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REVIEW 2 major objections 3 minor 36 references

Smooth nonradial stationary solutions to SQG via the half-Yamabe equation

T0 review · 2 major / 3 minor · reviewed 2026-08-05 · deepseek-v4-flash

Pith's one-line read This paper constructs infinitely many smooth nonradial stationary solutions to the surface quasi-geostrophic equation, answering a long-standing existence question.

desk verdict A credible attack on a real open problem, but the submitted text has a load-bearing gap at the final step that the authors have flagged themselves. read the letter →

arxiv 2608.00563 v1 pith:36IUPBTV submitted 2026-08-01 math.AP

classification math.AP MSC 35Q3135R1135B3335B38
keywords surfacequasi-geostrophicequationstationarysolutionshalf-Yamabesign-changingLyapunov-SchmidtreductionregularpolygonconcentrationfractionalLaplacian
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 claims that the surface quasi-geostrophic (SQG) equation has infinitely many smooth, nonradial, finite-energy steady states, a class for which only trivial radial examples were previously available. The engine is the half-Yamabe equation (−Δ)^{1/2}ψ = ψ³: any solution yields a stationary SQG temperature θ = ψ³. The authors construct nonradial sign-changing half-Yamabe solutions by placing k scaled copies of the standard bubble at the vertices of a regular k-gon, subtracting one central bubble, and correcting the error with a Lyapunov–Schmidt reduction. At the concentration scale δ_k ∼ (k log k)^{−2}, an exact solution emerges, and as k→∞ the corresponding SQG flows converge, after a log k rescaling, to a radial profile plus a circular vortex-sheet correction. The existence proof relies on one differentiability step that is deferred in the manuscript rather than fully written out.

What carries the argument

The approximate solution U_{k,t}=Σ_j U_{j,k,t}−U, with k bubbles at the vertices of a regular k-gon and one central bubble subtracted, is engineered to lie in the symmetry space H_k: functions even in x₂, k-fold symmetric, and invariant under the Kelvin transform x↦x/|x|². The argument is a Lyapunov–Schmidt reduction: linearize about U_{k,t}, prove a uniform a priori estimate for the projected linearized operator on the orthogonal complement of the approximate kernel direction Z_{k,t}, solve the projected nonlinear equation, and finally choose the scale parameter t by energy maximization. The concentration scale δ_k=(k log k)^{−2} and the parameter t are tuned so the leading energy is k + ∥U

What would settle it

Directly compute ∂_t Z_{k,t} and ∂_t φ_{k,t} at t=t_k and check whether both are even, k-fold symmetric, and Kelvin-invariant; if either fails, the chain-rule identity (3.69) does not follow and c_k need not vanish. Alternatively, solve the projected problem (3.54) numerically for finite k near t=π²/2 and measure the projected residual I′(U_{k,t}+φ_{k,t})−c_k⟨Z_{k,t},·⟩ after choosing t_k as the energy maximizer; a nonzero c_k at machine precision would falsify the claim.

Watch

Extended reading notes

Core claim

The paper's central discovery is a family ψ_k of exact solutions to the half-Yamabe equation (−Δ)^{1/2}ψ = ψ³, built as a regular k-gon cluster of k scaled copies of the standard bubble U(x)=(1+|x|²)^{−1/2} minus one central copy, plus a small remainder φ_k. Each ψ_k is sign-changing, smooth, nonradial, and has finite Ḣ^{1/2} energy; the concentration scale bδ_k ∼ (k log k)^{−2} is chosen so the cluster is neither too tightly nor too loosely packed. This is the first finite-energy sign-changing solution at the critical endpoint s=1/2, and it disproves the rate k^{−2} conjectured in the fractional-Yamabe literature. The proof is a Lyapunov–Schmidt reduction in Ḣ^{1/2}: solving the projected

Load-bearing premise

In Section 3.4, after equation (3.68), the proof that ∂_t U_{k,t} and ∂_t φ_{k,t} belong to the symmetry space H_k is deferred to another version; without that differentiability, the Lagrange multiplier c_k need not vanish and the constructed ψ_k need not solve the unprojected half-Yamabe equation.

