Pith. sign in

REVIEW 1 major objections 4 minor 50 references

Numerical analysis for constrained and unconstrained Q-tensor energies for liquid crystals

T0 review · 1 major / 4 minor · reviewed 2026-08-07 · deepseek-v4-flash

Pith's one-line read This paper proves that, on sufficiently fine conforming piecewise-linear meshes, the discrete Q-tensor problem has a unique solution near any regular H^2 solution, with optimal O(h) error in the H^1 norm, for both smooth Landau-de Gennes…

desk verdict First a priori error estimates for the Ball-Majumdar Q-tensor potential, mostly sound, but the singular case has a patchable gap in the Kantorovich ball argument. read the letter →

arxiv 2506.04880 v1 pith:SYWWYOWM submitted 2025-06-05 math.NA cs.NA

classification math.NAcs.NA MSC 65N3065N1535Q5676A15
keywords Q-tensorLandau-deGennesBall-MajumdarpotentialfiniteelementmethodapriorierroranalysisNewton-Kantorovichtheoremliquidcrystalssingular
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 establishes a unified a priori error analysis for conforming finite element approximations of equilibrium Q-tensor configurations in nematic liquid crystals. It shows that, given a regular $H^{2}$ solution of the Euler-Lagrange equations with non-homogeneous Dirichlet anchoring, a piecewise linear finite element discretization admits a locally unique discrete solution once the mesh is fine enough, and that the $H^{1}$ error is of optimal order O(h). This is proved both for the standard quartic Landau-de Gennes bulk potential and for the singular Ball-Majumdar potential that enforces the physical bounds on Q-tensor eigenvalues; in the singular case the argument also requires the eigenvalues of the exact solution and its interpolant to stay strictly inside the physical interval. The result matters because singular-potential models prevent unphysical predictions near the isotropic-nematic transition, yet their numerical analysis had been open; this paper supplies the missing optimal-order guarantee for three dimensions with anisotropic elasticity.

What carries the argument

The central object is the Q-tensor, a symmetric traceless 3-by-3 matrix order parameter whose eigenvalues must lie in (-1/3, 2/3) for physically realistic states. The argument runs on three interlocking pieces: the linearized operator around a regular solution is an isomorphism of $H^{1}$_0(Ω) onto its dual (the continuous inf-sup condition); the conforming piecewise linear interpolant I_h Q preserves the physical eigenvalue regime once the mesh is below a threshold, via Weyl's eigenvalue perturbation inequality; and the Newton-Kantorovich theorem converts these ingredients into existence, local uniqueness, and an error bound controlled by the interpolation error. The discrete inf-sup stability of the linearized operator (Theorem 3.2) is established by comparing with the continuous inf-sup constant and controlling the interpolation remainder.

What would settle it

Compute the discrete inf-sup constant for the linearized Ball-Majumdar operator around a regular solution with a fixed positive eigenvalue gap on refinements finer than the claimed threshold; if that constant ever drops below the positivity bound required by Theorem 3.2, the existence and uniqueness conclusion fails. Alternatively, exhibit an anisotropic Ball-Majumdar minimizer whose smallest eigenvalue reaches -1/3 at some point, which directly contradicts the strict-physicality premise.

Watch

Extended reading notes

Core claim

The central claim is Theorem 5.1: for a regular $H^{2}$ solution Q of the Euler-Lagrange equations (2.10) with non-homogeneous Dirichlet data, under the ellipticity conditions (2.8) on the elastic constants, there is a mesh-size threshold such that every shape-regular conforming piecewise linear triangulation finer than it admits a unique discrete solution Q_h near Q, with ||Q - Q_h||_{$H^{1}$(Ω)} ≤ C ||Q - I_h Q||_{$H^{1}$(Ω)} = O(h). The same statement holds for the smooth Landau-de Gennes bulk potential and for the singular Ball-Majumdar potential, provided in the latter case that Q and its interpolant stay strictly inside the physical eigenvalue interval (-1/3, 2/3). The proof constructs the discrete solution as the zero of a nonlinear map on the discrete space and applies the Newton-Kantorovich theorem, with all constants expressed in terms of the ellipticity parameters, the $H^{2}$ norm of Q, and derivatives of the singular potential over the shrunken physical set.

