Pith. sign in

REVIEW 3 major objections 5 minor 54 references

First eigenvalue estimates on complete balanced Hermitian manifolds

T0 review · 3 major / 5 minor · reviewed 2026-08-04 · deepseek-v4-flash

Pith's one-line read On complete balanced Hermitian manifolds, a positive lower bound on Strominger–Bismut holomorphic Ricci curvature forces the first Laplace eigenvalue to satisfy λ₁ ≥ 2nK, with equality forcing CP¹ rigidity in the Kähler case.

desk verdict Conditions on SB curvature yield genuine new eigenvalue bounds in the balanced case, but the main theorems lean on unpublished compactness/diameter results and should be vetted carefully. read the letter →

arxiv 2511.01297 v2 pith:P3N3NAH6 submitted 2025-11-03 math.DG math.CVmath.SP

classification math.DGmath.CVmath.SP MSC 53C5558C40
keywords balancedHermitianmanifoldStrominger–BismutconnectionfirsteigenvalueLichnerowicz–ObataestimateLi–YauZhong–YangholomorphicRiccicurvaturesectional
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

This paper carries the classical spectral comparison program—Lichnerowicz–Obata, Li–Yau, Zhong–Yang—from Riemannian and Kähler manifolds into complete balanced Hermitian geometry, where the metric is Hermitian but need not be Kähler. The curvature that plays the role of Ricci curvature is the holomorphic Ricci curvature of the Strominger–Bismut connection, the unique Hermitian connection with totally skew-symmetric torsion. The flagship result: if this curvature is bounded below by (2n−1)K with K>0, then the first positive eigenvalue of the Laplace–de Rham operator satisfies λ₁ ≥ 2nK; equality forces maximal diameter D = π/√K, and in the Kähler case forces the manifold to be CP¹ with the Fubini–Study metric. Under weaker or different curvature bounds the paper proves Li–Yau type exponential lower bounds, a Zhong–Yang type bound λ₁ ≥ π²/D², and a λ₁ ≥ K bound from positive Strominger–Bismut holomorphic sectional curvature. The upshot is that balanced non-Kähler manifolds obey the same spectral-geometric comparison principles as Kähler manifolds, with torsion entering only through the chosen connection.

What carries the argument

The Strominger–Bismut connection SB∇ — the unique Hermitian connection whose torsion is a totally skew-symmetric 3-form — supplies the curvature quantities: holomorphic Ricci curvature Ric^{SB,C}(W,W) and holomorphic sectional curvature HSC^{SB}(X). The argument is carried by two identities. The Bochner formula (Proposition 3.4), Δ̄∂|∂u|² = −Ric^{SB,C}(U,U) + λ₁|∂u|² − |SB∇^{1,0}∂u|² − |SB∇^{0,1}∂u|², converts curvature lower bounds into differential inequalities for the test function Q = |∂u|² + (λ₁/4n)u². The integral identity (Theorem 6.1) expresses λ₁∫|∂u|⁴ in terms of Chern curvature, the holomorphic sectional curvature of SB∇, and torsion terms, leading to the λ₁ ≥ K estimate. Balanced

What would settle it

Compute the first eigenvalue of a concrete complete balanced Hermitian non-Kähler manifold with positive SB holomorphic Ricci curvature; if λ₁ < 2nK, Theorem 1.1 is false. Alternatively, verify or disprove the companion diameter bound D ≤ π/√K on a balanced non-Kähler example—e.g. a nilmanifold or Hopf manifold with the appropriate SB-Ricci positivity—since that bound is the step that takes the complete hypothesis to the compact setting.