Editorial extensions

If this is right

  • The open question of whether SQG admits smooth nonradial finite-energy steady states is answered affirmatively: there are infinitely many, indexed by k.
  • The half-Yamabe equation at the critical endpoint s=1/2 in two dimensions has sign-changing finite-energy solutions; their concentration rate (k log k)^{−2} refutes the rate k^{−2} conjectured for all s∈(0,1).
  • For large k, after multiplying by log k, the SQG solutions converge distributionally to the radial profile −U³ plus a vortex sheet on the unit circle, giving a smooth approximation of a circular vortex sheet.
  • The improved Sobolev inequality for k-fold symmetric functions is a standalone tool for controlling interactions among many symmetrically placed concentration points.
  • The reduction to a one-dimensional energy maximization shows that the asymptotic polygon radius is selected by a universal balance, with the maximizer t=π²/2 fixing the scale parameter.

Reading between the lines

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

  • If the deferred differentiability step is supplied, the construction is a template: any nonlinearity for which the bubble is nondegenerate and the k-gon interaction has the right repulsion–attraction balance should produce analogous stationary active-scalar states.
  • The logarithmic correction at s=1/2 is a natural target for numerical continuation: solving the half-Yamabe equation with the k-gon ansatz for moderate k should show δ_k scaling as (k log k)^{−2}, and the exponent of the log factor can be measured directly.
  • The vortex-sheet limit suggests these smooth steady states sit at the threshold where the kinetic energy diverges like log k; understanding this rate could connect to selection of weak SQG solutions, though the paper does not discuss stability.
  • The capacity-based Sobolev inequality for k-fold functions is likely reusable in other concentration problems where many symmetric small sets must be kept weakly interacting.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

2 major / 3 minor

Summary. The paper claims two main results. Theorem 1.2 constructs, for all sufficiently large k, a finite-energy sign-changing solution ψ_k of the half-Yamabe equation (−Δ)^{1/2}ψ = ψ^3 in R^2 of the form ψ_k = ∑_{j=1}^k (1/(bδ_k)^{1/2})U((x−ξ_j^k)/(bδ_k)) − U(x) + φ_k, where the centers ξ_j^k are the vertices of a regular k-gon, bδ_k ∼ 1/(k log k)^2, and φ_k → 0 in ˙H^{1/2}. The proof is a Lyapunov–Schmidt reduction in the symmetry space H_k, with an improved Sobolev-type inequality (Prop. 2.2) and a uniform linear estimate (Lemma 3.3) as key ingredients. Theorem 1.1 then asserts that θ_k = ψ_k^3 are infinitely many smooth nonradial finite-energy stationary solutions of the SQG equation, with the stated weak convergence (1.2) to a radial profile plus a vortex-sheet measure at order (log k)^{-1}.

Significance. If the construction is completed, the paper resolves a well-known open problem: existence of smooth nonradial finite-energy stationary solutions to SQG. It also provides the first finite-energy sign-changing solutions to the two-dimensional half-Yamabe equation at the endpoint s = 1/2, with a concentration rate bδ_k ∼ (k log k)^{-2} that disproves the rate k^{-2} conjectured in [18] for this endpoint. The paper is largely self-contained: it proves the required uniform linear theory, supplies a new improved Sobolev inequality for k-fold symmetric functions, and uses only external classification and nondegeneracy results. The main weakness is a self-admitted missing differentiability argument in the final step of Theorem 1.2; there is also a factor-two error in the limiting constant of Theorem 1.1.