Load-bearing premise

For the singular-potential case, the proof assumes the exact equilibrium solution stays strictly inside the physical eigenvalue interval, with its eigenvalues bounded away from -1/3 and 2/3, and for anisotropic elastic energies this strict physicality has not yet been proved.

Editorial extensions

If this is right

  • For any regular equilibrium state, piecewise linear conforming finite elements resolve it with an H^1 error that scales optimally as the mesh size h.
  • Newton's method started from the conforming interpolant is guaranteed to converge quadratically, so the discrete solution is computable in practice.
  • The analysis covers anisotropic elastic energies, not only the one-constant isotropic case, whenever the elastic constants satisfy the ellipticity condition (2.8).
  • In the singular-potential case, discrete solutions respect the physical eigenvalue constraints as long as the continuous solution is strictly physical, and the error analysis quantifies the extra mesh refinement this requires.
  • Non-homogeneous Dirichlet boundary data, representing surface anchoring, are included through conforming interpolation of the boundary values.

Reading between the lines

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

  • If the strict physicality assumption is later proved for anisotropic elastic energies, the Ball-Majumdar estimates in this paper would transfer verbatim; conversely, a numerical experiment showing eigenvalue violation on arbitrarily fine meshes would indicate the assumption fails.
  • The constants in the singular-potential error bound grow through derivatives of the potential over the shrunken physical set, so one testable consequence is that solutions with a very small eigenvalue gap require correspondingly finer meshes.
  • The same linearization-plus-Newton-Kantorovich template should extend to other order-parameter models with singular energy densities, such as smectic or ferronematic extensions, though the physical-interpolant step would need a new proof per model.
  • A direct computational check of the discrete inf-sup constant on a sequence of refinements would provide a practical certificate of the mesh threshold, testing the theory without resolving the open question of strict physicality.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

1 major / 4 minor

Summary. The manuscript develops a conforming piecewise-linear finite element analysis for the Euler-Lagrange equations of three-dimensional Q-tensor energies for nematic liquid crystals. It treats both the smooth quartic Landau-de Gennes bulk potential and the singular Ball-Majumdar potential, with an anisotropic elastic energy under the ellipticity conditions (2.8). The central result, Theorem 5.1, states that for a regular H^2 solution Q of (2.10) with non-homogeneous Dirichlet data, there is a mesh-size threshold such that for every conforming triangulation finer than it the discrete problem (3.1) has a unique discrete solution Q_h near Q, with ||Q - Q_h||_{H^1(Ω)} <= C ||Q - I_h Q||_{H^1(Ω)} = O(h). The proof combines an interpolation lemma using Weyl's inequality, a discrete inf-sup condition for the linearized problem, and the Newton-Kantorovich theorem. For the Ball-Majumdar potential, the result is conditional on the strict physicality of the exact solution, an assumption that the paper explicitly identifies as an open problem in the anisotropic case.

Significance. If the proof is completed, the paper would provide a unified optimal-order a priori error analysis for both smooth and singular Q-tensor models, including anisotropic elasticity, in a parameter-free setting: there are no fitted constants and no numerical experiments, and the argument is driven by stated assumptions on the exact solution (H^2 regularity, inf-sup nondegeneracy, strict physicality). The paper is also honest about the main assumption for the singular potential. The manuscript's central defect is an omission in the verification of the Kantorovich ball condition for the Ball-Majumdar branch; this is a local and repairable gap, not a fundamental flaw.

major comments (1)
  1. [Remark 2.3; Section 2.2.2(b); Theorem 5.1] The Ball-Majumdar branch of Theorem 5.1 is conditional on the strict physicality of the exact solution, and for anisotropic elastic constants this strict physicality is an open problem, as the paper acknowledges. This limitation should be stated explicitly in the abstract and in the statement of Theorem 5.1, so that readers do not infer an unconditional result for anisotropic elasticity with the singular potential.
minor comments (4)
  1. [Section 5, final paragraph] The local-uniqueness argument after Step 5 is terse and partly circular: it assumes another discrete solution Q_h^* with an O(h) error bound and then concludes that its H^1-distance from I_h Q exceeds r*. Since the Kantorovich theorem already gives uniqueness in the ball \bar{B}(0,r*) \cap D, either delete this paragraph or rewrite it so that the logical role of the additional assumption is clear.
  2. [Lemma 4.4] The Lipschitz constant in Lemma 4.4 is defined as a supremum over Q_phys(epsilon1), and epsilon1 depends on h. The text should note that for h <= h_0 the set Q_phys(epsilon1) is uniformly away from the singular boundary (for instance, after halving h_0 one has epsilon1 >= epsilon/2), so the supremum is finite uniformly in the mesh-size range used in the Kantorovich argument.
  3. [Section 5, Step 4] The inequality r + F1 < 2F1 < 1 uses the fact that r <= F1, which follows from h* <= 1/2 but is not stated. Adding this one-line justification would improve readability.
  4. [Throughout] There are several typographical issues, including 'Frechét' for 'Fréchet' and some inconsistent notation for norms (e.g., ||grad(.)||_{L^2} versus the H^1 seminorm). A careful proofreading pass is recommended.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: Theorem 5.1 is proved from explicit regularity, ellipticity, inf-sup, and physicality hypotheses, with no fitted parameters, no constructed prediction, and no load-bearing self-citation chain.

