The Nehari manifold for indefinite Kirchhoff problem with Caffarelli-Kohn-Nirenberg type critical growth
Pith reviewed 2026-05-25 16:09 UTC · model grok-4.3
The pith
At least two positive solutions exist for suitable parameters in an indefinite nonlocal Kirchhoff problem with critical growth.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
Using constrained minimization on the Nehari manifold associated with the energy functional, the authors establish the existence of at least two positive solutions to the problem for suitable positive values of the parameters λ and μ.
What carries the argument
The Nehari manifold, the set of functions u where the derivative of the functional in the direction of u vanishes, on which minimization yields critical points of the original functional.
Load-bearing premise
The specific choice of the critical exponent p together with the range 0 ≤ a < b < a+1 < N/2 ensures that the embeddings and Palais-Smale conditions hold for the functional.
What would settle it
A concrete counterexample where, for λ and μ in the claimed suitable range, the constrained minimization on the Nehari manifold produces at most one positive solution would falsify the multiplicity result.
read the original abstract
In this paper we study the following class of nonlocal {problems} involving Caffarelli-Kohn-Nirenberg type critical growth \begin{align*} L(u)&-\lambda h(x)|x|^{-2(1+a)}u=\mu f(x)|u|^{q-2}u+|x|^{-pb}|u|^{p-2}u\;\; \text{in } \mathbb R^N, \end{align*} where $h(x)\geq 0$, $f(x)$ is a continuous function which may change sign, $\lambda, \mu$ are positive real parameters and $1<q<2$, $4< p=2N/[N+2(b-a)-2]$, $0\leq a<b<a+1<N/2$, $N\geq 3$. Here $$ L(u)=-M\left(\int_{\mathbb R^N} |x|^{-2a}|\nabla u|^2dx\right)\mathrm {div}(|x|^{-2a}\nabla u) $$ and the function $M:\mathbb R^+\cup \{0\} \to\mathbb R^+$ is exactly as in the Kirchhoff model, given by $M(t)=\alpha+\beta t$, $\alpha, \beta>0$. Using the idea {of the constrained minimization on} Nehari manifold we show the existence of at least two positive solutions for suitable choices of $\lambda$ and $\mu$.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The manuscript studies a nonlocal Kirchhoff-type problem with an indefinite linear term and Caffarelli-Kohn-Nirenberg critical growth. It claims to prove the existence of at least two positive solutions via constrained minimization on the Nehari manifold N = {u ≠ 0 : ⟨I'(u), u⟩ = 0} for suitable positive parameters λ and μ, under the restrictions 0 ≤ a < b < a + 1 < N/2, 1 < q < 2, and p = 2N/[N + 2(b - a) - 2] with M(t) = α + βt.
Significance. If the details hold, the work applies standard Nehari-manifold techniques to a nonlocal setting with weighted critical nonlinearity and an indefinite term, which may be of interest for multiplicity results in variational PDEs. The parameter restrictions are chosen to secure the required embeddings and manifold geometry, but the significance hinges on whether the second critical level remains below the compactness threshold.
major comments (1)
- [Abstract and the section establishing the second critical point on N] The range 0 ≤ a < b < a + 1 < N/2 and the exact choice of p are invoked to obtain continuous embedding into the weighted space and to set up the geometry of N, but no explicit argument is given showing that the second minimax value on N lies strictly below (1/N) times the best constant in the CKN embedding (adjusted for the weights). With the Kirchhoff quartic term and the indefinite λ-term present, this control is load-bearing for the Palais-Smale condition at the second critical point; without it the second solution on N may not be recovered.
minor comments (1)
- [Abstract] The abstract states that f(x) may change sign but does not clarify how the sign-changing behavior interacts with the choice of μ in the existence intervals.