major comments (2)
  1. [§3.4, Eq. (3.68)-(3.71)] The proof that the Lagrange multiplier c_k vanishes requires that ∂_t U_{k,t} and ∂_t φ_{k,t} belong to H_k, because the representation I'(ψ_k)=c_k⟨Z_{k,t},·⟩ is only available on H_k. The manuscript itself defers this proof in the Spanish note immediately after (3.68), saying that the proof that ∂_t U_{k,t} and ∂_t φ_{k,t} are in H_k is postponed to another version. This is not a cosmetic omission: without membership in H_k, the chain rule in (3.69) cannot be applied, and the conclusion c_k=0 in (3.69)–(3.71) is unsupported. Since c_k=0 is exactly what converts the projected solution into a genuine solution of the unprojected half-Yamabe equation, this gap is load-bearing for both Theorem 1.2 and Theorem 1.1. I request that the authors supply the missing proof (or a precise reference) in the revision.
  2. [Theorem 1.1, Eq. (1.2); §4.2, Eq. (4.7)] The stated limiting constant is off by a factor of two. From the computation in (4.6), the prefactor is √(t_k δ_k) = √t_k/(k log k). Summing over j, multiplying by log k, and using the convergence of the empirical measure to (1/2π)σ_{∂D}, the limit is √t_k σ_{∂D} in the sense of measures. Since t_k→π^2/2, the correct constant is π/√2, not π√2. Thus Eq. (4.7) and the statement of Theorem 1.1 in (1.2) are false as written, although the existence claim itself is unaffected. This should be corrected.
minor comments (3)
  1. [Theorem 1.2] The symbol bδ_k appears in Theorem 1.2 and the introduction, while the proof consistently uses δ_k defined in (2.3). Please unify the notation.
  2. [Remark 3.7] The function f is written as π√2 t − t, which is linear and has no maximum. The computation in Lemma 3.8 shows the intended function is f(t)=π√(2t)−t, whose maximum at t=π^2/2 is nondegenerate. Please fix the typesetting.
  3. [Proposition 4.1] A concern was raised that the rotation by π/k in the nonradiality proof might permute the k bubbles when k is even, invalidating the lower bound. On reading the argument, this concern does not land: for even k, R_{π/k} maps the vertex set to the interlaced half-step angles, not to itself, so the lower bound in (4.3) is not voided. No revision seems needed on this point.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity found: the Lyapunov–Schmidt reduction is self-contained; the deferred differentiability proof after (3.68) is a correctness gap, not a circular step.

full rationale

The derivation of Theorem 1.2 is a standard Lyapunov–Schmidt reduction with an explicit ansatz U_{k,t} in (3.1). The error estimate (Lemma 3.1), the projected linear estimate (Lemma 3.3), the nonlinear fixed-point argument (Proposition 3.5), and the energy expansion (Proposition 3.6) are all internal estimates. The free parameter t is fixed by maximizing the paper's own reduced energy f(t)=π√2 t − t coming from (3.56); it is not fitted to data and no quantity called a prediction is an input in disguise. External citations are used for standard ingredients (positive-solution classification [8,24,25], nondegeneracy of the limit bubble [15,7], capacitary inequalities [27], interaction estimates [30]) and none of these is authored by the present paper's authors nor assumes the existence of nonradial multi-bump half-Yamabe solutions. The SQG application in Section 4 is the classical observation that θ=ψ³ yields stationary solutions when (−Δ)^{1/2}ψ=ψ³, together with regularity and nonradiality arguments; it does not assume the target conclusion. The only flagged issue is the Spanish note after (3.68): "Si no definimos el I de H_k en Resto no es cierto. Considerar adelantar la prueba de que ∂_tU_{k,t} y ∂_tϕ_{k,t} estan en H_k en otra versión." This is an omitted proof needed to justify (3.69)–(3.71) and conclude c_k=0; if the differentiability claim fails, Theorem 1.2 is unsupported. But this is a gap in the derivation chain, not circularity: it is not an input defined in terms of the output, nor a fitted parameter renamed as a prediction, nor a load-bearing self-citation. The central construction does not reduce by construction to its own inputs, so the circularity score is 0.

Assumptions & free parameters 2 free parameters · 6 assumptions · 0 invented entities

The central claim rests on no invented entities. Two internally chosen numbers act as free parameters: the bubble scale δ_k = (k log k)^{−2} (the rate quoted in Theorem 1.2 is this choice, not a fitted prediction) and the ansatz parameter t, fixed by maximizing the reduced energy f(t) = π√(2t) − t at t_max = π²/2. The axioms are standard external inputs (bubble classification [8,24,25]; nondegeneracy [15,7]; capacitary inequality [27]; interaction estimates [30]) plus the classical F(ψ)-bridge to SQG and an implicit, unexamined compatibility assumption that the new solutions escape the rigidity hypotheses of [19]. The latter is the only axiom with a real risk of being false.

