REVIEW 1 major objections 5 minor 43 references
A new approach to the Monge-Amp\`ere eigenvalue problem
T0 review · 1 major / 5 minor · reviewed 2026-08-15 · deepseek-v4-flash
Pith's one-line read For any non-pluripolar measure, a Monge-Ampère eigenvalue pair is unique up to a positive constant.
desk verdict A real but repairable gap in Theorem 3.8; the envelope method is genuinely new and the paper deserves peer review after a major revision. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
The load-bearing mechanism is the plurisubharmonic envelope $P(h)=(\sup\{v\in\mathrm{PSH}(\Omega): v\le h\})^*$, applied to $\min(u-\psi,0)$ to combine a solution and a subsolution into a supersolution whose Monge-Ampère measure is concentrated on the contact set $\{v=u-\psi\}$. Lemma 3.4 then uses the variational definition of $\lambda_1$ to show that any supersolution at the exact quotient $\lambda_1$ is a true solution: integrating the supersolution inequality against $(-u)$ forces equality because $E(u)\le\lambda_1^n I_\mu(u)$ and $\lambda_1\le E/I_\mu$. This partial sublinearization is the step that lets the argument run without a smooth solution to linearize around.
What would settle it
Assume there is a $\psi$ satisfying $(dd^c\psi)^n\ge(-\lambda_1\psi)^n\mu$ strictly on a set of positive $\mu$-measure, construct $u$ by solving $(dd^c u)^n=(-\lambda_1\psi)^n\mu$, and test whether $(dd^c u)^n\le(-\lambda_1 u)^n\mu$ holds on the contact set $\{u=\psi\}$; a single such measure would show the general-case uniqueness assertion needs an additional hypothesis.
Extended reading notes
Core claim
The paper's central theorem states that if $(\lambda,\varphi)$ solves $(dd^c u)^n=(-\lambda u)^n\mu$ with $u$ in the Cegrell finite-energy class $E^1(\Omega)$, then $\lambda=\lambda_1(\mu)=\inf\{E(u)/I_\mu(u): u\in E^1(\Omega)\setminus\{0\}\}$, and any $\psi\in E^1(\Omega)\setminus\{0\}$ satisfying $(dd^c\psi)^n\ge(-\lambda\psi)^n\mu$ is in fact a solution and equals $c\varphi$ for some $c>0$. This removes the smoothness assumptions on the domain and the density that earlier uniqueness results required; $\mu$ only has to vanish on pluripolar sets. In particular the inequality cannot be strict: a function that merely lies on the subsolution side at the critical quotient is already an eigenfunction. When $I_\mu$ is continuous on the energy sublevel sets, the same framework proves existence and gives an iterative approximation of the eigenpair.
Load-bearing premise
The proof of the general uniqueness statement in the general-case part of Theorem 3.8 rests on the premise that the auxiliary function $u$ solving $(dd^c u)^n=(-\lambda\psi)^n\mu$ with $u\ge\psi$ is a supersolution at $\lambda_1$; Lemma 3.4 can convert a supersolution into a solution, but not a mere subsolution, so if that inequality is missing the uniqueness conclusion for arbitrary non-pluripolar measures is not established.
Editorial extensions
If this is right
- The first eigenvalue $\lambda_1(\mu)$ is a genuine invariant of the pair $(\Omega,\mu)$: no second eigenvalue can exist, and all eigenfunctions are proportional.
- Lions' original strategy is valid in this generality: $\lambda_1$ is the largest $\lambda$ for which $(dd^c u)^n=(1-\lambda u)^n\mu$ has a finite-energy solution.
- When $I_\mu$ is continuous on each energy sublevel set, the iteration $(dd^c u_{k+1})^n=R(u_k)(-u_k)^n\mu$ with $R(u_k)=E(u_k)/I_\mu(u_k)$ converges from any nonzero finite-energy start to a solution of the eigenvalue problem.
