velocity must be of size comparable to the viscosity; without that smallness the correction system cannot be controlled and global existence fails.

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

2 major / 4 minor

Summary. The paper studies the 3D repulsive compressible Navier-Stokes-Riesz system (Riesz exponent 0<s<1, viscosity 0<ε≤1). For small perturbations of a constant equilibrium with the solenoidal part of the initial velocity of size O(ε), it proves global existence and uniqueness of smooth solutions (Theorem 1.9). It derives L^{2} and L∞ time-decay rates that combine uniform-in-ε dispersive decay with ε-dependent dissipation, and establishes a global-in-time inviscid limit to the irrotational Euler-Riesz solution (same density and curl-free velocity) with an explicit rate O(ε^λs) in W^{k,p} (Theorem 1.11). The construction proceeds by a viscous irrotational approximation (1.8), a correction system (1.11) for the O(ε) solenoidal part, viscosity-adapted stationary-phase estimates for the phase b(ξ), normal-form analysis of the resonant Riesz phase Φ_jk via a modified kernel M, and nonlinear energy estimates controlling both positive and negative Sobolev norms.

Significance. The result fills a genuine gap: global strong solutions for the compressible Navier-Stokes-Riesz system were previously available only for s∈(1/2,1) (Wang-Zhang), while the full range 0<s<1 and the corresponding L∞ decay and inviscid-limit rate are new. The viscosity-adapted dispersive estimates (Proposition 2.1, Lemmas 2.2–2.5), the normal-form treatment of the Riesz phase (Proposition 2.12 and Appendix B), and the explicit global-in-time convergence rate are technically substantial and of clear interest to the mathematical fluid-dynamics community working on Euler/Navier-Stokes-Poisson/Riesz systems. The argument is self-contained once the external Euler-Riesz well-posedness (Lemma C.1) is granted, and the O(ε) solenoidal restriction is stated transparently.

major comments (2)
  1. The load-bearing structural hypothesis is that the solenoidal initial velocity Pu^ε_0 is O(ε) in H^{N1} (and O(ε) in Ḥ^{-ϑ} for the decay statements); see the statements of Theorems 1.7 and 1.9 and the a-priori bound (3.2). Without this smallness the coupling terms between the O(1) irrotational background and the correction (e.g., the integrals involving v·∇ abla^k c abla^k n) cannot be absorbed by the ε-scaled dissipation, and both global existence and the inviscid-limit rate fail. The restriction is correctly flagged by the authors (Remark 1.8) and is not hidden, but it should be emphasized more prominently in the introduction and abstract so that readers immediately understand the precise regime of validity.
  2. The L^{2} decay rates obtained for the full Navier-Stokes-Riesz solution (Theorem 1.9) are slower than the optimal rates of Wang-Zhang for s∈(1/2,1) (compare (1.7)). The authors note this in Remark 1.10 and attribute it to the approximation-correction construction. While the construction is natural for the inviscid-limit purpose, a short discussion of whether a direct spectral or pure-energy approach could recover the sharp rates for the full range 0<s<1 would strengthen the paper.
minor comments (4)
  1. The range of p (6<p<12 for s≤1/2, 8<p<16 for s>1/2) is dictated by the decay of the linear dispersive estimates and the artificial-viscosity error; a one-sentence explanation of why these particular upper bounds appear would help the reader.
  2. Notation for the two different energy functionals E_N (approximation) and E^{N1} (correction) is similar; a more distinctive notation (e.g., script E versus E) would reduce the risk of confusion when both appear in the same paragraph.
  3. A few typographical slips remain (e.g., “Navier-Stokes-Riesz” capitalization is inconsistent in the title and abstract; “the” missing before “Cauchy problem” in places). A careful proofreading pass is recommended.
  4. Lemma C.1 is cited as an external black-box; it would be useful to record explicitly that the initial-data regularity assumed there is compatible with the regularity required for the viscous approximation (N0≥6, N≥N0+14).

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: self-contained energy/dispersive estimates with external black-box input only for the Euler-Riesz target.

full rationale

The paper constructs global smooth solutions to the compressible Navier-Stokes-Riesz system by splitting into an irrotational viscous approximation (1.8) and a solenoidal correction (1.11), then obtains L2/L∞ decay via viscosity-adapted stationary-phase estimates on b(ξ) (Appendix A, Proposition 2.1), Shatah normal forms with a modified kernel M for the resonant Riesz phase Φjk (Proposition B.12, Lemma B.15), and iterative negative-Sobolev bootstrap (Propositions 2.13–2.14, 3.5). The inviscid-limit rate (Theorem 1.11) compares the constructed solution to the irrotational Euler-Riesz solution whose existence is imported as an external black-box (Lemma C.1 from Choi–Jung–Lee [12]). No parameter is fitted to data and then re-used as a prediction; no uniqueness theorem is imported from the present authors; no ansatz is smuggled via self-citation; and no quantity is defined in terms of the very object it is claimed to derive. The only structural restriction (solenoidal velocity O(ε)) is an explicit hypothesis, not a circular reduction. The derivation chain is therefore independent of its own conclusions.