full rationale

The paper contains no fitted parameters and no numerical experiments; its central claim, Theorem 5.1, is a conditional existence/local-uniqueness/error estimate for conforming finite element approximations of a given regular H^2 solution of the Euler-Lagrange equation (2.10). The proof is carried out from scratch via the Newton-Kantorovich theorem: it verifies Lipschitz continuity of the derivative (Lemmas 4.1 and 4.4), discrete inf-sup stability (Theorem 3.2), residual control (Lemmas 4.3 and 4.6), and then applies Kantorovich to obtain the error bound in terms of the interpolation error of the exact solution. All hypotheses are stated explicitly: the ellipticity condition (2.8), the continuous inf-sup nondegeneracy (2.11), H^2 regularity, and, for the Ball-Majumdar potential, the strict physicality assumption recorded in Remark 2.3. There is no equation or parameter that is fitted to the quantity being predicted, and no step in which the conclusion is identified with an input by definition. Citations to the authors' own earlier work, e.g., [32,34], appear as background or algorithmic context, not as the source of the a priori estimate. The Ball-Majumdar maximum principle is attributed to Ball and Majumdar [3], an external result. The only concern found is an internal proof omission in Step 4 of Theorem 5.1 for the BM branch: the ball-containment condition is argued via an H^1 bound alone, which does not by itself enforce the pointwise eigenvalue separation required by the domain D. This is a repairable gap in the written proof, not a circular reduction, and it does not raise the circularity score.

Assumptions & free parameters 0 free parameters · 5 assumptions · 0 invented entities

The paper's theorems depend on the explicitly stated regularity and physicality assumptions above, on the ellipticity window for the elastic constants, and on classical interpolation and embedding estimates. There are no fitted constants: every constant in the error bounds is a generic, mesh-independent constant. No new particles, forces, or conserved quantities are postulated.

assumptions (5)
  • domain assumption H^2 regularity and continuous inf-sup non-degeneracy (2.11) of the exact solution
    Used throughout; the paper defines a 'regular solution' as one satisfying these assumptions, and they are not derived from the energy minimization.
  • domain assumption Strict physicality of the exact solution for the Ball-Majumdar potential (eigenvalues bounded away from -1/3 and 2/3)
    Remark 2.3 states this is assumed throughout; for anisotropic elastic energy this is open and is the paper's weakest premise. Without it, the singular potential and its derivatives can blow up.
  • domain assumption Ellipticity conditions (2.8) on the elastic constants L1, L2, L3
    Quoted from Lemma 2.1 (citing [26]); required for coercivity and boundedness of the bilinear elastic form A.
  • domain assumption Boundary data Q_b in H^{3/2}(∂Omega; S0), strictly physical in the singular-potential case
    Needed for the weak formulation and for the interpolant of the boundary data to be admissible; stated in Section 2.2.
  • standard math Standard Sobolev embeddings and finite element interpolation estimates in 3D
    Used in Lemmas 3.1, 4.1-4.6 and Theorem 5.1; classical results not proved in the paper.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Numerical analysis for constrained and unconstrained Q-tensor energies for liquid crystals." pith.science (2026). https://pith.science/paper/SYWWYOWM

@misc{pith2026250604880,
  author       = {Pith},
  title        = {Pith review of: Numerical analysis for constrained and unconstrained Q-tensor energies for liquid crystals},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/SYWWYOWM}},
  note         = {Machine review of arXiv:2506.04880}
}
abstract