Watch

Extended reading notes

Core claim

The paper's central claim is that the Strominger–Bismut connection's holomorphic Ricci curvature controls the first eigenvalue exactly as the Riemannian Ricci curvature does in the classical theorems. Specifically, Theorem 1.1 asserts that on a complete balanced Hermitian manifold of complex dimension n with Ric^{SB,C}(W,W) ≥ (2n−1)K|W|² for K>0, one has λ₁ ≥ 2nK, and if equality holds then the diameter is π/√K; when the metric is additionally Kähler, the equality case is isometric to CP¹ with the Fubini–Study metric up to scaling. The paper also proves Li–Yau type estimates (Theorem 1.5), Zhong–Yang type estimates (Theorem 1.7), and an estimate from holomorphic sectional curvature (Theorem

Load-bearing premise

The load-bearing premise is that the external comparison theorems—which turn positive Strominger–Bismut curvature into compactness and a diameter bound D ≤ π/√K—are valid; the paper assumes them without proof, so all its 'complete manifold' results depend on that unproved input.

Editorial extensions

If this is right

  • On a compact balanced Hermitian manifold, a positive lower bound Ric^{SB,C} ≥ (2n−1)K forces λ₁ ≥ 2nK; equality forces the diameter to be exactly π/√K.
  • If the equality case is Kähler, the manifold is CP¹ with the Fubini–Study metric up to scaling, so the classical Obata rigidity survives in the balanced setting.
  • For compact balanced manifolds of dimension n ≥ 3 with Ric^{SB,C} ≥ −K, the first eigenvalue obeys λ₁ ≥ C₁D^{-2} exp(−C₂√K D) with constants depending only on n.
  • For complete balanced manifolds with Ric^{SB,C} ≥ K > 0, the Zhong–Yang bound λ₁ ≥ π²/D² holds; for compact balanced manifolds with nonnegative SB holomorphic Ricci curvature, the same bound holds.
  • Positive holomorphic sectional curvature HSC^{SB} ≥ K > 0 yields λ₁ ≥ K, and on compact balanced manifolds the condition can be relaxed to hold only along the real direction X = U + Ū determined by a first eigenfunction.

Reading between the lines

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

  • The author leaves implicit that the Bochner formula (3.11) and integral identity (6.1) are connection-level identities; the same proof scheme should extend to other Hermitian connections in the Gauduchon family, with the curvature lower bound replaced accordingly. That would be a direct test of how much of the result is really about balance versus the specific connection.
  • Conjecture 1.3—rigidity of the equality case without the Kähler assumption—is the natural next step; if a balanced non-Kähler example attained λ₁ = 2nK, it would be a new extremal object rather than CP¹.
  • The complete-manifold theorems inherit their compactness and diameter bounds from an external preprint; until that preprint's comparison theorem is available independently, the 'complete' results are conditional. A proof that avoids that input would strengthen the programme considerably.
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

3 major / 5 minor

Summary. The paper establishes lower bounds for the first positive eigenvalue of the Laplace–de Rham operator on complete balanced Hermitian manifolds, using curvature lower bounds for the Strominger–Bismut connection. The main results are: a Lichnerowicz–Obata type estimate λ1 ≥ 2nK under a positive lower bound on the holomorphic Ricci curvature (Theorem 1.1), with an equality characterization in the Kähler case; Li–Yau type estimates (Theorem 1.5, Corollary 1.6); Zhong–Yang type estimates (Theorem 1.7, Corollaries 1.8, 1.9); and an estimate λ1 ≥ K under a lower bound on the holomorphic sectional curvature of the Strominger–Bismut connection (Theorem 1.10). The proofs use Bochner-type identities, maximum principles, and an integral identity for compact balanced manifolds. Several results are stated for complete manifolds but rely on external compactness and diameter assertions from an unpublished preprint.