Assumptions & free parameters 3 free parameters · 3 assumptions · 0 invented entities

The paper works entirely within classical PDE analysis. The only free parameters are technical cut-offs and smallness thresholds chosen for convenience; the axioms are standard functional-analytic facts plus the already-proved global existence for the irrotational Euler-Riesz system. No new physical entities are postulated.

free parameters (3)
  • κ0 (frequency cut-off separating dispersion and dissipation)
    Chosen small enough so that the phase function b(ξ) retains the desired derivative bounds on the support of χ_{ε,κ0}; value is not fitted to data but fixed once and for all.
  • δ0, δ1 (smallness thresholds for initial data and a-priori bounds)
    Absolute constants whose existence is asserted by the bootstrap; not numerically fitted.
  • p-range (6<p<12 for s≤1/2, 8<p<16 for s>1/2)
    Technical restriction forced by the decay exponents and the contribution of the artificial viscosity; chosen by hand to close the estimates.
assumptions (3)
  • domain assumption Global existence of small irrotational solutions to the compressible Euler-Riesz system (Lemma C.1, taken from Choi-Jung-Lee).
    Used as a black-box target for the inviscid limit; the present paper does not re-prove it.
  • standard math Standard multiplier theorems (Hörmander-Mikhlin), Kato-Ponce commutator estimates, Hardy-Littlewood-Sobolev, Van der Corput lemma.
    Invoked throughout Appendices A-B and the energy estimates.
  • domain assumption The artificial viscous approximation (1.8) preserves irrotationality when started from curl-free data.
    Proved by a short energy argument for the vorticity equation; essential for the construction.

how reviews work

0 comments
Cite this review

Pith. "Pith review of $L^{2}-L^{\infty}$ decay estimates and inviscid limits for Global smooth solutions to the compressible Navier-Stokes-Riesz system." pith.science (2026). https://pith.science/paper/KDUNBLJN

@misc{pith2026260705562,
  author       = {Pith},
  title        = {Pith review of: $L^2-L^\infty$ decay estimates and inviscid limits for Global smooth solutions to the compressible Navier-Stokes-Riesz system},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/KDUNBLJN}},
  note         = {Machine review of arXiv:2607.05562}
}
abstract

We study the Cauchy problem in $\mathbb{R}^{3}$ for the repulsive compressible Navier-Stokes-Riesz system with Riesz exponent $0<s<1$ and viscosity $0<\varepsilon\leq1$, where the Riesz interaction $\nabla(-\Delta)^{-s}(\rho-\bar{\rho})$ is a generalization of the Coulomb interaction for electrons. For small perturbations of a constant equilibrium, with the solenoidal component of the initial velocity of order $\mathcal{O}(\varepsilon)$, we prove the global existence and uniqueness of smooth solutions. We derive time-decay estimates in $L^{2}$ norms and $L^{\infty}$ norms that capture both uniform-in-$\varepsilon$ dispersive behavior and viscosity-dependent dissipation. We further establish a global-in-time inviscid limit to the irrotational global solution of the compressible Euler-Riesz system whose initial data consist of the same density and the curl-free component of the velocity, with an explicit convergence rate in $W^{k,p}$ norms. The proof combines viscosity-adapted dispersive estimates, normal-form analysis and nonlinear energy estimates with control of both negative and positive Sobolev norms.

