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REVIEW 3 major objections 4 minor 33 references

On Second-Order $L^\infty$ Variational Problems with Lower-Order Terms

T0 review · 3 major / 4 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read For second-order supremal functionals, the Euler-Lagrange analogue is a third-order fully nonlinear PDE, and the Dirichlet problem admits generalised D-solutions.

desk verdict A genuine extension of the second-order L-infinity programme with a solid D-solution section, but the 1D absolute-minimiser proof as written does not work. read the letter →

arxiv 2412.11701 v2 pith:IOQ424DM submitted 2024-12-16 math.AP

classification math.AP MSC 35J4735J6035D3035A15
keywords calculusofvariationsinL∞supremalfunctionalsabsoluteminimisersvariationalPDEsfullynonlinearPDED-solutionsYoungmeasuresHessian
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 seeks to complete the second-order L∞ calculus of variations for supremands depending on the full second-order jet: given E∞(u,O)=ess sup_O H(·,u,Du,D²u), it establishes existence of global minimisers under Dirichlet data, of absolute minimisers in one dimension, and derives the third-order fully nonlinear PDE H_X(J²u):D(H(J²u))⊗D(H(J²u))=0 as the Euler-Lagrange analogue. It proves that C³ absolute minimisers satisfy this PDE classically, and that under a structural factorisation H=h(·,·,·,XᵀX) with monotonicity along the identity direction, the Dirichlet problem for the expanded third-order equation has generalised solutions in the D-sense. If correct, the theory provides a PDE that canonically belongs to the supremal functional and a rigorous generalised-solution framework where classical, weak, and viscosity notions do not apply.

What carries the argument

The load-bearing object is the third-order fully nonlinear operator A²∞u, the contraction of the Hessian-derivative of the supremand with the outer product of the gradient of the composed supremand H(J²u). Its expanded form A∞(J²u,D³u)=0 is the equation for which generalised solutions are defined. The proof rests on three mechanisms: shifted L^p approximations E_p=(∫(M+H)^p)^{1/p}−M, which select a preferred minimiser while handling sign-changing H; a variational lemma that uses a max-differentiation theorem on the one-sided derivatives of the supremal functional to obtain inequalities at points where H(J²u) is maximal or minimal; and the D-solution framework, in which the third derivative is a Young-measure-valued diffuse derivative and the equation is required to hold on the reduced support of that measure. Feeding that framework is the category-method solvability of the implicit equation H(J²u)=C, obtained by prescribing the eigenvalues of D²uᵀD²u and using the identity-direction monotonicity of h.

What would settle it

Set n=1, take H(X)=X², and choose first-order boundary data g with g″ non-constant. The unique absolute minimiser for ‖u″‖∞ is piecewise quadratic with one jump in u″; compute its diffuse third derivative from difference quotients and check the reduced-support condition sup_{Z∈supp*(D³u(x))} |A∞(J²u(x),Z)|=0. Any point where the support of D³u(x) contains a third-derivative value with A∞(J²u(x),Z)≠0 would make Theorem 5.2 false for this H; if the condition holds, the D-solution notion is compatible with the known non-smooth minimiser.

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Extended reading notes

Core claim

For the supremal functional (1.1), the correct Euler-Lagrange analogue is A²∞u=0 in (1.3), and the paper proves this in two directions. Global minimisers exist by passing to the limit p→∞ in shifted L^p functionals (3.1), under coercivity and level-convexity; in dimension one the L^p-selected minimiser is absolute. If an absolute minimiser is C³, it solves (1.3) classically, via a new argument using radial test functions and one-sided max/min inequalities; the derivation of (1.3) from the L^p Euler-Lagrange equations is formal but defines the candidate. The PDE is then studied independently of the variational problem: for H=h(·,·,·,XᵀX) with h strictly increasing along t↦tI and bounded at δ₀I, the implicit equation H(J²u)=C has infinitely many $W^{{2,∞}}$ solutions matching g and Dg on ∂Ω, and each is a D-solution of the expanded third-order equation A∞(J²u,D³u)=0. This extends the earlier pure-Hessian second-order theory to lower-order terms with shorter proofs.