Significance. If the results are correct, they would constitute a meaningful extension of classical Riemannian and Kähler spectral estimates to balanced non-Kähler manifolds, which is a timely and useful contribution. The paper contains original Bochner-type identities (e.g., Proposition 3.4, Eq. (3.11)) and an integral identity (Theorem 6.1) that are of independent interest. The derivations are explicit and no fitted constants or circular parameter choices appear. However, the significance is currently tempered by the fact that the main theorems depend on compactness and diameter theorems from the unpublished preprint [47], and by a few statement-level inaccuracies that must be corrected.

major comments (3)
  1. [§3 (Theorem 1.1), §4 (Corollary 1.6), §5 (Theorem 1.7), §6 (Theorem 1.10)] The proofs of Theorems 1.1, 1.7, 1.10 and Corollary 1.6 invoke [47, Theorems 1.5, 1.3, 1.4] to conclude compactness and, in the case of Theorem 1.1, the diameter bound D ≤ π/√K. These assertions are load-bearing: the eigenfunction u, the integration by parts in (3.22), and the strong maximum principle all require compactness, and the equality case uses the diameter bound. Since [47] is an unpublished arXiv preprint and the needed statements are not proved in this paper, the main theorems are conditional as written. Please either prove the needed compactness/diameter results, cite a published version, or explicitly state the theorems as conditional on [47].
  2. [Theorem 1.7, Eq. (1.13)] The hypothesis as stated, Ric^{SB,C}(W,W) ≥ K for all W ∈ Γ(M,T^{1,0}M) with K > 0, is not meaningful because the left-hand side is homogeneous of degree 2 in W; taking W → 0 gives 0 ≥ K, a contradiction. The intended condition is presumably Ric^{SB,C}(W,W) ≥ K|W|². The proof in §5 only uses the nonnegativity of Ric^{SB,C}(Y,Y) via Lemma 5.1, which would follow from the homogeneous version, so the fix is local, but the stated theorem must be corrected.
  3. [§5, Eq. (5.7)] The crucial Zhong–Yang type inequality (5.7) is asserted with the phrase 'as in [54]' but is not proved. This inequality is the bridge from Lemma 5.1 to the eigenvalue lower bound λ1 ≥ π²/D², and it is not a trivial transcription: the Bochner formula, the test function ψ, and the normalization all differ from the classical Riemannian setting. Please provide a complete derivation of (5.7), or state and prove the adapted version of [54, Lemmas 3–5] used here.
minor comments (5)
  1. [Abstract vs. §6] The abstract advertises a 'torsion-commutator condition along a first eigendirection' in connection with the holomorphic sectional curvature estimate, but Theorem 1.10 and Corollary 1.11 contain no such condition. Please align the abstract with the actual statements.
  2. [Theorems 1.1, 1.7, 1.10] The quantity λ1 is defined in (1.1) for a compact manifold, but Theorems 1.1, 1.7, and 1.10 are stated for complete manifolds before compactness is established. The statements should read 'then M is compact and λ1 ≥ ...' to avoid an initially undefined symbol.
  3. [Throughout] There are several typos and minor wording issues: 'satiesfy' (p.2), 'pesudo–Hermitian' (p.2), 'the the' (p.5), 'Cauchy-Schwartz' (p.13), 'arcsiny' (p.19). A careful proofreading pass is recommended.
  4. [§3, Proof of Lemma 3.1] In (3.4), the equality (∆_{\bar∂} f,F) = (∆_{\partial} f,F) is obtained by an analogous computation, but the sentence 'Moreover, we obtain that' makes it look like an independent assumption. Please clarify that it follows by repeating the previous argument.
  5. [§3, Equality case of Theorem 1.1] The sentence 'we may assume u²(γ) ≠ 1 other than the points x1 and x2 without loss of generality' is a bit terse. If u reaches ±1 on a nontrivial interval, the geodesic integration argument needs a short justification; please add a sentence or a reference to the standard Obata argument.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: eigenvalue lower bounds are derived from curvature assumptions; compactness is imported from external [47], and the sole self-citation [51] is peripheral.

