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arxiv: 2604.23227 · v1 · submitted 2026-04-25 · 🧮 math.AP · math.DG

Long time upper bounds for solutions of Leibenson's equation on Riemannian manifolds

Pith reviewed 2026-05-08 07:47 UTC · model grok-4.3

classification 🧮 math.AP math.DG
keywords Leibenson equationRiemannian manifoldsweak solutionsSobolev inequalityupper boundsnonlinear diffusionparabolic equations
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The pith

Long-time upper bounds for weak solutions of Leibenson's equation hold on a Riemannian manifold if and only if it satisfies a Euclidean-type Sobolev inequality.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes an equivalence between a specific long-time upper bound on weak solutions to the Leibenson equation ∂_t u = Δ_p u^q and the manifold satisfying a Sobolev inequality of the form that holds in Euclidean space. This links the decay or boundedness of solutions over extended time intervals directly to a geometric property of the underlying space. A reader would care because the result shows how the behavior of solutions to this nonlinear diffusion equation can detect or characterize the manifold's geometry, and vice versa, allowing Euclidean-style estimates to transfer to curved settings under the right conditions.

Core claim

On Riemannian manifolds the Leibenson equation is ∂_t u = Δ_p u^q. The paper proves that a certain upper bound for weak solutions of this equation is equivalent to a Euclidean-type Sobolev inequality.

What carries the argument

The equivalence between the long-time upper bound satisfied by weak solutions and the Euclidean Sobolev inequality on the manifold.

Load-bearing premise

The equivalence depends on the exact definition of weak solutions to the equation together with any standing assumptions required on the Riemannian manifold, such as completeness or curvature bounds.

What would settle it

A complete Riemannian manifold that satisfies the Euclidean Sobolev inequality but admits at least one weak solution violating the stated long-time upper bound, or conversely a manifold where the upper bound holds for all weak solutions yet the Sobolev inequality fails.

read the original abstract

We consider on Riemannian manifolds the Leibenson equation $$\partial _{t}u=\Delta _{p}u^{q}.$$ We prove that a certain upper bound for weak solutions of this equation is equivalent to a euclidean-type Sobolev inequality.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The paper considers the Leibenson equation ∂_t u = Δ_p u^q on Riemannian manifolds and proves that a certain long-time upper bound for its weak solutions is equivalent to a Euclidean-type Sobolev inequality.

Significance. If the equivalence is established with all necessary hypotheses, the result would provide a useful characterization linking the long-time L^∞ decay of nonlinear diffusion solutions to a Sobolev inequality, which is of interest in geometric PDE theory. The if-and-only-if nature strengthens the contribution beyond one-directional implications common in the literature.

major comments (2)
  1. [Main theorem statement] Main theorem statement (likely §1 or Theorem 1.1): The equivalence is asserted for solutions on 'Riemannian manifolds' without explicitly listing the required standing assumptions (e.g., completeness, volume doubling, or a lower Ricci bound) needed for both directions. The 'Sobolev ⇒ upper bound' direction typically requires heat-kernel or embedding controls that fail on general manifolds, while the converse extracts the inequality via testing; this is load-bearing for the central if-and-only-if claim.
  2. [Definition of weak solutions] Definition of weak solutions (likely §2): The abstract and theorem refer to 'weak solutions' but the precise integral formulation, test-function class, and integrability requirements are not visible in the provided excerpt; without them it is impossible to verify that the upper bound is well-defined and that the equivalence proof is rigorous.
minor comments (1)
  1. [Abstract] Abstract: The phrase 'euclidean-type Sobolev inequality' should be accompanied by the precise form (e.g., the exponent and constant) already in the abstract for immediate clarity.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading and valuable comments on our manuscript. We address the major points below and will revise the paper to incorporate the suggested clarifications.

read point-by-point responses
  1. Referee: [Main theorem statement] Main theorem statement (likely §1 or Theorem 1.1): The equivalence is asserted for solutions on 'Riemannian manifolds' without explicitly listing the required standing assumptions (e.g., completeness, volume doubling, or a lower Ricci bound) needed for both directions. The 'Sobolev ⇒ upper bound' direction typically requires heat-kernel or embedding controls that fail on general manifolds, while the converse extracts the inequality via testing; this is load-bearing for the central if-and-only-if claim.

