Entropies, cross-entropies and Rényi divergence: sharp three-term inequalities for probability density functions

This paper establishes a new sharp three-term inequality linking differential Rényi entropy, Rényi divergence, and Rényi cross-entropy for probability density functions, demonstrating that equality holds when one density is an escort of the other and using this result to derive further sharp bounds involving various informational functionals like absolute moments and Fisher information.

Razvan Gabriel Iagar, David Puertas-Centeno2026-03-10🔢 math

Aero-Promptness: Drag-Aware Aerodynamic Manipulability for Propeller-driven Vehicles

This paper introduces Drag-Aware Aerodynamic Manipulability (DAAM), a geometric framework for control allocation in redundant multirotors that utilizes a Riemannian metric to explicitly account for motor torque limits and aerodynamic drag, thereby generating a state-dependent manipulability volume that serves as a natural barrier function to optimize redundancy resolution while characterizing the resulting smooth manifolds and global jump discontinuities.

Antonio Franchi2026-03-10🔢 math

Primitive recursive categoricity spectra

This paper investigates the primitive recursive analogue of computable categoricity spectra, demonstrating that these notions coincide for several natural classes of structures, including relatively Δ20\Delta_{2}^{0}-categorical equivalence structures and linear orders, relatively Δ30\Delta_{3}^{0}-categorical Boolean algebras, and computably categorical trees as partial orders.

Nikolay Bazhenov, Heer Tern Koh, Keng Meng Ng2026-03-10🔢 math

Primitive recursive categoricity spectra of functional structures

This paper investigates the relationship between degrees of categoricity and their punctual (primitive recursive) analogues for functional structures, demonstrating that these notions coincide for non-Δ10\Delta_{1}^{0}-categorical injection structures but diverge for certain Δ10\Delta_{1}^{0}-categorical ones, while also establishing the existence of specific PR-degrees with distinct properties in every non-zero c.e. Turing degree.

Nikolay Bazhenov, Heer Tern Koh, Keng Meng Ng2026-03-10🔢 math

On Representing Matroids via Modular Independence

This paper introduces a matrix-based notion of matroid representation over local commutative rings using modular independence, establishing conditions under which this system forms a matroid, deriving structural properties for codes over chain rings, and demonstrating that certain non-field-representable matroids, such as the Vámos matroid, can be represented over rings like Z/8Z\mathbb{Z}/8\mathbb{Z}.

Koji Imamura, Keisuke Shiromoto2026-03-10🔢 math

Introduction to non-Abelian Patchworking

This paper introduces the framework of non-Abelian patchworking, a geometric method for constructing real algebraic surfaces in RP3\mathbb{R}P^3 via the real locus of non-Abelian complex-phase tropical hypersurfaces, which successfully reproduces all isotopy types of surfaces up to degree three and reveals that primitive PGL2PGL_2 surfaces can exhibit Euler characteristics distinct from their complex counterparts.

Turgay Akyar, Mikhail Shkolnikov2026-03-10🔢 math