Load-bearing premise

For the generalised-solution existence theorem, the load-bearing premise is the structural assumption H(x,η,p,X)=h(x,η,p,XᵀX) with h strictly increasing along t↦tI; if a smooth supremand does not factor through XᵀX or is not monotone along identity multiples, the category-method construction of solutions to H(J²u)=C is not available and the D-solution conclusion is not established.

Editorial extensions

If this is right

  • Any C³ absolute minimiser of E∞ solves the third-order equation (1.3) classically, so regularity of the supremand immediately implies a pointwise PDE without differentiability of the functional.
  • The L^p-approximation route yields a global minimiser that in one dimension is automatically an absolute minimiser, so the selected object is locally optimal, not merely globally optimal.
  • When H factors through XᵀX and is monotone along identity multiples, the Dirichlet problem for A∞(J²u,D³u)=0 has infinitely many W^{2,∞} D-solutions for arbitrary first-order Dirichlet data.
  • The generalised-solution result subsumes and shortens the pure-Hessian second-order case, because the proof no longer has to be carried out from first principles.

Reading between the lines

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

  • The paper leaves open whether the L^p-selected minimiser is absolute in dimension two or higher; the one-dimensional proof relies on cubic Hermite interpolation on intervals, so higher-dimensional absolute minimality is the natural next target.
  • The structural factorisation H=h(·,·,·,XᵀX) suggests reading D²uᵀD²u as a Hessian metric and the identity-direction monotonicity as a trace-type growth condition; this could be tested numerically on radial solutions where the eigenvalue problem reduces to an ODE.
  • Because the shifted approximation replaces H by M+H without changing minimisers, the existence theorem is effectively invariant under adding a constant to the supremand, which simplifies numerical realisation for sign-changing H.
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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

3 major / 4 minor

Summary. The paper studies second-order L^∞ variational functionals E∞(u,O)=ess sup_O H(·,u,Du,D²u) with lower-order terms. It claims existence of global minimisers under coercivity and level-convexity assumptions (Theorem 3.1), existence of absolute minimisers in one dimension (Theorem 3.4), a formal derivation of the third-order fully nonlinear PDE A²∞u=0 as the analogue of the Euler-Lagrange equation (Derivation 4.1), a rigorous proof that C³ absolute minimisers solve this PDE classically (Theorem 4.3), and existence of generalised D-solutions to the corresponding Dirichlet problem under a structural ansatz on H (Theorem 5.2). The paper generalises the pure-Hessian results of [26] and offers a streamlined treatment of the D-solution existence via the Baire-category method and the Dacorogna–Marcellini theory of implicit PDEs.

Significance. If the main claims were established, the paper would be a valuable contribution to higher-order L^∞ variational theory: it identifies the correct third-order PDE for supremal functionals with lower-order terms, provides a clean reduction of D-solution existence to known implicit-PDE machinery, and simplifies earlier proofs from [26]. The global-minimiser theorem and the D-solution theorem are substantial and appear largely sound under their stated assumptions. However, the central new variational claim — the existence of absolute minimisers in one dimension — is not proved by the argument given: the key local inequality in Theorem 3.4 does not follow from global approximate minimality. The D-solution existence is also conditional on a quite restrictive structural assumption, which should be transparently highlighted in the abstract and introduction.