- The same uniqueness, variational formula, and iterative convergence hold for the complex Hessian operators $H_m(u)=(dd^c u)^m\wedge\beta^{n-m}$ on $m$-hyperconvex domains.
- For the real Monge-Ampère operator on a bounded convex domain, the eigenvalue pair is unique with no regularity hypothesis, and existence holds for measures that are the real Monge-Ampère measure of a continuous convex function, and more generally for any measure integrating a negative convex function.
Reading between the lines
- Because the proof only needs envelopes and the variational definition, the same partial-sublinearization recipe may apply to other fully nonlinear Dirichlet eigenvalue problems that admit a comparison principle.
- The quotient $\lambda_1(\mu)$ behaves like a spectral radius for a nonlinear operator, so one could ask whether eigenfunction level sets encode the geometry of the contact set when $\mu$ is purely singular.
- The monotonicity of $E(u_k)$ along the iteration suggests a stable numerical method for measures without densities; testing it on singular measures could show how close the continuity assumption on $I_\mu$ is to being necessary.
Signed reviews
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper studies the complex Monge-Ampère eigenvalue problem in bounded hyperconvex domains for a non-pluripolar positive Borel measure μ. The central results are: a Rayleigh-quotient formula for the eigenvalue λ1(μ) in terms of the Cegrell energy E and the functional Iμ(u)=∫(-u)^{n+1}dμ; uniqueness of eigenfunctions in E1(Ω) up to positive constants with no regularity assumption on μ; an existence and approximation result via an iterative scheme under a continuity assumption on Iμ; a general Dirichlet problem with non-monotone right-hand side; and analogues for complex Hessian and real Monge-Ampère operators. The method is based on plurisubharmonic envelopes and a comparison/supersolution argument rather than on linearization around a smooth solution.
Significance. If the main theorem is correct, the paper gives a substantial generalization of earlier smooth-data results of Lions and of Badiane–Zeriahi: uniqueness of eigenfunctions and a variational formula are obtained for arbitrary non-pluripolar measures, with no boundary or density assumptions. The envelope method is a genuinely new tool in this problem, and the extensions to Hessian and real operators are natural and potentially useful. The variational formula is derived rather than assumed, so there is no circularity in the definition of the eigenvalue. The absolutely continuous case of the uniqueness proof appears sound, as does the Rayleigh quotient argument. However, as detailed below, the general non-absolutely-continuous case of the uniqueness proof contains a load-bearing gap that, as written, invalidates Theorem 1.1's full uniqueness claim and the subsequent corollaries.
major comments (1)
- [§3.2, proof of Theorem 3.8, general case] The step 'It thus follows from Lemma 3.4 that (λ,u) solves (MA_{μ,λ})' is not justified. The constructed function u satisfies (dd^c u)^n = (−λψ)^n μ. Since u≥ψ and both are negative, (−λψ)^n μ ≥ (−λu)^n μ, so u is a subsolution of (MA_{μ,λ}), not a supersolution. Lemma 3.4, the only tool invoked to upgrade u to a solution, explicitly requires the supersolution inequality (dd^c u)^n ≤ (−λu)^n μ. Consequently the identity E(u)/Iμ(u)=λ^n, which is used to obtain the contradiction with the positive measure σ, is not established. This is the precise step that removes the absolute-continuity assumption on (dd^c ψ)^n, so Theorem 1.1, Corollary 3.9, and the real-variable Theorem 7.5 are not proved as written. The gap appears localized and repairable: since (dd^c u)^n = (−λψ)^n μ ≪ μ, the first, absolutely continuous case of Theorem 3.8 can be applied to the subsolution u, yielding that u is a solution and u=cφ; one then still needs to close the argument to identify ψ with a multiple of φ. The authors should supply the missing reasoning carefully.
minor comments (5)
- [§2.1] There is a typo: 'pluribubharmonic' should be 'plurisubharmonic'.