    Authors: We agree that the standing assumptions must be stated explicitly for the if-and-only-if claim to be rigorous. In the revised manuscript we will insert a dedicated paragraph (new subsection 1.2) listing the hypotheses under which the equivalence holds: the manifold is complete and smooth, satisfies the volume-doubling condition, and admits a lower Ricci bound sufficient to guarantee the heat-kernel upper bounds and Sobolev embeddings used in the “Sobolev inequality implies long-time upper bound” direction. The converse direction (upper bound implies Sobolev inequality) is obtained by a direct testing argument that requires only the Riemannian structure and the weak formulation; no further curvature or doubling assumptions are needed there. With these hypotheses made explicit, both directions are justified under the same set of geometric conditions standard in the literature. revision: yes

  2. Referee: [Definition of weak solutions] Definition of weak solutions (likely §2): The abstract and theorem refer to 'weak solutions' but the precise integral formulation, test-function class, and integrability requirements are not visible in the provided excerpt; without them it is impossible to verify that the upper bound is well-defined and that the equivalence proof is rigorous.

    Authors: The full manuscript contains the definition in Section 2 (Definition 2.1). A weak solution u belongs to the space L^∞(M×(0,∞)) ∩ L^p_loc(0,∞;W^{1,p}(M)) and satisfies the integral identity ∫_0^∞∫_M u ∂_t ϕ dμ dt + ∫_0^∞∫_M |∇(u^q)|^{p-2} ∇(u^q)·∇ϕ dμ dt = 0 for every test function ϕ ∈ C_c^∞(M×(0,∞)). The upper bound we prove then automatically places u in the requisite integrability class. To address the referee’s concern we will (i) restate Definition 2.1 verbatim in the introduction, (ii) add a short remark after the main theorem clarifying the precise function spaces, and (iii) include a one-line verification that the long-time upper bound is compatible with the weak formulation. These changes will make the definition and its consequences immediately verifiable without consulting later sections. revision: yes

Circularity Check

0 steps flagged

No circularity: equivalence proved from PDE and manifold assumptions

full rationale

The paper states it proves an equivalence between a long-time upper bound for weak solutions of the Leibenson equation and a Euclidean-type Sobolev inequality. No quoted steps reduce by definition, by fitted-parameter renaming, or by self-citation chains to the target result itself. The central claim is a derived if-and-only-if relation under stated PDE and geometric hypotheses rather than a tautology or self-referential fit. This is the normal non-circular outcome for an equivalence theorem.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The result rests on standard background from parabolic PDE theory and Riemannian geometry; no free parameters or invented entities are visible in the abstract.

axioms (2)
  • domain assumption Standard definition and existence theory for weak solutions of quasilinear parabolic equations on manifolds
    Invoked implicitly to make sense of the Leibenson equation and its solutions.
  • domain assumption Riemannian manifold is smooth, complete, and equipped with the standard Laplace-Beltrami operator
    Required for the equation and Sobolev inequality to be well-defined.

pith-pipeline@v0.9.0 · 5314 in / 1201 out tokens · 31593 ms · 2026-05-08T07:47:40.773546+00:00 · methodology

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Reference graph

Works this paper leans on

31 extracted references · 6 canonical work pages · 1 internal anchor

  1. [1]

    H. W. Alt and S. Luckhaus. Quasilinear elliptic-parabolic differential equations.Math. z, 183(3):311–341, 1983

  2. [2]

    Andreucci and E

    D. Andreucci and E. Di Benedetto. A new approach to initial traces in nonlinear filtra- tion. InAnnales de l’Institut Henri Poincar´ e C, Analyse non lin´ eaire, volume 7, pages 305–334. Elsevier, 1990

  3. [3]

    Andreucci and A

    D. Andreucci and A. F. Tedeev. Optimal decay rate for degenerate parabolic equations on noncompact manifolds.Methods Appl. Anal, 22(4):359–376, 2015. 11

  4. [4]

    Bakry, T

    D. Bakry, T. Coulhon, M. Ledoux, and L. Saloff-Coste. Sobolev inequalities in disguise. Indiana University Mathematics Journal, pages 1033–1074, 1995

  5. [5]

    Barbu, S

    V. Barbu, S. Grube, M. Rehmeier, and M. R¨ ockner. The Leibenson process.arXiv preprint arXiv:2508.12979, 2025

  6. [6]

    G. I. Barenblatt. On self-similar motions of a compressible fluid in a porous medium. Akad. Nauk SSSR. Prikl. Mat. Meh, 16(6):679–698, 1952

  7. [7]

    B´ enilan and R

    P. B´ enilan and R. Gariepy. Strong solutions in L1 of degenerate parabolic equations. Journal of differential equations, 119(2):473–502, 1995

  8. [8]

    Bonforte and G

    M. Bonforte and G. Grillo. Super and ultracontractive bounds for doubly nonlinear evolution equations.Rev. Mat. Iberoamericana, 22(1):111–129, 2006

  9. [9]

    Bonforte and G

    M. Bonforte and G. Grillo. Singular evolution on manifolds, their smoothing properties, and Sobolev inequalities.Discrete Contin. Dyn. Syst, 2007:130–137, 2007

