Counting surface subgroups in cusped hyperbolic 3-manifolds

This paper establishes that the number of quasi-Fuchsian surface subgroups in finite-volume noncompact hyperbolic 3-manifolds grows asymptotically as (cg)2g(cg)^{2g}, a result that implies a similar lower bound for purely pseudo-Anosov surface subgroups in mapping class groups, while also demonstrating the existence of infinitely many conjugacy classes of surface subgroups with accidental parabolics.

Xiaolong Hans Han, Zhenghao Rao, Jia Wan2026-03-06🔢 math

Lp\mathrm{L}^p-based Sobolev theory on closed manifolds of minimal regularity: Vector-valued problems

This paper establishes the well-posedness and Lp\mathrm{L}^p-based Sobolev regularity for vector-valued fluid dynamics PDEs, including Stokes and Navier–Stokes equations, on closed manifolds of minimal regularity by developing a parametrization-free variational approach that decouples velocity and pressure variables.

Gonzalo A. Benavides, Ricardo H. Nochetto, Mansur Shakipov2026-03-06🔢 math

Differential symmetry breaking operators from a line bundle to a vector bundle over real projective spaces

This paper classifies and constructs differential symmetry breaking operators from a line bundle over RPn\mathbb{R}\mathbb{P}^n to a vector bundle over RPn1\mathbb{R}\mathbb{P}^{n-1}, while determining their factorization identities, the associated branching laws for generalized Verma modules of sl(n+1,C)\mathfrak{sl}(n+1,\mathbb{C}), and the resulting SL(n,R)SL(n,\mathbb{R})-representations.

Toshihisa Kubo2026-03-06🔢 math

Curvature-dimension condition, rigidity theorems and entropy differential inequalities on Riemannian manifolds

This paper employs an information-theoretic approach to establish the equivalence between the CD(K,m){\rm CD}(K, m) curvature-dimension condition and entropy differential inequalities on Riemannian manifolds, while deriving new rigidity theorems for KK-Einstein and (K,m)(K, m)-Einstein manifolds through the monotonicity of WW-entropy along Wasserstein geodesics.

Xiang-Dong Li2026-03-06🔢 math

The Extra Vanishing Structure and Nonlinear Stability of Multi-Dimensional Rarefaction Waves: The Geometric Weighted Energy Estimates

This paper establishes the nonlinear stability of multi-dimensional rarefaction waves for the compressible Euler equations by introducing a novel Geometric Weighted Energy Method that overcomes derivative loss issues through the identification of a hidden vanishing structure in the top-order derivatives of the characteristic speed.

Haoran He, Qichen He2026-03-06🔬 physics

Topological and rigidity results for four-dimensional hypersurfaces in space forms

This paper establishes topological and rigidity results for four-dimensional hypersurfaces in five-dimensional space forms by characterizing isoparametric hypersurfaces via the Weyl tensor, deriving sharp bounds on the Weyl functional, estimating the second fundamental form in terms of the Euler characteristic, and proving rigidity through integral inequalities, with extensions to locally conformally flat ambient spaces.

Davide Dameno, Aaron J. Tyrrell2026-03-05🔢 math