- [§2.2] The phrase 'in the sens of Borel measures' appears twice; 'sens' should be 'sense'.
- [§3.1, proof of Theorem 3.5] In the line 'E(u)−γ1^n Iμ(u)=0≤E(v)−μ1 Iμ(v)', the symbol 'μ1' should presumably be 'γ1'.
- [§4.1, proof of Theorem 4.1] The word 'leaded' in 'which leaded to (4.2)' should be 'led'.
- [§6] Theorem 6.1 is an advertised extension to complex Hessian operators, but its proof is only a sentence saying that the entire proof can be adapted and 'details are left to the reader'. For a refereed journal, the adaptation should be written out, at least in outline, so that the reader can verify that the envelope lemmas and the comparison arguments carry over without new hypotheses.
Circularity Check
No circularity: the Rayleigh quotient formula is a definition and is proved to coincide with any eigenvalue; the cited prior results are independent published theorems, and the questionable step in Theorem 3.8 is a derivation gap rather than a circular reduction.
full rationale
The paper's central claim is not circular. The quantity λ1(μ) is introduced in Definition 3.1 as the infimum of the Rayleigh quotient E(u)/Iμ(u), and Theorem 3.5 proves separately, via envelope and domination arguments, that any solution of the eigenvalue problem has λ = λ1(μ). The eigenfunction uniqueness result in Theorem 3.8 is then proved from that variational identity and from comparison/envelope lemmas; it does not define the eigenvalue in terms of the eigenfunction. The dependence on prior work by the same authors ([GLZ19], [Zer25], [BZ23], [ÅCLR24]) is real but does not amount to circularity: those results are published, parameter-free theorems with stated assumptions that do not include the present eigenvalue claim, and they are used as tools rather than as the conclusion being derived. The one logically problematic passage is in the general case of Theorem 3.8, where the authors construct u with (ddcu)^n = (−λψ)^n μ, observe u is a subsolution, and then write 'It thus follows from Lemma 3.4 that (λ,u) solves (MAμ,λ)'; Lemma 3.4 converts supersolutions into solutions, not subsolutions. This is a genuine gap in the written proof, but it is a correctness or completeness issue, not an instance of circularity: the missing inequality (ddcu)^n ≤ (−λu)^n μ is not supplied by any definitional identity or fitted input, and the gap appears repairable by applying the previously proved absolutely continuous case to u. Under the hard rules, derivation gaps without an equation-to-equation or input-to-output identity do not raise the circularity score.
Assumptions & free parameters
assumptions (5)
- standard math The Bedford-Taylor theory of the complex Monge-Ampère operator on bounded hyperconvex domains and the Cegrell class E^1(Ω).
- standard math The plurisubharmonic envelope theorem for quasi-continuous functions (Theorem 2.8), cited from [GLZ19].
- standard math Existence of solutions to (dd^c u)^n = ν for measures ν satisfying the a priori estimate in [˚ACC12, Theorem A].
- standard math Known solvability of the real Monge-Ampère equation MR(u)=ν with ν(D)<∞ (Theorem 7.2, cited to [Har06] and others).
- standard math The comparison principle and domination principle for the complex Monge-Ampère operator in E^1.
Cite this review
Pith. "Pith review of A new approach to the Monge-Amp\`ere eigenvalue problem." pith.science (2026). https://pith.science/paper/5ZA7VMA6
@misc{pith2026250718409,
author = {Pith},
title = {Pith review of: A new approach to the Monge-Amp\`ere eigenvalue problem},
year = {2026},
howpublished = {\url{https://pith.science/paper/5ZA7VMA6}},
note = {Machine review of arXiv:2507.18409}
}
abstract
We study the eigenvalue problem for the complex Monge-Amp\`ere operator in bounded hyperconvex domains in $\C^n$, where the right-hand side is a non-pluripolar positive Borel measure. We establish the uniqueness of eigenfunctions in the finite energy class introduced by Cegrell, up to positive multiplicative constants, and provide a Rayleigh quotient type formula for computing the eigenvalue. Under a natural continuity assumption on the measure, we further show that both the eigenvalue and eigenfunctions can be obtained via an iterative procedure starting from any negative finite energy function. Our approach relies on the fine properties of plurisubharmonic envelopes, which allow a partial sublinearization of the nonlinear problem. As far as we know, this method is new, even in the linear case, and not only yields new results but also significantly simplifies existing arguments in the literature. Moreover, it extends naturally to the setting of complex Hessian operators. Finally, by translating our results from the complex Monge-Amp\`ere setting via a logarithmic transformation, we also obtain several interesting analogues for the real Monge-Amp\`ere operator.