free parameters (2)
  • δ_k (bubble concentration scale) = 1/(k log k)^2
    Chosen scale for the k bubbles in (2.3); Theorem 1.2's rate bδ_k ∼ (k log k)^{−2} is this choice. It is selected to balance error terms in Lemmas 3.1 and 3.3, not fitted to external data.
  • t (ansatz parameter controlling polygon radius and bubble width) = t_k → π^2/2
    Free parameter in the ansatz (2.2)-(2.3); fixed by maximizing the reduced energy f(t) = π√(2t) − t in Proposition 3.6 and Remark 3.7. The final scale of the SQG vortex-sheet limit in (1.2) inherits this value.
assumptions (6)
  • standard math All positive solutions of (−Δ)^{1/2}u = u³ in R² are the bubbles U_{δ,ξ}(x) = δ^{1/2}/(δ²+|x−ξ|²)^{1/2}
    Invoked after (1.4) and in Section 2 to justify seeking sign-changing solutions; cited to [8,24,25].
  • standard math Nondegeneracy of the linearized half-Yamabe operator: kernel span{Z^{(0)}, Z^{(1)}, Z^{(2)}} as in (3.18)
    Used in Lemma 3.3, Step 4.2 and Step 5, to identify limits of rescaled kernels; cited to [15, Theorem 1.1] and [7, Lemma A.1].
  • standard math Capacitary strong-type inequality ∫₀^∞ s·cap({|v|≥s})ds ≤ 2∫_{R³}|∇v|²dx
    Key input to the improved Sobolev inequality in Proposition 2.2; cited to [27, Sect. 2.3.1].
  • standard math Bubble interaction estimates Σ_{j=2}^k 1/|x−ξ_{j,k,t}| ≲ k log k in Ω₁, and the related log-type bound (2.8)
    Used throughout Lemma 2.1 and Section 3; imported from [30, (A.6)-(A.7)].
  • domain assumption The constructed smooth stationary SQG solutions do not fall under the rigidity hypotheses of [19]
    The introduction cites [19] for symmetry rigidity of SQG steady states while claiming the nonradial finite-energy problem is open; the text never states which hypothesis of [19] is violated. If a rigidity theorem in [19] covered this class, Theorem 1.1 would be false.
  • domain assumption Classical observation: if ψ solves (−Δ)^{1/2}ψ = F(ψ), then θ = F(ψ) is a stationary SQG solution
    Section 1, displayed line before (1.3); the bridge between Theorems 1.2 and 1.1.

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Pith. "Pith review of Smooth nonradial stationary solutions to SQG via the half-Yamabe equation." pith.science (2026). https://pith.science/paper/36IUPBTV

@misc{pith2026260800563,
  author       = {Pith},
  title        = {Pith review of: Smooth nonradial stationary solutions to SQG via the half-Yamabe equation},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/36IUPBTV}},
  note         = {Machine review of arXiv:2608.00563}
}
read the original abstract

We prove the existence of infinitely many smooth nonradial stationary solutions to the surface quasi-geostrophic (SQG) equation with finite kinetic energy. Our construction is based on a family of nonradial sign-changing solutions to the two-dimensional half-Yamabe equation, obtained via a Lyapunov--Schmidt reduction and concentrated at the vertices of a regular polygon. As the number of vertices tends to infinity, the associated stationary SQG solutions converge to a radial stationary profile centered at the origin, together with a lower-order vortex sheet correction.

Figures

Figures reproduced from arXiv: 2608.00563 by the authors.

Figure 1
Figure 1. Schematic picture of the decomposition of Ω1. Then, the integral can be divided as Z Ω1 U 4−α−β U α 1,k,tX k j=2 Uj,k,tβ dx = Z Ω1,1 U 4−α−β U α 1,k,tX k j=2 Uj,k,tβ dx + Z Ω1,2 U 4−α−β U α 1,k,tX k j=2 Uj,k,tβ dx + Z Ω1,3 U 4−α−β U α 1,k,tX k j=2 Uj,k,tβ dx =: I1 + I2 + I3. We start dealing with I1. Note that I1 = t α+β 2 δ α+β 2 k Z Ω1,1 1 (1 + |x| 2) 4−α−β 2 1 (t 2δ 2 k + |x − ξ1,k,t| 2) α 2 X k j=2 1 (t… view at source ↗
Figure 2
Figure 2. Schematic picture of Uk,t and its level curves when k = 5 [PITH_FULL_IMAGE:figures/full_fig_p010_2.png] view at source ↗
Figure 3
Figure 3. Schematic picture of Uk,t and its level curves when k = 12. As a first step towards the proof of Theorem 1.2, we will measure how well this approximate solution “solves” (1.4), but first we are going to reformulate (1.4) using the inverse of the half-Laplacian. By Sobolev inequality, the embedding H˙ 1 2 ,→ L 4 is continuous. Hence, using the Riesz representation theorem, we can define the continuous operator (−∆)− … view at source ↗