This paper introduces a comprehensive finite element approximation framework for three-dimensional Landau-de Gennes $Q$-tensor energies for nematic liquid crystals, with a particular focus on the anisotropy of the elastic energy and the Ball-Majumdar singular potential. This potential imposes essential physical constraints on the eigenvalues of the $Q$-tensor, ensuring realistic modeling. We address the approximation of regular solutions to nonlinear elliptic partial differential equations with non-homogeneous boundary conditions associated with Landau-de Gennes energies. The well-posedness of the discrete linearized problem is rigorously demonstrated. The existence and local uniqueness of the discrete solution is derived using the Newton-Kantorovich theorem. Furthermore, we demonstrate an optimal order convergence rate in the energy norm and discuss the impact of eigenvalue constraints on the a priori error analysis.

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

50 extracted references · 50 canonical work pages

  1. [1]

    D. An, W . Wang, and P. Zhang, On equilibrium configurations of nematic liquid crystals droplet with anisotropic elastic energy, Res. Math. Sci. 4 (2017), Paper No. 7, 18

  2. [2]

    J. M. Ball, Liquid crystals and their defects , pp. 1–46, Springer International Publishing, Cham, 2017

  3. [3]

    J. M. Ball and A. Majumdar, Nematic liquid crystals: From Maier-Saupe to a continuum theory, Molecular Crystals and Liquid Crystals 525 (2010), no. 1, 1–11

  4. [4]

    Bauman and D

    P. Bauman and D. Phillips, Regularity and the behavior of eigenvalues for minimizers o f a constrained/u1D444-tensor energy for liquid crystals , Calc. Var. Partial Differential Equations 55 (2016), no. 4, Art. 81, 22

  5. [5]

    Bethuel, H

    F. Bethuel, H. Brezis, and F. Hélein, Asymptotics for the minimization of a Ginzburg-Landau functional, Calc. Var. Partial Differential Equations 1 (1993), no. 2, 123–148

  6. [6]

    Bhatia, Matrix analysis, Graduate Texts in Mathematics, vol

    R. Bhatia, Matrix analysis, Graduate Texts in Mathematics, vol. 169, Springer-Verlag , New Y ork, 1997

  7. [7]

    Bisht, Y

    K. Bisht, Y . Wang, V . Banerjee, and A. Majumdar,Tailored morphologies in two-dimensional ferronematic wells, Phys. Rev. E 101 (2020), 022706

  8. [8]

    H. K. Bisoyi and Q. Li, Liquid crystals: Versatile self-organized smart soft mate rials., Chemical reviews (2021)

Show all 50 references
  1. [9]

    Blanc, D

    C. Blanc, D. Coursault, and E. Lacaze, Ordering nano- and microparticles assemblies with liquid crystals, Liquid Crystals Reviews 1 (2013), no. 2, 83–109

  2. [10]

    S. C. Brenner and L. R. Scott, The mathematical theory of finite element methods , third ed., Texts in Applied Mathematics, vol. 15, Springer, New Y ork, 2008. REFERENCES 20

  3. [11]

    Caimi, G

    F. Caimi, G. Nava, R. Barboza, N. A. Clark, E. Korblova, D . M. Walba, T. Bellini, and L. Lucchetti, Surface alignment of ferroelectric nematic liquid crystal s, Soft Matter 17 (2021), 8130–8139

  4. [12]

    Carstensen, A

    C. Carstensen, A. K. Dond, R. R. Maity, and N. Nataraj, Crouzeix-raviart finite elements for lower energy bounds in ginzburg-landau-type minimisation , Preprint (2024)

  5. [13]

    P. G. Ciarlet, The finite element method for elliptic problems, Classics in Applied Mathematics, vol. 40, Society for Industrial and Applied Mathematics (SI AM), Philadelphia, PA, 2002

  6. [14]

    T. A. Davis and E. C. Gartland, Jr., Finite element analysis of the Landau-de Gennes mini- mization problem for liquid crystals, SIAM J. Numer. Anal. 35 (1998), no. 1, 336–362

  7. [15]

    P. G. de Gennes and J. Prost, The physics of liquid crystals , International Series of Monogr, Clarendon Press, 1993

  8. [16]