Reference graph
Works this paper leans on
-
[1]
On Dirichlet 's principle and problem
Per hag, Urban Cegrell, and Rafa Czy \.z . On Dirichlet 's principle and problem. Math. Scand. , 110(2):235--250, 2012
work page 2012
-
[2]
Per hag, Rafa Czy \.z , Chinh H. Lu, and Alexander Rashkovskii. Kiselman minimum principle and rooftop envelopes in complex Hessian equations. Math. Z. , 308(4):24, 2024. Id/No 70
work page 2024
-
[3]
Per hag, Rafa Czy \.z , Chinh H. Lu, and Alexander Rashkovskii. Geodesic connectivity and rooftop envelopes in the Cegrell classes. Math. Ann. , 391(3):3333--3361, 2025
work page 2025
-
[4]
Inverse iteration for the Monge - Amp \`e re eigenvalue problem
Farhan Abedin and Jun Kitagawa. Inverse iteration for the Monge - Amp \`e re eigenvalue problem. Proc. Am. Math. Soc. , 148(11):4875--4886, 2020
work page 2020
-
[5]
A. D. Alexandrov and V. A. Zalgaller. Intrinsic Geometry of Surfaces. Translations of Mathematical Monographs, Amer. Math. Soc , 15, 1967
work page 1967
-
[6]
Robert J. Berman and Bo Berndtsson. Real Monge - Amp \`e re equations and K \"a hler - Ricci solitons on toric log Fano varieties. Ann. Fac. Sci. Toulouse, Math. (6) , 22(4):649--711, 2013
work page 2013
-
[7]
Berman, S \'e bastien Boucksom, Vincent Guedj, and Ahmed Zeriahi
Robert J. Berman, S \'e bastien Boucksom, Vincent Guedj, and Ahmed Zeriahi. A variational approach to complex Monge - Amp \`e re equations. Publ. Math., Inst. Hautes \'E tud. Sci. , 117:179--245, 2013
work page 2013
-
[8]
Plurisubharmonic functions with weak singularities
Slimane Benelkourchi, Vincent Guedj, and Ahmed Zeriahi. Plurisubharmonic functions with weak singularities. In Complex analysis and digital geometry. Proceedings from the Kiselmanfest, Uppsala, Sweden, May 2006 on the occasion of Christer Kiselman's retirement , pages 57--74. Uppsala: Univ. Uppsala, 2009
work page 2006
Show all 43 references
-
[9]
Estimates for the complex Monge - Amp \`e re operator
Zbigniew B ocki. Estimates for the complex Monge - Amp \`e re operator. Bull. Pol. Acad. Sci., Math. , 41(2):151--157, 1993
1993
-
[10]
Interior regularity of the degenerate Monge-Ampère equation
Zbigniew B ocki. Interior regularity of the degenerate Monge-Ampère equation. Bull. Aust. Math. Soc. 68(1): 81--92, 2003
2003
-
[11]
Weak solutions to the complex Hessian equation
Zbigniew B ocki. Weak solutions to the complex Hessian equation. Ann. Inst. Fourier , 55(5):1735--1756, 2005
2005
-
[12]
Eric Bedford and B. A. Taylor. The Dirichlet problem for a complex Monge - Amp \`e re equation. Invent. Math. , 37:1--44, 1976
1976
-
[13]
Eric Bedford and B. A. Taylor. Fine topology, S ilov boundary, and (dd^c)^n . J. Funct. Anal. , 72(2):225--251, 1987
1987
-
[14]
The H \"o lder continuous subsolution theorem for complex Hessian equations
Amel Benali and Ahmed Zeriahi. The H \"o lder continuous subsolution theorem for complex Hessian equations. J. \'E c. Polytech., Math. , 7:981--1007, 2020