full rationale

I find no step in which Theorem 1.1, 1.5, 1.7, or 1.10 reduces by construction to its input. The proofs use the curvature assumption in Bochner-type identities (e.g. (3.11), (4.7)) and integral identities (Theorem 6.1) to obtain differential inequalities such as (3.22), then integrate/maximum-principle. Identity (2.25) is imported from published [39], and Theorem 6.1 explicitly extends [40]; neither is a renaming of the target estimate. The complete-to-compact steps in the proofs of Theorems 1.1, 1.7, 1.10 and Corollary 1.6 are genuine external assumptions: the text says "As K>0, [47, Theorem 1.5] ensures that (1.4) implies that M is compact and D≤π/√K" (and similarly [47, Theorems 1.3, 1.4]). Since [47] is not by the present author and is not the result being proved, reliance on it is a correctness risk if the preprint is wrong, but it is not circularity. The only author-overlap citation is [51] in Corollary 1.9, used only to convert a compact Hermitian surface with parallel torsion and nonnegative SB-Ricci into a Kähler surface; this is a peripheral application and does not support the main theorems. No fitted parameters are relabelled as predictions, and no self-citation uniqueness theorem forces the choice. Hence no circular step can be exhibited.

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

No free parameters or invented entities. The paper is pure a priori differential geometry; the central estimates are not fitted. It rests on several imported curvature identities and comparison theorems, including three from a recent preprint [47] and one from the author's own [51].

assumptions (5)
  • standard math [39, Cor 1.8]/Lemma 2.1: explicit curvature relations (2.20)-(2.24) between Strominger–Bismut and Chern curvatures on balanced Hermitian manifolds.
    Imported as a black box; the Bochner formula (3.11) and identity (2.25) rely on it.
  • domain assumption [47, Thm 1.3/1.4/1.5]: positive SB holomorphic Ricci/HSC implies compactness and diameter bounds D ≤ π/√K.
    Used in proofs of Thm 1.1, 1.7, 1.10 to reduce complete to compact and to get the diameter bound. The cited paper is a preprint by X. Yang.
  • standard math [54, Lemmas 3-5]: existence of the Zhong–Yang test function ψ and the integration estimate (5.7)-(5.8).
    The proof of Theorem 1.7 says 'as in [54]' and does not reproduce the computation.
  • standard math [13, Thm 1.3] Cheng's maximal diameter rigidity.
    Used in equality case of Theorem 1.1 to identify the Kähler equality manifold as CP¹.
  • domain assumption [51, Thm 1.5] (by the same author): compact Hermitian surfaces with non-negative Ric^{SB(3)}+Ric^{SB(4)} are Kähler.
    Used only in Corollary 1.9; it is the paper's own prior result and is not re-proved here.

how reviews work

0 comments
Cite this review

Pith. "Pith review of First eigenvalue estimates on complete balanced Hermitian manifolds." pith.science (2026). https://pith.science/paper/P3N3NAH6

@misc{pith2026251101297,
  author       = {Pith},
  title        = {Pith review of: First eigenvalue estimates on complete balanced Hermitian manifolds},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/P3N3NAH6}},
  note         = {Machine review of arXiv:2511.01297}
}
read the original abstract

We establish lower bounds for the first positive eigenvalue of the Laplace--de Rham operator on complete balanced Hermitian manifolds in terms of curvature of the Strominger--Bismut connection. Under a positive lower bound for its holomorphic Ricci curvature, we prove a Lichnerowicz--Obata type estimate and characterize the equality case in the K\"ahler setting. We also derive Li--Yau and Zhong--Yang type estimates from lower bounds on the same holomorphic Ricci curvature, including estimates under weaker assumptions only along a first eigendirection in the compact case. Finally, under a positive lower bound for the holomorphic sectional curvature of the Strominger--Bismut connection and a torsion-commutator condition along a first eigendirection, we obtain a lower bound for the first eigenvalue. In the compact case, the commutator condition follows from vanishing of the Strominger--Bismut torsion in that eigendirection. These results extend several classical K\"ahler and Riemannian spectral estimates to the balanced non-K\"ahler setting.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

54 extracted references · 4 linked inside Pith

  1. [47]