major comments (3)
  1. [§3, Theorem 3.4, Eq. (3.17)] The first inequality of (3.17), Ep(up,(a,b)) ≤ 2^{-p}+Ep(up+φp,(a,b)), is not a consequence of the global approximate-minimiser property Ep(up,Ω) ≤ 2^{-p}+Ep(up+φp,Ω) together with the fact that up and up+φp agree outside (a,b). For nonnegative integrands with equal values outside (a,b), the global normalised Lp inequality does not control the local normalised Lp norms. For example, with Ω=(0,2), (a,b)=(0,1), p=2, f≡10 on (0,1), f≡10^6 on (1,2), g≡0 on (0,1), g≡10^6 on (1,2), the global inequality holds while Ep(f,(0,1))=10 > 0.25 = 2^{-2}+Ep(g,(0,1)). Since this local estimate is the only step linking the Lp approximants to the absolute-minimiser property of u∞, the proof of Theorem 3.4 is incomplete and the abstract's assertion that absolute minimisers exist when n=1 is not supported by the argument presented.
  2. [§4, Lemma 4.2] The proof of Lemma 4.2 starts from the global inequality E∞(u+ϕ,Ω)≥E∞(u,Ω) and concludes that h(t):=max_O H(·,u+tϕ,Du+tDϕ,D²u+tD²ϕ) satisfies h(t)≥h(0) for all t. This implication is false in general: if the maximum of H(J²u) over Ω\O is larger than max_O H(J²u), the global inequality holds even when h(t)<h(0). The correct argument should use the absolute-minimiser property on O itself, namely E∞(u+ϕ,O)≥E∞(u,O), which is exactly what Definition 1.1 gives for ϕ∈W^{2,∞}_0(O). The repair is immediate, but as written the proof of the lemma is incorrect.
  3. [§3, Corollary 3.3] Corollary 3.3 is a load-bearing ingredient in the proof of Theorem 3.4, since it is used to pass from the Lp approximants to E∞(u∞,(a,b)). Its proof is omitted with only a reference to [19, Lemma 5.1]. The authors should either include a full proof or state precisely how [19, Lemma 5.1] applies to the present second-order functional with lower-order terms; a reader cannot otherwise verify the diagonal lower semicontinuity step.
minor comments (4)
  1. [§5, Theorem 5.2] The abstract and introduction state that D-solutions are proved to exist, but Theorem 5.2 requires the structural assumption H(x,η,p,X)=h(x,η,p,X^T X) with h strictly increasing along t↦tI and the boundedness condition (5.3). This is substantially more restrictive than the hypotheses of Theorem 3.1 and is not satisfied by a generic C¹ supremand; the statement should be qualified accordingly.
  2. [§1, Eq. (1.11)] The summation indices in the display for A∞ include p and q, while p is also used as the gradient argument of H; this makes the formula harder to read. Consider using different letters for the summation indices or explicitly stating that p,q are dummy indices.
  3. [§3, proof of Theorem 3.4] The inequality chain in (3.17) contains a factor ((b−a)/|Ω|)^{1/p} multiplying E∞, which is not needed and seems inconsistent with the normalisation of Ep. The factor tends to 1 as p→∞, so this does not affect the conclusion, but the line should be corrected for clarity.
  4. [§4, Derivation 4.1] The formal derivation assumes H is C² and u is C⁴, while Theorem 4.3 only assumes H∈C¹ and u∈C³. The relation between the formal calculation and the rigorous theorem would be clearer if the different regularity assumptions were separated explicitly.

Circularity Check

0 steps flagged · score 1.0 of 10

No significant circularity: the PDE is derived, not assumed, and all load-bearing supporting results are external theorems or prior published lemmas with independent content.

full rationale

The paper's central derivation chain is not circular. The Aronsson-type PDE (1.3) is obtained in Derivation 4.1 by taking the formal p→∞ limit of the Euler–Lagrange equations of the Lp approximants (3.1), not by postulating the equation; the integrand H and its derivatives are the only inputs. Theorem 4.3 then proves, via Danskin's theorem and explicit radial test functions (4.6)–(4.8), that C3 absolute minimisers solve this PDE classically; this argument is self-contained apart from the standard Danskin theorem. Existence of global minimisers (Theorem 3.1) is established directly with Young measures and the extended Jensen inequality, with no fitted quantity. The D-solution existence result (Theorem 5.2) reduces to Lemma 5.1, which invokes the external Dacorogna–Marcellini theorem on singular-value problems; the step from H(J2u)=C to A∞(J2u,D3u)=0 in the D-sense uses the general differentiation theorem [20, Theorem 30]. While [19], [20], and [26] are same-author citations, they are published, parameter-free theorems with independent proofs, not restatements of the target conclusion, and no equation is defined in terms of the result it is supposed to establish. The possible gap in Theorem 3.4's subdomain inequality noted by the skeptic is a correctness concern, not a circularity: it does not amount to the conclusion being equivalent to its inputs by construction. Accordingly, the circularity score is low.