2020
-
[15]
The eigenvalue problem for the complex Monge - Amp \`e re operator
Papa Badiane and Ahmed Zeriahi. The eigenvalue problem for the complex Monge - Amp \`e re operator. J. Geom. Anal. , 33(12):44, 2023. Id/No 367
2023
-
[16]
A variational approach to the eigenvalue problem for complex Hessian operators
Papa Badiane and Ahmed Zeriahi. A variational approach to the eigenvalue problem for complex Hessian operators. In Nonlinear analysis, geometry and applications. Proceedings of the third NLAGA-BIRS symposium, AIMS-Mbour, Senegal, August 21--27, 2023 , pages 227--256. Cham: Bir...
2023
-
[17]
Pluricomplex energy
Urban Cegrell. Pluricomplex energy. Acta Math. , 180(2):187--217, 1998
1998
-
[18]
The general definition of the complex Monge - Amp \`e re operator
Urban Cegrell. The general definition of the complex Monge - Amp \`e re operator. Ann. Inst. Fourier , 54(1):163--184, 2004
2004
-
[19]
A general D irichlet problem for the complex M onge- A mp\`ere operator
Urban Cegrell. A general D irichlet problem for the complex M onge- A mp\`ere operator. Ann. Polon. Math. , 94(2):131--147, 2008
2008
-
[20]
Toric pluripotential theory
Dan Coman, Vincent Guedj, Sibel Sahin, and Ahmed Zeriahi. Toric pluripotential theory. Ann. Pol. Math. , 123:215--242, 2019
2019
-
[21]
The equation of complex Monge - Amp \`e re type and stability of solutions
Urban Cegrell and S awomir Ko odziej. The equation of complex Monge - Amp \`e re type and stability of solutions. Math. Ann. , 334(4):713--729, 2006
2006
-
[22]
The Eigenvalue Problem for the Complex Hessian Operator on m - Pseudoconvex Manifolds
Jianchun Chu, Yaxiong Liu, and Nicholas McCleerey. The Eigenvalue Problem for the Complex Hessian Operator on m - Pseudoconvex Manifolds . Preprint, arXiv :2402.03098, 2024
2024 arXiv
-
[23]
The continuous subsolution problem for complex Hessian equations
Mohamad Charabati and Ahmed Zeriahi. The continuous subsolution problem for complex Hessian equations. Indiana Univ. Math. J. , 73(5):1639--1688, 2024
2024
-
[24]
An inequality for mixed Monge - Amp \`e re measures
S awomir Dinew. An inequality for mixed Monge - Amp \`e re measures. Math. Z. , 262(1):1--15, 2009
2009
-
[25]
A priori estimates for complex Hessian equations
S awomir Dinew and S awomir Ko odziej. A priori estimates for complex Hessian equations. Anal. PDE , 7(1):227--244, 2014
2014
-
[26]
Eleonora Di Nezza, Vincent Guedj, and Chinh H. Lu. Finite entropy vs finite energy. Comment. Math. Helv. , 96(2):389--419, 2021
2021
-
[27]
The Monge - Amp \`e re equation and its applications
Alessio Figalli. The Monge - Amp \`e re equation and its applications . Zur. Lect. Adv. Math. Z \"u rich: European Mathematical Society (EMS), 2017
2017
-
[28]
Vincent Guedj and Chinh H. Lu. Uniform estimates: from Yau to Kolodziej . Preprint, arXiv :2502.02313, 2025
2025 arXiv
-
[29]
Lu, and Ahmed Zeriahi
Vincent Guedj, Chinh H. Lu, and Ahmed Zeriahi. Plurisubharmonic envelopes and supersolutions. J. Differ. Geom. , 113(2):273--313, 2019