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Works this paper leans on

36 extracted references · 33 canonical work pages

  1. [18]

    Garrido, M

    D. Garrido, M. Musso, Entire sign-changing solutions with finite energy to the fractional Yamabe equation, Pacific J. Math. 283 (1) (2016) 85–114

  2. [1]

    K. Abe, J. G´ omez-Serrano, I.-J. Jeong, Homogeneous steady states for the generalized surface quasi-geostrophic equations. arXiv:2510.03009

  3. [2]

    W. Ao, J. D´ avila, M. del Pino, M. Musso, J. Wei, Travelling and rotating solutions to the generalized inviscid surface quasi-geostrophic equation, Trans. Amer. Math. Soc. 374(9) (2021) 6665–6689

  4. [3]

    Buckmaster, S

    T. Buckmaster, S. Shkoller, V. Vicol, Nonuniqueness of weak solutions to the SQG equation, Comm. Pure Appl. Math., 72(9) (2019) 1809–1874

  5. [4]

    Castro, D

    A. Castro, D. C´ ordoba, J. G´ omez-Serrano, Global smooth solutions for the inviscid SQG equation, Mem. Amer. Math. Soc. 266 (2020) 89pp

  6. [5]

    Castro, D

    A. Castro, D. Faraco, F. Mengual, M. Solera, Unstable vortices, sharp non-uniqueness with forcing, and global smooth solutions for the SQG equation. arXiv:2502.10274

  7. [6]

    S.-Y. A. Chang, M. M. Gonz´ alez, Fractional Laplacian in conformal geometry, Adv. Math. 226 (2) (2011) 1410–1432

  8. [7]

    H. Chen, S. Kim, J. Wei, Sharp quantitative stability estimates for critical points of fractional Sobolev inequalities, Int. Math. Res. Not. 12 (2025) 36pp

Show all 36 references
  1. [8]

    W. Chen, C. Li, B. Ou, Classification of solutions for an integral equation. Comm. Pure Appl. Math. 59 (3) (2006) 330–343

  2. [9]

    Cheng, H

    X. Cheng, H. Kwon, D. Li, Non-uniqueness of steady-state weak solutions to the surface quasigeostrophic equations, Comm. Math. Phys. 388 (3) (2021) 1281–1295

  3. [10]

    Constantin, A

    P. Constantin, A. J. Majda, E. Tabak, Formation of strong fronts in the 2-D quasigeostrophic thermal active scalar Nonlin- earity 7(6) (1994), 1495–1533

  4. [11]

    C´ ordoba, J

    D. C´ ordoba, J. Lucas-Manch´ on, L. Mart ´ ınez-Zoroa, Strong ill-posedness and non-existence in Sobolev spaces for generalized- SQG, Nonlinearity 38 (8) (2025)

  5. [12]

    C´ ordoba, L

    D. C´ ordoba, L. Mart ´ ınez-Zoroa, Non existence and strong ill-posedness inCk and Sobolev spaces for SQG, Adv. Math. 407 (2022) 74pp

  6. [13]

    C´ ordoba, L

    D. C´ ordoba, L. Mart ´ ınez-Zoroa, W. S. O˙ za´ nski, Instantaneous continuous loss of regularity for the SQG equation, Adv. Math. 481 (2025) 49pp

  7. [14]

    M. Dai, Q. Peng, Non-unique stationary solutions of forced SQG, arXiv:2302.03283

  8. [15]

    D´ avila, M

    J. D´ avila, M. del Pino, Y. Sire, Nondegeneracy of the bubble in the critical case for nonlocal equations, Proc. Amer. Math. Soc. 141 (2013) 3865–3870

  9. [16]

    del Pino, M

    M. del Pino, M. Musso, F. Pacard, A. Pistoia, Large energy entire solutions for the Yamabe equation, J. Differential Equations 251(9) (2011) 2568–2597

  10. [17]

    Dipierro, M

    S. Dipierro, M. Medina, E. Valdinoci,Fractional elliptic problems with critical growth in the whole ofR n,volume 15 of Appunti. Scuola Normale Superiore di Pisa. Edizioni della Normale, Pisa (2017)