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

37 extracted references · 1 canonical work pages

  1. [1]

    343,Springer Science & Business Media, 2011

    Bahouri, Hajer and Chemin, Jean-Yves and Danchin, Raphaël , Fourier analysis and nonlinear partial differential equations, Vol. 343,Springer Science & Business Media, 2011

  2. [2]

    Bella, Peter, Long time behavior of weak solutions to Navier-Stokes-Poisson system,J. Math. Fluid Mech.14 (2012), no. 2, 279–294

  3. [3]

    Hyperbolic Differ

    Blanc, Xa vier and Danchin, Raphaël and Ducomet, Bernard and Nečasov á, Šárka , The global existence issue for the compressible Euler system with Poisson or Helmholtz couplings,J. Hyperbolic Differ. Equ. 18 (2021), no. 1, 169–193

  4. [4]

    and Dauxois, T

    Campa, A. and Dauxois, T. and F anelli, D. and Ruffo, S. , Physics of Long-Range Interacting Systems, Oxford University Press: Oxford(2014)

  5. [5]

    and Choi, Young-Pil and Perez, Sergio P

    Carrillo, José A. and Choi, Young-Pil and Perez, Sergio P. , A review on attractive–repulsive hydro- dynamics for consensus in collective behavior, In: Active Particles, Vol. 1: Advances in Theory, Models, and Applications, Birkhäuser/Springer, Cham, (2017), 259–298

  6. [6]

    and Choi, Young-Pil , Mean-Field Limits: From particle descriptions to macroscopic equations, Arch

    Carrillo, José A. and Choi, Young-Pil , Mean-Field Limits: From particle descriptions to macroscopic equations, Arch. Rational Mech. Anal.241(3) (2021), 1529–1573

  7. [7]

    Global Existence and Nonlinear Stability of Finite-Energy Solutions of the Compressible Euler-Riesz Equations with Large Initial Data of Spherical Symmetry

    Carrillo, José A. and Charles, Samuel R. and Chen, Gui-Qiang and Yuan, Dif an , Global existence and nonlinear stability of finite-energy solutions of the compressible Euler-Riesz equations with large initial data of spherical symmetry. (2025) arXiv:2502.13094v1

  8. [8]

    and He, Lin and W ang, Yong and Yuan, Dif an , Global solutions of the compressible Euler-Poisson equations with large initial data of spherical symmetry,Comm

    Chen, Gui-Qiang G. and He, Lin and W ang, Yong and Yuan, Dif an , Global solutions of the compressible Euler-Poisson equations with large initial data of spherical symmetry,Comm. Pure Appl. Math.77 (2024), no. 6, 2947–3025

Show all 37 references
  1. [9]

    Chen, Gui-Qiang G. and Huang, Feimin and Li, Tianhong and W ang, Weiqiang and W ang, Yong , Global finite-energy solutions of the compressible Euler-Poisson equations for general pressure laws with large initial data of spherical symmetry,Comm. Math. Phys.405 (2024), no. 3, Pa...

  2. [10]

    Differential Equations306 (2022), 296–332

    Choi, Young-Pil and Jeong, In-Jee , On well-posedness and singularity formation for the Euler-Riesz system, J. Differential Equations306 (2022), 296–332

  3. [11]

    253 (2025), Paper No

    Choi, Young-Pil and Jung, Jinwook and Lee, Yoonjung , The global Cauchy problem for the Euler-Riesz equations, Nonlinear Anal. 253 (2025), Paper No. 113724, 35

  4. [12]

    Choi, Young-Pil and Jung, Jinwook and Lee, Yoonjung , Global smooth solutions to the irrotational Euler-Riesz system in three dimensions,Trans. Amer. Math. Soc.379 (2026), no. 1, 241–288

  5. [13]

    Ducomet, Bernard and Feireisl, Eduard and Petzeltov á, Hana and Straškraba, Iv an , Global in time weak solutions for compressible barotropic self-gravitating fluids,Discrete Contin. Dyn. Syst.11 (2004), no. 1, 113–130

  6. [14]

    and Ducomet, B

    Danchin, R. and Ducomet, B. , On the global existence for the compressible Euler-Riesz system,J. Math. Fluid Mech. 24 (2022), no. 2, Paper No. 48, 25

  7. [15]

    Guo, Yan, Smooth irrotational flows in the large to the Euler-Poisson system inR3+1, Comm. Math. Phys. 195 (1998), no. 2, 249–265

  8. [16]

    Henri Poincaré8 (2007), no.7, 1303–1331

    Gustafson, Stephen and Nakanishi, Kenji and Tsai, Tai-Peng , Global dispersive solutions for the Gross-Pitaevskii equation in two and three dimensions,Ann. Henri Poincaré8 (2007), no.7, 1303–1331

  9. [17]

    249, Springer, New York, 2008

    Graf akos, Loukas, Classical Fourier analysis, second edition, Graduate Texts in Mathematics, Vol. 249, Springer, New York, 2008. 62

  10. [18]

    Germain, Pierre and Masmoudi, Nader and Shatah, Jalal , Global solutions for 3D quadratic Schrödinger equations, Int. Math. Res. Not. IMRN3 (2009), no. 3, 414–432