2019
-
[30]
Guti \'e rrez
Cristian E. Guti \'e rrez. The Monge - Amp \`e re equation , volume 89 of Prog. Nonlinear Differ. Equ. Appl. Basel: Birkh \"a user/Springer, 2nd edition edition, 2016
2016
-
[31]
The Dirichlet problem for the Monge - Amp \`e re equation in convex (but not strictly convex) domains
David Hartenstine. The Dirichlet problem for the Monge - Amp \`e re equation in convex (but not strictly convex) domains. Electron. J. Differ. Equ. , 2006:9, 2006. Id/No 138
2006
-
[32]
A remark on the H \"o lder regularity of solutions to the complex Hessian equation
S awomir Ko odziej and Ngoc Cuong Nguyen. A remark on the H \"o lder regularity of solutions to the complex Hessian equation. J. Funct. Anal. , 289(6):17, 2025. Id/No 111005
2025
-
[33]
Nam Q. Le. The eigenvalue problem for the Monge - Amp \`e re operator on general bounded convex domains. Ann. Sc. Norm. Super. Pisa, Cl. Sci. (5) , 18(4):1519--1559, 2018
2018
-
[34]
Nam Q. Le. Convergence of an iterative scheme for the Monge - Amp \`e re eigenvalue problem with general initial data. Preprint, arXiv :2006.06564, 2020
2006
-
[35]
Two remarks on Monge - Amp \`e re equations
Pierre-Louis Lions. Two remarks on Monge - Amp \`e re equations. Ann. Mat. Pura Appl. (4) , 142:263--275, 1985
1985
-
[36]
Chinh H. Lu. A variational approach to complex Hessian equations in \( C ^n\) . J. Math. Anal. Appl. , 431(1):228--259, 2015
2015
-
[37]
A Dirichlet principle for the complex Monge -- Amp \`e re operator
Leif Persson. A Dirichlet principle for the complex Monge -- Amp \`e re operator. Ark. Mat. , 37(2):345--356, 1999
1999
-
[38]
Local geodesics for plurisubharmonic functions
Alexander Rashkovskii. Local geodesics for plurisubharmonic functions. Math. Z. , 287(1-2):73--83, 2017
2017
-
[39]
Jeffrey Rauch and B. A. Taylor. The Dirichlet problem for the multidimensional Monge - Amp \`e re equation. Rocky Mt. J. Math. , 7:345--364, 1977
1977
-
[40]
Degenerate complex Monge - Amp \`e re equations with non- Kaehler forms in bounded domains
Mohammed Salouf. Degenerate complex Monge - Amp \`e re equations with non- Kaehler forms in bounded domains. Indiana Univ. Math. J. , 74(1):131--156, 2025
2025
-
[41]
Michael E. Taylor. Partial differential equations. III : Nonlinear equations. , volume 117 of Appl. Math. Sci. New York, NY: Springer, 2nd ed. edition, 2011
2011
-
[42]
On a real Monge - Amp \`e re functional
Kaising Tso. On a real Monge - Amp \`e re functional. Invent. Math. , 101(2):425--448, 1990
1990
-
[43]
An iterative approach to the complex monge--amp \`e re eigenvalue problem
Ahmed Zeriahi. An iterative approach to the complex monge--amp \`e re eigenvalue problem. In Annales Polonici Mathematici , pages 1--14. Instytut Matematyczny Polskiej Akademii Nauk, 2025
2025
Reviewed August 15, 2026 · model on record in the stance chip above.
Discussion (0). Continue with ORCID to comment.