Simulated Author's Rebuttal
We thank the referee for the careful reading of our manuscript and for highlighting this important point regarding the control of the second critical level. We address the comment below.
read point-by-point responses
-
Referee: [Abstract and the section establishing the second critical point on N] The range 0 ≤ a < b < a + 1 < N/2 and the exact choice of p are invoked to obtain continuous embedding into the weighted space and to set up the geometry of N, but no explicit argument is given showing that the second minimax value on N lies strictly below (1/N) times the best constant in the CKN embedding (adjusted for the weights). With the Kirchhoff quartic term and the indefinite λ-term present, this control is load-bearing for the Palais-Smale condition at the second critical point; without it the second solution on N may not be recovered.
Authors: We agree that an explicit argument establishing c_2 < (1/N) S_{a,b} (with S_{a,b} the best constant in the weighted CKN embedding) is necessary to rigorously verify the Palais-Smale condition at the second critical level, especially given the presence of the quartic Kirchhoff term and the indefinite linear term. While the geometry of the Nehari manifold N and the existence of two distinct points u_1, u_2 on N for small λ, μ are established in Section 3 using the given restrictions on a, b, p and the form M(t) = α + βt, the strict inequality for the second minimax value is used implicitly via the smallness of λ and μ but not spelled out in detail. In the revised manuscript we will insert a new lemma immediately after the definition of c_2 that provides the required estimate: by choosing λ and μ sufficiently small (depending on α, β, N, a, b), one obtains c_2 < (1/N) S_{a,b} by comparing with the unperturbed functional and using the continuity of the embedding H^{1,2}_a(ℝ^N) ↪ L^p(|x|^{-pb} dx). This will confirm that the second solution is recovered via the constrained minimization. Revision will be made accordingly. revision: yes
Circularity Check
No significant circularity; standard variational methods on new functional
full rationale
The derivation applies the established Nehari manifold constrained minimization technique to the energy functional associated with the given nonlocal Kirchhoff equation under the stated parameter ranges for a, b, p, q, λ, μ. These ranges are external assumptions chosen to guarantee continuous embeddings into weighted Sobolev spaces and the geometry needed for the manifold (global minimizer plus second critical point via fibering or mountain-pass). No equation or existence claim reduces by definition to its own inputs, no fitted parameter is relabeled as a prediction, and no load-bearing step rests on a self-citation chain. The result is obtained by direct application of known tools to the new problem, making the paper self-contained against external benchmarks.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption The functional satisfies the required geometry and Palais-Smale condition on the Nehari manifold when p equals the stated critical exponent and the parameter ranges hold.
Lean theorems connected to this paper
-
IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
Using the idea of the constrained minimization on Nehari manifold we show the existence of at least two positive solutions...
-
IndisputableMonolith/Foundation/AlexanderDuality.leanalexander_duality_circle_linking unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
p = 2N / [N + 2(b - a) - 2] ... 0 ≤ a < b < a + 1 < N/2
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
Works this paper leans on
-
[1]
C. O. Alves, F. J. S. A. Corrˆ ea, T. F. Ma, Positive solutio ns for a quasilinear elliptic equation of Kirchho ff type, Comput. Math. Appl. 49 (2005) 85-93
work page 2005
-
[2]
Arosio, Averaged evolution equations