    Yang, Comparison theorems in Hermitian geometry I, arXiv: 2507.15002v1 [math.DG]

    X. Yang, Comparison theorems in Hermitian geometry I, arXiv: 2507.15002v1 [math.DG]

  2. [54]

    Zhong, H

    J. Zhong, H. Yang, On the estimate of the first eigenvalue of a compact Riemannian manifold, Sci. Sin Ser. A 27(12) (1984), 1265–1273. (Liangdi Zhang) Beijing Institute of Mathematical Sciences and Applications, Beijing 101408, P. R. China Email address:ldzhang91@163.com

  3. [1]

    Andrada, R

    A. Andrada, R. Villacampa, Bismut connection on Vaisman manifolds, Math. Z. 302 (2022), 1091–1126

  4. [2]

    Angella, A

    D. Angella, A. Otal, L. Ugarte, R. Villacampa, On Gauduchon connections with K¨ ahler-like curvatures, Comm. Anal. Geom. 30(5) (2022), 961–1006

  5. [3]

    Apostolov, G

    V. Apostolov, G. Barbaro, K. H. Lee, J. Streets, Rigidity results for non-K¨ ahler Calabi-Yau geometries on threefolds, arXiv:2408.09648v4 [math.DG]

  6. [4]

    Bakry, Z

    D. Bakry, Z. Qian, Some new results on eigenvectors via dimension, diameter, and Ricci Curvature, Adv. Math. 155(1) (2000), 98–153

  7. [5]

    Batista, M

    M. Batista, M. P. Cavalcante, J. Pyo, Some isoperimetric inequalities and eigenvalue estimates in weighted manifolds, J. Math. Anal. Appl. 419(1) (2014), 617–626

  8. [6]

    Branding, G

    V. Branding, G. Habib, Eigenvalue estimates on weighted manifolds, Results Math. 79(5) (2024), 187

Show all 54 references
  1. [7]

    J. M. Bismut, A local index theorem for non-K¨ ahler manifolds, Math. Ann. 284(4) (1989), 681–699

  2. [8]

    S. C. Chang, H. L. Chiu, On the estimate of the first eigenvalue of a sublaplacian on a pseudohermitian 3-manifold, Pac. J. Math. 232(2) (2007), 269–282

  3. [9]

    S. C. Chang, H. L. Chiu, On the CR analogue of Obata’s theorem in a pseudohermi- tian 3-manifold, Math. Ann. 345 (2009), 33–51

  4. [10]

    D. Chen, T. Zheng, M. Lu, Eigenvalue estimates on domains in complete noncompact Riemannian manifolds, Pac. J. Math. 255(1) (2012), 41–54

  5. [11]

    Q. M. Cheng, H. Yang, Estimates on eigenvalues of Laplacian, Math. Ann. 331 (2005), 445–460

  6. [12]

    Q. M. Cheng, H. Yang, Estimates for eigenvalues on Riemannian manifolds, J. Differ. Equations 247(8) (2009), 2270–2281

  7. [13]

    S. Y. Cheng, Eigenvalue comparison theorems and its geometric applications, Math. Z. 143(3) (1975), 289–297

  8. [14]

    J. Chu, F. Wang, K. Zhang, The rigidity of eigenvalues on K¨ ahler manifolds with positive Ricci lower bound, J. Reine Angew. Math. 820 (2025), 213–233

  9. [15]

    F. Du, J. Mao, Q. Wang, C. Xia, Estimates for eigenvalues of weighted Laplacian and weightedp-Laplacian, Hiroshima Math. J. 51(3) (2021), 335–353

  10. [16]

    A. Fino, N. Tardini, L. Vezzoni, Pluriclosed and Strominger K¨ ahler-like metrics com- patible with abelian complex structures, Bull. London Math. Soc. 54(5) (2022), 1862– 1872. 28

  11. [17]

    Futaki, K¨ ahler-Einstein metrics and integral invariants, Lecture Notes in Math., 1314 Springer-Verlag, Berlin (1988)