  11. [19]

    Germain, Pierre and Masmoudi, Nader and Shatah, Jalal , Global solutions for the gravity water waves equation in dimension 3,Ann. of Math. 175 (2012), no. 2, 691–754

  12. [20]

    Guo, Yan and Pausader, Benoit , Global smooth ion dynamics in the Euler-Poisson system,Comm. Math. Phys. 303 (2011), no. 1, 89–125

  13. [21]

    Germain, Pierre and Masmoudi, Nader and Pausader, Benoit , Nonneutral global solutions for the electron Euler-Poisson system in three dimensions,SIAM J. Math. Anal.45 (2013), no. 1, 267–278

  14. [22]

    and Pausader, Benoit , The Euler-Poisson system in 2D: global stability of the constant equilibrium solution,Int

    Ionescu, Alexandru D. and Pausader, Benoit , The Euler-Poisson system in 2D: global stability of the constant equilibrium solution,Int. Math. Res. Not. IMRN(2013), no. 4, 761–826

  15. [23]

    Pure Appl

    Kato, Tosio and Ponce, Gusta vo, Commutator estimates and the Euler and Navier-Stokes equations,Comm. Pure Appl. Math.41 (1988), no. 7, 891–907

  16. [24]

    Li, Hai-Liang and Matsumura, Akitaka and Zhang, Guojing , Optimal decay rate of the compressible Navier-Stokes-Poisson system inR3, Arch. Ration. Mech. Anal.196 (2010), no. 2, 681–713

  17. [25]

    Li, Dong, On Kato-Ponce and fractional Leibniz,Rev. Mat. Iberoam.35 (2019), no. 1, 23–100

  18. [26]

    Li, Dong and Wu, Yifei , The Cauchy problem for the two dimensional Euler-Poisson system,J. Eur. Math. Soc. (JEMS) 16 (2014), no. 10, 2211–2266

  19. [27]

    Lewin, Mathieu, Coulomb and Riesz gases: the known and the unknown,J. Math. Phys.63(6) (2022), 061101

  20. [28]

    Perthame, Benoît, Nonexistence of global solutions to Euler-Poisson equations for repulsive forces,Japan J. Appl. Math. 7 (1990), no. 2, 363–367

  21. [29]

    Rousset, Frédéric and Sun, Changzhen , Stability of equilibria uniformly in the inviscid limit for the Navier-Stokes-Poisson system,Ann. Inst. H. Poincaré C Anal. Non Linéaire38 (2021), no. 4, 1255–1294

  22. [30]

    Pure Appl

    Shatah, Jalal, Normal forms and quadratic nonlinear Klein-Gordon equations,Comm. Pure Appl. Math.38 (1985), no. 5, 685–696

  23. [31]

    Sideris, Thomas C , Formation of singularities in three-dimensional compressible fluids,Comm. Math. Phys. 101 (1985), no. 4, 475–485

  24. [32]

    (PMS-43), vol

    Stein, Elias M , Harmonic analysis: real-variable methods, orthogonality, and oscillatory integrals. (PMS-43), vol. 43,Princeton University Press, 1993

  25. [33]

    8, 1985–2004

    W ang, Dehua and W ang, Zejun, Large BV solutions to the compressible isothermal Euler-Poisson equations with spherical symmetry,Nonlinearity 19 (2006), no. 8, 1985–2004

  26. [34]

    Differential Equations248 (2010), no

    W ang, Weike and Wu, Zhigang , Pointwise estimates of solution for the Navier-Stokes-Poisson equations in multi-dimensions, J. Differential Equations248 (2010), no. 7, 1617–1636

  27. [35]

    Differential Equations 253 (2012), no

    W ang, Yanjin, Decay of the Navier-Stokes-Poisson equations,J. Differential Equations 253 (2012), no. 1, 273–297

  28. [36]

    Differential Equations259 (2015), no

    W ang, Yu-Zhu and W ang, Keyan, Asymptotic behavior of classical solutions to the compressible Navier- Stokes-Poisson equations in three and higher dimensions,J. Differential Equations259 (2015), no. 1, 25–47

  29. [37]

    Differential Equations438 (2025) Paper No

    W ang, Shu and Zhang, Shuzhen, The initial value problem of the fractional compressible Navier-Stokes-Poisson system, J. Differential Equations438 (2025) Paper No. 113359, 80. University of W arsa w, Institute of Applied Mathematics and Mechanics, Banacha 2, 02-097 W arsza w a...

Pith tools

Reviewed July 11, 2026 · model on record in the stance chip above.