A. Arosio, Averaged evolution equations. The Kirchho ff string and its treatment in scales of Banach spaces, in: Func tional Analytic Methods in Complex Analysis and Applications to Partial Di fferential Equations, Trieste, 1993, World Sci. Publ., River Edge, NJ, (1995) 220254
work page 1993
- [3]
-
[4]
B. Barrios, E. Colorado, A. de Pablo, U. S´ anchez, U, On some critical problems for the fractional Laplacian operator, J. Differential Equations 251 (2012) 6133-6162
work page 2012
-
[5]
V . Bouchez, M. Willem, Extremal functions for the Ca ffarelliKohnNirenberg inequalities: a simple proof of the sy mmetry, J. Math. Anal. Appl. 352 (2009) 293-300
work page 2009
- [6]
-
[7]
L. Ca ffarelli, R. Kohn, L. Nirenberg, First order interpolation in equalities with weights, Compositio Math. 53 (1984) 259-27 5
work page 1984
-
[8]
F. Catrina, Z. Q. Wang, On the Ca ffarelli-Kohn-Nirenberg Inequalities: Sharp Constants, Ex istence (and Nonexistence), and Symmetry of Extremal Functions, Comm. Pure Appl. Math. 54 (2001) 0229-0 258
work page 2001
-
[9]
J. Chabrowski, D. G. Costa, On existence of positive solu tions for a class of Ca ffarelli-Kohn-Nirenberg type equations, Colloq. Math. 120 (2010) 43-62
work page 2010
-
[10]
C. Chen, L. Chen, Z. Xiu, Existence of nontrivial soluti ons for singular quasilinear elliptic equations on RN , Comput. Math. Appl. 65 (2013) 1909-1919
work page 2013
-
[11]
K. S. Chou, C. W. Chu, On the best constant for a weighted S obolev-Hardy inequality, J. London Math. Soc. (2) 48 (1993) 137-151
work page 1993
-
[12]
G. M. Figueiredo, Existence of a positive solution for a Kirchhoff problem type with critical growth via truncation argument, J. Math. Anal. Appl. 401 (2013) 706–713
work page 2013
-
[13]
G. M. Figueiredo, M. B. Guimar˜ aes, R. da S. Rodrigues, S olutions for a Kirchhoff equation with weight and nonlinearity with subcritical and critical Caffarelli-Kohn-Nirenberg growth, Proc. Edinb. Math. Soc. (2) , 59 (2016) 925-944
work page 2016
-
[14]
M. B. Guimar˜ aes, R. da S. Rodrigues, Existence of solut ions for Kirchho ff equations involving p-linear and p-superlinear therms and with critical growth, Electronic J. of Di fferential Equations 113-14 (2016) 1-14
work page 2016
-
[15]
L. Haidong, L. Zhao, Nontrivial solutions for a class of critical elliptic equations of Ca ffarelli–Kohn–Nirenberg type, J. Math. Anal. Appl., 404 (2013) 317–325
work page 2013
-
[16]
Kirchho ff, Mechanik, Teubner, Leipzig (1883)
G. Kirchho ff, Mechanik, Teubner, Leipzig (1883)
-
[17]
G. Li, S. Peng, Remarks on elliptic problems involving t he Caffarelli-Kohn-Nirenberg inequalities, Proc. Amer. math. So c. 136 (2008) 1221- 1228
work page 2008
-
[18]
Lions, The concentration-compactness principl e in the calculus of variations
P .-L. Lions, The concentration-compactness principl e in the calculus of variations. The limit case. II, Rev. Mat. Iberoamericana 1 (1985) 45-121
work page 1985
-
[19]
J.-L. Lions, On some quations in boundary value problem s of mathematical physics, in: Contemporary Developments i n Continuum Mechan- ics and Partial di fferential Equations, Proc. Internat. Sympos., Inst. Mat. Un iv. Fed. Rio de Janeiro, Rio de Janeiro, 1977, in: North-Holl and Math. Stud., vol.30, North-Holland, Amsterdam (1978) 284- 346
work page 1977
-
[20]
Naimen, The critical problem of Kirchho ff type elliptic equations in dimension four, J
D. Naimen, The critical problem of Kirchho ff type elliptic equations in dimension four, J. Di fferential Equations 257 (2014) 1168-1193
work page 2014
-
[21]
Z. Xiu, C. Chen, Existence of multiple solutions for sin gular elliptic problems with nonlinear boundary condition s, J. Math. Anal. Appl. 410 (2014) 625-641
work page 2014
-
[22]
S. Zhu, C. Chen, H. Y ao, Existence of multiple solutions for a singular quasilinear elliptic equation in RN , Comput. Math. Appl. 62 (2011) 4525-4534. 21
work page 2011
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.