    A. Futaki, K¨ ahler-Einstein metrics and integral invariants, Lecture Notes in Math., 1314 Springer-Verlag, Berlin (1988)

  12. [18]

    Greenleaf, The first eigenvalue of a sub-Laplacian on a pseudo-Hermitian manifold, Commun

    A. Greenleaf, The first eigenvalue of a sub-Laplacian on a pseudo-Hermitian manifold, Commun. Part. Diff. Eq. 10(2) (1985), 191–217

  13. [19]

    Grieser, Uniform bounds for eigenfunctions of the Laplacian on manifolds with boundary, Commun

    D. Grieser, Uniform bounds for eigenfunctions of the Laplacian on manifolds with boundary, Commun. Part. Diff. Eq. 27(7–8) (2002), 1283–1299

  14. [20]

    P. Li, J. Wang, Comparison theorem for K¨ ahler manifolds and positivity of spectrum, J. Differential Geom. 69(1) (2005), 43–74

  15. [21]

    P. Li, S. T. Yau, Eigenvalues of a compact Riemannian manifold, AMS Proc. Symp. Pure Math. 36 (1980) 205–239

  16. [22]

    S. Y. Li, H. S. Luk, The sharp lower bound for the first positive eigenvalue of a sub-Laplacian on a pseudo-Hermitian manifold, P. Am. Math. Soc. 132(3) (2004), 789–798

  17. [23]

    S. Y. Li, M. A. Tran, On the CR-Obata theorem and some extremal problems asso- ciated to pseudoscalar curvature on the real ellipsoids inC n+1, T. Am. Math. Soc. 363(8) (2011), 4027-4042

  18. [24]

    X. D. Li, Liouville theorems for symmetric diffusion operators on complete Riemann- ian manifolds, J. Math. Pures Appl. 84(10) (2005), 1295-1361

  19. [25]

    X. Li, K. Wang, First Robin eigenvalue of thep-Laplacian on Riemannian manifolds, Math. Z. 298 (2021), 1033-1047

  20. [26]

    Lichnerowicz, G´ eom´ etrie des groupes de transformations, Travaux et Recherches Math´ ematiques, III, Dunod, Paris (1958)

    A. Lichnerowicz, G´ eom´ etrie des groupes de transformations, Travaux et Recherches Math´ ematiques, III, Dunod, Paris (1958)

  21. [27]

    Liu, K¨ ahler manifolds with Ricci curvature lower bound, Asian J

    G. Liu, K¨ ahler manifolds with Ricci curvature lower bound, Asian J. Math. 18 (2014), 69–99

  22. [28]

    K. Liu, X. Yang, Geometry of Hermitian manifolds, Internat. J. Math. 23(6) (2012), 1250055

  23. [29]

    K. Liu, X. Yang, Ricci curvatures on Hermitian manifolds, T. Am. Math. Soc. 369(7) (2017), 5157–5196

  24. [30]

    Y. Liu, Y. Yang, Lower bound estimates of the first eigenvalue for boundary of com- pact manifolds, Acta. Math. Sin. English Ser. (2025), https://doi.org/10.1007/s10114- 025-3403-3

  25. [31]

    Mohamed, D

    A. Mohamed, D. Vassilev, The Obata first eigenvalue theorem on a seven-dimensional quaternionic contact manifold, J. Geom. Anal. 33(1) (2023), 13

  26. [32]

    Munteanu, A sharp estimate for the bottom of the spectrum of the Laplacian on K¨ ahler manifolds

    O. Munteanu, A sharp estimate for the bottom of the spectrum of the Laplacian on K¨ ahler manifolds. J. Differential Geom. 83(1) (2009), 163–187

  27. [33]

    Munteanu, On a characterization of the complex hyperbolic space

    O. Munteanu, On a characterization of the complex hyperbolic space. J. Differential Geom. 84(3) (2010), 611–621

  28. [34]