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

No empirical constants are fitted; the paper is analytic. It relies on external theorems, several from the same author's prior work, but these are established results rather than assumptions built to imply the target. The structural ansatz H=h(x,η,p,X^T X) in Section 5 is a domain hypothesis, not an invented entity.

assumptions (6)
  • domain assumption Extended Jensen inequality for level-convex functions (sublevel sets convex) in the Hessian argument.
    Used in the proof of Theorem 3.1 to pass from Young measure averages to supremal values; quoted as (3.4) and attributed to [10]. It holds for continuous level-convex functions, which the paper assumes.
  • domain assumption Dacorogna-Marcellini solvability theorem for implicit PDEs with strict subsolutions (singular value problem for Hessians).
    Lemma 5.1 relies on [15, Theorem 7.31, Remark 7.29, Corollary 7.34] to obtain infinitely many W^{2,∞} solutions of λ_i(D²u^T D²u)=f(J1u). This is a heavy external existence theorem.
  • domain assumption [20, Theorem 30]: equations of the form F(J^2u)=0 holding a.e. can be differentiated in the D-sense to obtain the differentiated system.
    Theorem 5.2 uses this to pass from H(J²u)=C a.e. to (5.11) in the diffuse sense. The theorem is by the same author and is cited as a black box.
  • domain assumption [19, Lemma 5.1]: diagonal weak lower semicontinuity of E∞ along L^p approximations.
    Corollary 3.3 is stated with proof omitted, explicitly citing [19, Lemma 5.1].
  • standard math Danskin's theorem on directional differentiability of max functions.
    Lemma 4.2 uses Danskin's theorem [16] to compute right and left derivatives of h(t)=max H(...); requires continuity of H and compactness of the max domain (closure should be used).
  • standard math Poincaré inequality on W^{2,k}_0(Ω) and sequential weak* compactness of Young measures.
    Used throughout the proof of Theorem 3.1 for a priori bounds and to extract Young measure limits from Hessians.

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Pith. "Pith review of On Second-Order $L^\infty$ Variational Problems with Lower-Order Terms." pith.science (2026). https://pith.science/paper/IOQ424DM

@misc{pith2026241211701,
  author       = {Pith},
  title        = {Pith review of: On Second-Order $L^\infty$ Variational Problems with Lower-Order Terms},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/IOQ424DM}},
  note         = {Machine review of arXiv:2412.11701}
}
abstract

In this paper we study $2$nd order $L^\infty$ variational problems, through seeking to minimise a supremal functional involving the Hessian of admissible functions as well as lower-order terms. Specifically, given a bounded domain $\Omega\subseteq \mathbb R^n$ and $\mathrm H : \Omega\times\big(\mathbb R \times\mathbb R^n \times \mathbb R^{n^{\otimes2}}_s \big) \to \mathbb R$, we consider the functional \[ \mathrm{E}_\infty(u, \mathcal{O}) :=\underset{ \mathcal{O}}{\mathrm{ess}\sup}\hspace{1mm}\mathrm H (\cdot,u,\mathrm D u,\mathrm D^2u ) , \ \ u\in W^{2,\infty}(\Omega), \ \mathcal{O} \subseteq \Omega \text{ measurable}. \] We establish the existence of minimisers subject to (first-order) Dirichlet data on $\partial \Omega$ under natural assumptions, and, when $n=1$, we also show the existence of absolute minimisers. We further derive a necessary fully nonlinear PDE of third-order which arises as the analogue of the Euler-Lagrange equation for absolute minimisers, and is given by $$ \ \ \mathrm H_{\mathrm X}(\cdot,u,\mathrm D u,\mathrm D^2u): \mathrm D\big(\mathrm H(\cdot,u,\mathrm D u,\mathrm D^2u)\big)\otimes \mathrm D\big(\mathrm H(\cdot,u,\mathrm D u,\mathrm D^2u)\big)=0\ \ \text{ in }\Omega. $$ We then rigorously derive this PDE from smooth absolute minimisers, and prove the existence of generalised D-solutions to the (first-order) Dirichlet problem. Our work generalises the key results obtained in [26] which first studied problems of this type with pure Hessian dependence only, providing at the same time considerably simpler streamlined proofs.