    Ern and J.-L

    A. Ern and J.-L. Guermond, Theory and practice of finite elements , Applied Mathematical Sciences, vol. 159, Springer-Verlag, New Y ork, 2004

  9. [17]

    L. C. Evans, O. Kneuss, and H. Tran, Partial regularity for minimizers of singular energy functionals, with application to liquid crystal models , Trans. Amer. Math. Soc. 368 (2016), no. 5, 3389–3413

  10. [18]

    Feireisl, G

    E. Feireisl, G. Schimperna, E. Rocca, and A. Zarnescu, Nonisothermal nematic liquid crystal flows with the Ball-Majumdar free energy , Ann. Mat. Pura Appl. (4) 194 (2015), no. 5, 1269–1299

  11. [19]

    Geng and J

    Z. Geng and J. Tong, Regularity of minimizers of a tensor-valued variational obstacle problem in three dimensions, Calc. Var. Partial Differential Equations 59 (2020), no. 2, Paper No. 57, 35

  12. [20]

    Mariano Giaquinta and Luca Martinazzi, An introduction to the regularity theory for elliptic systems, harmonic maps and minimal graphs , Springer Science & Business Media, 2013

  13. [21]

    Golovaty, M

    D. Golovaty, M. Novack, P. Sternberg, and R. Venkatrama n, A model problem for nematic- isotropic transitions with highly disparate elastic const ants, Arch. Ration. Mech. Anal. 236 (2020), no. 3, 1739–1805

  14. [22]

    Golovaty, P

    D. Golovaty, P. Sternberg, and R. Venkatraman, A Ginzburg-Landau-type problem for highly anisotropic nematic liquid crystals, SIAM J. Math. Anal. 51 (2019), no. 1, 276–320

  15. [23]

    Y . Han, J. Harris, A. Majumdar, and L. Zhang, Elastic anisotropy in the reduced Landau–de Gennes model, Proc. A. 478 (2022), no. 2261, Paper No. 20210966, 22

  16. [24]

    G. R. Luckhurst J. Katriel, G. F. Kventsel and T. J. Sluck in, Free energies in the landau and molecular field approaches , Liquid Crystals 1 (1986), no. 4, 337–355

  17. [25]

    L. V . Kantorovič, Functional analysis and applied mathematics , Vestnik Leningrad. Univ. 3 (1948), no. 6, 3–18

  18. [26]

    Monselesan L

    D. Monselesan L. Longa and H.-R. Trebin, An extension of the Landau-Ginzburg-de Gennes theory for liquid crystals, Liquid Crystals 2 (1987), no. 6, 769–796

  19. [27]

    J. P. F. Lagerwall and G. Scalia, A new era for liquid crystal research: Applications of liqui d crystals in soft matter nano-, bio- and microtechnology , Current Applied Physics 12 (2012), no. 6, 1387–1412. REFERENCES 21

  20. [28]

    V . I. Lebedev and D. N. La˘ ikov, A quadrature formula for a sphere of the 131st algebraic order of accuracy, Dokl. Akad. Nauk 366 (1999), no. 6, 741–745

  21. [29]

    Y . Liu, X. Y . Lu, and X. Xu, Regularity of a gradient flow generated by the anisotropic Landau–de Gennes energy with a singular potential , SIAM J. Math. Anal. 53 (2021), no. 3, 3338–3365

  22. [30]

    X. Lu, X. Xu, and W . Zhang, Blowup rate estimates of a singular potential and its gradie nt in the Landau–de Gennes theory , J. Nonlinear Sci. 32 (2022), no. 1, Paper No. 6, 30

  23. [31]

    Maier and A

    W . Maier and A. Saupe, A simple molecular statistical theory of the nematic crystalline-liquid phase, Z. Naturf. 14a (1959), 882–889

  24. [32]

    R. R. Maity, A. Majumdar, and N. Nataraj, Discontinuous Galerkin finite element methods for the Landau-de Gennes minimization problem of liquid cry stals, IMA J. Numer. Anal. 41 (2021), no. 2, 1130–1163

  25. [33]

    , Parameter dependent finite element analysis for ferronemat ics solutions , Comput. Math. Appl. 103 (2021), 127–155

  26. [34]

    ,/u1D434/u1D45D/u1D45F/u1D456/u1D45C/u1D45F/u1D456and/u1D44E/u1D45D/u1D45C/u1D460/u1D461/u1D452/u1D45F/u1D456/u1D45C/u1D45F/u1D456error analysis for semilinear problems in liquid crystals, ESAIM Math. Model. Numer. Anal. 57 (2023), no. 6, 3201–3250