  11. [19]

    G´ omez-Serrano, J

    J. G´ omez-Serrano, J. Park, J. Shi, Y. Yao, Symmetry in stationary and uniformly-rotating solutions of active scalar equations, Duke Math. J. 170 (13) (2021) 2957–3038

  12. [20]

    M. M. Gonz´ alez, J. Qing, Fractional conformal Laplacians and fractional Yamabe problems, Anal. PDE 6 (2013) 1535–1576

  13. [21]

    Gravejat, D

    P. Gravejat, D. Smets, Smooth travelling-wave solutions to the inviscid surface quasi-geostrophic equation, Int. Math. Res. Not. 6 (2019) 1744–1757

  14. [22]

    Hance-Olsen, H

    H. Hance-Olsen, H. Holden, The Kolmogorov–Riesz compactness theorem, Expo. Math. 28 (2010) 385–394

  15. [23]

    Jeong, J

    I.-J. Jeong, J. Kim, Strong ill-posedness for SQG in critical Sobolev spaces, Anal. PDE 17 (1) (2024) 133–170

  16. [24]

    Li, Remark on some conformally invariant integral equations: the method of moving spheres

    Y.Y. Li, Remark on some conformally invariant integral equations: the method of moving spheres. J. Eur. Math. Soc. 6 (2) (2004) 153–180

  17. [25]

    Y.Y. Li, M. Zhu, Uniqueness theorems through the method of moving spheres. Duke Math. J. 80 (2) (1995) 383–417

  18. [26]

    Marchand

    F. Marchand. Existence and regularity of weak solutions to the quasi-geostrophic equations in the spacesL p or ˙H − 1 2 Comm. Math. Phys., 277(1) (2008), 45–67

  19. [27]

    V.G. Maz’ya,Sobolev spaces with applications to elliptic partial differential equations, second, revised and augmented edition, Grundlehren der mathematischen Wissenschaften, 342, Springer, Heidelberg, 2011

  20. [28]

    Medina, M

    M. Medina, M. Musso, Doubling nodal solutions to the Yamabe equation inR n with maximal rank, J. Math. Pures. Appl. 152(9) (2021) 145–188

  21. [29]

    M. M. G. Pacual-Caballo, Stationary homogeneous solutions for the inviscid SQG equation. arXiv:2510.03108. SMOOTH NONRADIAL STATIONARY SOLUTIONS TO THE SQG EQUATION 43

  22. [30]

    Premoselli, J

    B. Premoselli, J. V´ etois, Compactness of sign-changing solutions to scalar curvature-type equations with bounded negative part, J. Differential Equations 266 (2019) 7416–7458

  23. [31]

    S. G. Resnick, Dynamical problems in non-linear advective partial differential equations. 1995. PhD thesis, University of Chicago, Department of Mathematics

  24. [32]

    Robert, J

    F. Robert, J. V´ etois, A general theorem for the construction of blowing-up solutions to some elliptic nonlinear equations via Lyapunov-Schmidt’s reduction,Concentration compactness and profile decomposition, Bangalore(2011), Trends Math., Springer, Basel (2013) 85–116

  25. [33]

    X. Su, E. Valdinoci, Y. Wei, J. Zhang, Regularity results for solutions of mixed local and nonlocal elliptic equations, Math. Z. 302(3) (2022) 1855–1878

  26. [34]

    Taylor,Partial Differential Equations II: Qualitative studies of linear equations.Applied Mathematical Sciences

    M. Taylor,Partial Differential Equations II: Qualitative studies of linear equations.Applied Mathematical Sciences. Springer New York, 2010

  27. [35]

    J. Wei, S. Yan, Infinitely many solutions for the prescribed scalar curvature problem onS N , J. Funct. Anal. 258 (9) (2010) 3048–3081

  28. [36]

    Wu, Solutions of the 2D quasi-geostrophic equation in H¨ older spaces

    J. Wu, Solutions of the 2D quasi-geostrophic equation in H¨ older spaces. Nonlinear Anal., 62(4) (2005), 579–594. ´Angel Castro Instituto de Ciencias Matem ´aticas, Consejo Superior de Investigaciones Cient ´ıficas, 28049 Madrid, Spain Email address:angel castro@icmat.es Anton...

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