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Works this paper leans on

33 extracted references · 32 canonical work pages

  1. [20]

    Katzourakis, Generalised Solutions for Fully Nonlinear PDE Systems and E xistence-Uniqueness The- orems, Journal of Differential Equations, 263 (1), 641–686 (2017)

    N. Katzourakis, Generalised Solutions for Fully Nonlinear PDE Systems and E xistence-Uniqueness The- orems, Journal of Differential Equations, 263 (1), 641–686 (2017)

  2. [9]

    Aronsson, E

    G. Aronsson, E. N. Barron, L∞ variational problems with running costs and constraints , Appl. Math. Optim. 65 no. 1, 53–90 (2012)

  3. [26]

    Katzourakis and T

    N. Katzourakis and T. Pryer, Second Order L∞ Variational Problems and the ∞-Polylaplacian, Advances in Calculus of Variations, 13 (2), 115–140 (2020)

  4. [1]

    Abugirda, N

    H. Abugirda, N. Katzourakis, Existence of 1D Vectorial Absolute Minimisers in L∞ under Minimal Assumptions, Proceedings of the American Mathematical Society, 145, 2567–2575 (2016)

  5. [2]

    Ansini, F

    N. Ansini, F. Prinari, On the lower semicontinuity of supremal functional under di fferential constraints , ESAIM - Control, Opt. and Calc. Var., 21 (4), 1053–1075 (2015)

  6. [3]

    Ayanbayev, N

    B. Ayanbayev, N. Katzourakis, A Pointwise Characterisation of the PDE System of Vectorial Calculus of Variations in L∞, Proceedings of the Royal Society of Edinburgh Section A Mathema tics, 150 (4), 1653–1669 (2017)

  7. [4]

    Aronsson, Minimization problems for the functional supxF (x, f(x), f′(x)), Arkiv f¨ ur Matematik, 6, 33–53 (1965)

    G. Aronsson, Minimization problems for the functional supxF (x, f(x), f′(x)), Arkiv f¨ ur Matematik, 6, 33–53 (1965)

  8. [5]

    Aronsson, Minimization problems for the functional supxF (x, f(x), f′(x))

    G. Aronsson, Minimization problems for the functional supxF (x, f(x), f′(x)). (II) , Arkiv f¨ ur Matematik, 6, 409–431 (1966)

Show all 33 references
  1. [6]

    Aronsson, Extension of functions satisfying Lipschitz conditions , Arkiv f¨ ur Matematik, 6, 551–561 (1967)

    G. Aronsson, Extension of functions satisfying Lipschitz conditions , Arkiv f¨ ur Matematik, 6, 551–561 (1967)

  2. [7]

    Aronsson, On certain singular solutions of the partial differential eq uation u2 xuxx+2uxuyuxy +u2 yuyy = 0, Manuscripta Mathematica, 47, 133–151 (1984)

    G. Aronsson, On certain singular solutions of the partial differential eq uation u2 xuxx+2uxuyuxy +u2 yuyy = 0, Manuscripta Mathematica, 47, 133–151 (1984)

  3. [8]

    Aronsson, Construction of singular solutions to the p-harmonic equation and its limit equation for p = ∞, Manuscripta Mathematica, 56, 135–158 (1986)

    G. Aronsson, Construction of singular solutions to the p-harmonic equation and its limit equation for p = ∞, Manuscripta Mathematica, 56, 135–158 (1986)

  4. [10]

    E. N. Barron, R. Jensen, and C. Wang, The Euler Equation and Absolute Minimizers of L∞ Functionals, Archive for Rational Mechanics and Analysis, 157, 255–283 (2001)

  5. [11]

    E. N. Barron, R. Jensen, and C. Wang, Lower semicontinuity of L∞ functionals, Annales de l’Institut Henri Poincar´ e C, Analyse non lin´ eaire,18 (4), 495–517 (2001)

  6. [12]

    Bhattacharya, E

    T. Bhattacharya, E. DiBenedetto, and J. Manfredi, Limits as p → ∞ of ∇pup = f and related extremal problems, Rend. Sem. Mat. Univ. Politec. Torino, 47, 15–68 (1989). ON SECOND-ORDER L∞ V ARIATIONAL PROBLEMS WITH LOWER-ORDER TERMS 21

  7. [13]

    Clark and N

    E. Clark and N. Katzourakis, Generalized second order vectorial ∞-eigenvalue problems , Proc. R. Soc. Edinb. A Math. 154, 1–21 (2024)

  8. [14]