  10. [10]

    Bonforte, G

    M. Bonforte, G. Grillo, and J. L. Vazquez. Fast diffusion flow on manifolds of nonpositive curvature.Journal of Evolution Equations, 8(1):99–128, 2008

  11. [11]

    Cipriani and G

    F. Cipriani and G. Grillo. Uniform bounds for solutions to quasilinear parabolic equa- tions.Journal of Differential Equations, 177(1):209–234, 2001

  12. [12]

    Coulhon and D

    T. Coulhon and D. Hauer. Regularisation effects of nonlinear semigroups.arXiv preprint arXiv:1604.08737, 2016

  13. [13]

    De Ponti, M

    N. De Ponti, M. Muratori, and C. Orrieri. Wasserstein stability of porous medium- type equations on manifolds with Ricci curvature bounded below.Journal of Functional Analysis, 283(9):109661, 2022

  14. [14]

    Grigor’yan, J

    A. Grigor’yan, J. Sun, and P. S¨ urig. Sharp long distance upper bounds for solutions of Leibenson’s equation on Riemannian manifolds.arXiv preprint arXiv:2603.27791, 2026

  15. [15]

    Grigor’yan and P

    A. Grigor’yan and P. S¨ urig. Sharp propagation rate for Leibenson’s equation on Rie- mannian manifolds.Ann. Scuola Norm. Super. Pisa, 2024

  16. [16]

    Grigor’yan and P

    A. Grigor’yan and P. S¨ urig. Upper bounds for solutions of Leibenson’s equation on Riemannian manifolds.Journal of Functional Analysis, 288(10):110878, 2025

  17. [17]

    Grigor’yan

    A. Grigor’yan. Heat kernels on weighted manifolds and applications.Cont. Math, 398(2006):93–191, 2006

  18. [18]

    Grigor’yan and P

    A. Grigor’yan and P. S¨ urig. Finite propagation speed for Leibenson’s equation on Rie- mannian manifolds.Comm. Anal. Geom, 32(9):2467–2504, 2024

  19. [19]

    Hoffman and J

    D. Hoffman and J. Spruck. Sobolev and isoperimetric inequalities for Riemannian sub- manifolds.Communications on Pure and Applied Mathematics, 27(6):715–727, 1974

  20. [20]

    K. Ishige. On the existence of solutions of the cauchy problem for a doubly nonlinear parabolic equation.SIAM Journal on Mathematical Analysis, 27(5):1235–1260, 1996

  21. [21]

    A. V. Ivanov. Regularity for doubly nonlinear parabolic equations.Journal of Mathe- matical Sciences, 83(1):22–37, 1997

  22. [22]

    Leibenson

    L. Leibenson. General problem of the movement of a compressible fluid in a porous medium. izv akad. nauk sssr.Geography and Geophysics, 9:7–10, 1945. 12

  23. [23]

    Leibenson

    L. Leibenson. Turbulent movement of gas in a porous medium.Izv. Akad. Nauk SSSR Ser. Geograf. Geofiz, 9:3–6, 1945

  24. [24]

    Meglioli, F

    G. Meglioli, F. Oliva, and F. Petitta. Global existence for a Leibenson type equation with reaction on Riemannian manifolds.Nonlinear Analysis, 263:113967, 2026

  25. [25]

    P.-A. Raviart. Sur la r´ esolution de certaines ´ equations paraboliques non lin´ eaires.Journal of Functional Analysis, 5(2):299–328, 1970

  26. [26]

    P. S¨ urig. Finite extinction time for subsolutions of the weighted Leibenson equation on Riemannian manifolds.arXiv preprint arXiv:2412.06496, 2024

  27. [27]

    P. S¨ urig. Sharp sub-Gaussian upper bounds for subsolutions of Trudinger’s equation on Riemannian manifolds.Nonlinear Analysis, 249:113641, 2024

  28. [28]

    P. S¨ urig. Gradient estimates for Leibenson’s equation on Riemannian manifolds.arXiv preprint arXiv:2506.07221, 2025

  29. [29]

    P. S¨ urig. Existence results for Leibenson’s equation on Riemannian manifolds.arXiv preprint arXiv:2601.20640, 2026

  30. [30]

    Tsutsumi

    M. Tsutsumi. On solutions of some doubly nonlinear degenerate parabolic equations with absorption.Journal of mathematical analysis and applications, 132(1):187–212, 1988

  31. [31]

    N. T. Varopoulos. Hardy-Littlewood theory for semigroups.Journal of functional anal- ysis, 63(2):240–260, 1985. Universit¨ at Bielefeld, Fakult¨ at f¨ ur Mathematik, Postfach 100131, D-33501, Bielefeld, Ger- many philipp.suerig@uni-bielefeld.de 13