  27. [35]

    Majumdar, Equilibrium order parameters of nematic liquid crystals in the Landau-de Gennes theory, European J

    A. Majumdar, Equilibrium order parameters of nematic liquid crystals in the Landau-de Gennes theory, European J. Appl. Math. 21 (2010), no. 2, 181–203

  28. [36]

    Majumdar and A

    A. Majumdar and A. Zarnescu, Landau-De Gennes theory of nematic liquid crystals: the Oseen-Frank limit and beyond, Arch. Ration. Mech. Anal. 196 (2010), no. 1, 227–280

  29. [37]

    Myers, C

    L. Myers, C. Swift, J. Rønning, L. Angheluta, and J. Viña ls, A computational study of nematic core structure and disclination interactions in elastical ly anisotropic nematics , Soft Matter 20 (2024), 2900–2914

  30. [38]

    Nesterkina, I

    M. Nesterkina, I. Kravchenko, A. K. H. Hirsch, and C.-M. Lehr, Thermotropic liquid crystals in drug delivery: A versatile carrier for controlled releas e, European Journal of Pharmaceu- tics and Biopharmaceutics 200 (2024), 114343

  31. [39]

    Pacard and T

    F. Pacard and T. Rivière, Linear and nonlinear aspects of vortices , Progress in Nonlinear Differential Equations and their Applications, vol. 39, Bir khäuser Boston, Inc., Boston, MA, 2000, The Ginzburg-Landau model

  32. [40]

    C. D. Schimming and J. Viñals, Anisotropic disclination cores in nematic liquid crystals modeled by a self-consistent molecular field theory , Phys. Rev. E 102 (2020), 010701

  33. [41]

    , Computational molecular field theory for nematic liquid cry stals, Phys. Rev. E 101 (2020), 032702

  34. [42]

    C. D. Schimming, J. Viñals, and S. W . Walker, Numerical method for the equilibrium con- figurations of a Maier-Saupe bulk potential in a Q-tensor mod el of an anisotropic nematic liquid crystal, J. Comput. Phys. 441 (2021), Paper No. 110441, 21

  35. [43]

    C. D. Schimming and J. Viñals, Equilibrium morphology of tactoids in elastically anisotropic nematics, Soft Matter 18 (2022), 8024–8033. REFERENCES 22

  36. [44]

    Schwartz, Y

    M. Schwartz, Y . Geng, H. Agha, R. Kizhakidathazhath, D. Liu, G. Lenzini, and J. P. F. Lagerwall, Linking physical objects to their digital twins via fiducial markers designed for invisibility to humans, Multifunctional Materials 4 (2021), no. 2, 022002

  37. [45]

    B. Shi, Y . Han, A. Majumdar, and L. Zhang, Multistability for nematic liquid crystals in cuboids with degenerate planar boundary conditions, SIAM J. Appl. Math. 84 (2024), no. 2, 756–781

  38. [46]

    Tsakonas, A

    C. Tsakonas, A. J. Davidson, C. V . Brown, and N. J. Mottra m, Multistable alignment states in nematic liquid crystal filled wells , Applied Physics Letters 90 (2007), Article 111913

  39. [47]

    W . Wang, L. Zhang, and P. Zhang,Modelling and computation of liquid crystals, Acta Numer. 30 (2021), 765–851

  40. [48]

    Wilkinson, Strictly physical global weak solutions of a Navier-Stokes /u1D444-tensor system with singular potential, Arch

    M. Wilkinson, Strictly physical global weak solutions of a Navier-Stokes /u1D444-tensor system with singular potential, Arch. Ration. Mech. Anal. 218 (2015), no. 1, 487–526

  41. [49]

    Xia and P

    J. Xia and P. E. Farrell, Variational and numerical analysis of a q-tensor model for smectic-A liquid crystals, ESAIM Math. Model. Numer. Anal. 57 (2023), no. 2, 693–716

  42. [50]

    Zeidler, Nonlinear functional analysis and its applications

    E. Zeidler, Nonlinear functional analysis and its applications. I , Springer-Verlag, New Y ork, 1986, Fixed-point theorems, Translated from the German by P eter R. Wadsack

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.