    Croce, N

    G. Croce, N. Katzourakis, and G. Pisante, D-solutions to the system of vectorial Calculus of Variation s in L∞ via the singular value problem , Discrete and Continuous Dynamical Systems, 37 (12), 6165–6181 (2017)

  9. [15]

    Dacorogna and P

    B. Dacorogna and P. Marcellini, Implicit partial differential equations , Progress in Nonlinear Differential Equations and Applications, Birkh¨ auser (1999)

  10. [16]

    J. M. Danskin, The Theory of Max-Min and its Application to Weapons Allocat ion Problems, Heidelberg Springer Berlin (1967)

  11. [17]

    Fonseca and G

    I. Fonseca and G. Leoni, Modern Methods in the Calculus of Variations: Lp Spaces, Springer Monographs in Mathematics, Springer New York (2007)

  12. [18]

    L. C. Florescu and C. Godet-Thobie, Young Measures and Compactness in Measure Spaces , De Gruyter (2012)

  13. [19]

    Katzourakis, Absolutely Minimising Generalised Solutions to the Equati ons of Vectorial Calculus of Variations in L∞, Calculus of Variations, 56 (15) (2015)

    N. Katzourakis, Absolutely Minimising Generalised Solutions to the Equati ons of Vectorial Calculus of Variations in L∞, Calculus of Variations, 56 (15) (2015)

  14. [21]

    Katzourakis and R

    N. Katzourakis and R. Moser, Existence, Uniqueness and Structure of Second Order Absolu te Minimisers, Archive for Rational Mechanics and Analysis, 231, 1615–1634 (2019)

  15. [22]

    Katzourakis and R

    N. Katzourakis and R. Moser, Variational problems in L∞ involving semilinear second order differential operators, ESAIM Control Optim. Calc. Var. 29, 1–30 (2023)

  16. [23]

    Katzourakis and R

    N. Katzourakis and R. Moser, Minimisers of supremal functionals and mass-minimising 1- currents, Calc. Var. Partial Differential Equations, in press (2024)

  17. [24]

    Katzourakis and R

    N. Katzourakis and R. Moser, Existence, uniqueness and characterisation of local minim isers in higher order calculus of variations in L∞, preprint https://arxiv.org/abs/2403.12625 (2024)

  18. [25]

    Katzourakis and E

    N. Katzourakis and E. Parini, The eigenvalue problem for the ∞-Bilaplacian, Nonlinear Differential Equations Appl. NoDEA 24, 1–25 (2017)

  19. [27]

    Katzourakis and G

    N. Katzourakis and G. Shaw, Counterexamples in calculus of variations in L∞ through the vectorial Eikonal equation , C. R. Math. 356 (5), 498–502 (2018)

  20. [28]

    Kreisbeck, E

    C. Kreisbeck, E. Zappale, Lower semicontinuity and relaxation of nonlocal L∞-functionals, Calculus of Variations and PDE, 59 (138), 1–36 (2020)

  21. [29]

    Q. Miao, C. Wang, Y. Zhou, Uniqueness of Absolute Minimizers for L∞-Functionals Involving Hamilto- nians H(x, p), Archive for Rational Mechanics and Analysis 223 (1), 141–198 (2017)

  22. [30]

    Papamikos, T

    G. Papamikos, T. Pryer, A Lie symmetry analysis and explicit solutions of the two-di mensional ∞- Polylaplacian, Studies in applied mathematics, 142 (1), 48–64 (2019)

  23. [31]

    Prinari, E

    F. Prinari, E. Zappale, A Relaxation Result in the Vectorial Setting and Power Law Ap proximation for Supremal Functionals, J Optim. Theory Appl., 186, 412–452 (2020)

  24. [32]

    Ribeiro, E

    A.N. Ribeiro, E. Zappale, Existence of minimisers for nonlevel convex functionals , SIAM J. Control Opt., 52 (5), 3341–3370 (2014)

  25. [33]

    A. M. Ribeiro and E. Zappale, Revisited convexity notions for L∞ variational problems , Revista Matem´ atica Complutense, published online, https://doi.org/10.1007/s13163-024-00499-0 (2024) B.D., Department of Mathematical Sciences, University of B ath, Bath BA2 7AY, UNITED KI...

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