    L. Ni, F. Zheng, On Hermitian manifolds whose Chern connection is Ambrose-Singer, Trans. Amer. Math. Soc. 376(9) (2023), 6681–6707

  29. [35]

    Obata, Certain conditions for a Riemannian manifold to be isometric with a sphere, J

    M. Obata, Certain conditions for a Riemannian manifold to be isometric with a sphere, J. Math. Soc. Japan 14 (1962), 333–340

  30. [36]

    C. D. Sogge, Eigenfunction and Bochner Riesz estimates on manifolds with boundary, Math. Res. Lett. 9 (2002), 205–216

  31. [37]

    Strominger, Superstrings with torsion, Nuclear Phys

    A. Strominger, Superstrings with torsion, Nuclear Phys. B 274(2) (1986), 253-284

  32. [38]

    L. F. Tam, C. Yu, Some comparison theorems for K¨ ahler manifolds, manuscripta math. 137(3-4) (2012), 483–495

  33. [39]

    J. Wang, X. Yang, Curvatures of real connections on Hermitian manifolds, Pac. J. Math. 337(2) (2025), 365–391

  34. [40]

    M. Wang, X. Yang, First eigenvalue estimates on complete K¨ ahler manifolds, arXiv: 2507.09203v1 [math.DG]

  35. [41]

    Q. Wang, B. Yang, F. Zheng, On Bismut flat manifolds, Trans. Amer. Math. Soc. 373 (2020), 5747–5772. 29

  36. [42]

    J. Y. Wu, Upper bounds on the first eigenvalue for a diffusion operator via Bakry– ´Emery Ricci curvature, J. Math. Anal. Appl. 361(1) (2010), 10–18

  37. [43]

    J. Y. Wu, Upper Bounds on the first eigenvalue for a diffusion operator via Bakry– ´Emery Ricci curvature II, Results. Math. 63 (2013), 1079–1094

  38. [44]

    L. Wu, X. Song, M. Zhu, Eigenvalue estimates for Beltrami-Laplacian under Bakry– ´Emery Ricci curvature condition, Potential Anal. 60 (2024), 597–614

  39. [45]

    B. Yang, F. Zheng, On curvature tensors of Hermitian manifolds, Comm. Anal. Geom. 26(5) (2018), 1195–1222

  40. [46]

    B. Yang, F. Zheng, On compact Hermitian manifolds with flat Gauduchon connec- tions, Acta Math. Sin. (Engl. Ser.) 34(8) (2018), 1259–1268

  41. [48]

    Yang, Chern number identities on compact complex surface and applications, arXiv:2508.11171v1 [math.DG]

    X. Yang, Chern number identities on compact complex surface and applications, arXiv:2508.11171v1 [math.DG]

  42. [49]

    S. T. Yau, Q. Zhao, F. Zheng, On Strominger K¨ ahler-like manifolds with degenerate torsion, Trans. Amer. Math. Soc. 376(5) (2023), 3063–3085

  43. [50]

    Ye, Bismut Einstein metrics on compact complex manifolds, J

    Y. Ye, Bismut Einstein metrics on compact complex manifolds, J. Funct. Anal. 288 (2025), 110805

  44. [51]

    Zhang, K¨ ahlerness of compact Hermitian surfaces under semi-definite Strominger– Bismut–Ricci curvatures, arXiv:2510.06648v3 [math.DG]

    L. Zhang, K¨ ahlerness of compact Hermitian surfaces under semi-definite Strominger– Bismut–Ricci curvatures, arXiv:2510.06648v3 [math.DG]

  45. [52]

    Q. Zhao, F. Zheng, Complex nilmanifolds and K¨ ahler-like connections, J. Geom. Anal. 146 (2019), 103512

  46. [53]

    Q. Zhao, F. Zheng, Strominger connection and pluriclosed metrics, J. reine angew. Math. 796 (2023), 245–267

Pith tools

Reviewed August 4, 2026 · model on record in the stance chip above.