Big Ramsey degrees and the two-branching pseudotree

This paper establishes that finite chains within the two-branching countable ultrahomogeneous pseudotree possess finite big Ramsey degrees, specifically determining the degree for chains of length two to be seven, thereby presenting the first example of a countable ultrahomogeneous structure in a finite language where some finite substructures have finite big Ramsey degrees while others have infinite ones.

David Chodounský, Natasha Dobrinen, Thilo Weinert2026-03-10🔢 math

Construction and classification of differential symmetry breaking operators for principal series representations of the pair (SO0(4,1),SO0(3,1))(SO_0(4,1), SO_0(3,1)) for special parameters

This paper constructs and provides a complete classification of all differential symmetry breaking operators between specific vector and line bundles over the 3-sphere and 2-sphere, respectively, in the special case where the rank parameter NN equals the absolute value of the integer mm.

Víctor Pérez-Valdés2026-03-10🔢 math

An Operator Splitting Method for Large-Scale CVaR-Constrained Quadratic Programs

This paper introduces CVQP, an open-source operator splitting method that efficiently solves large-scale quadratic programs with Conditional Value-at-Risk (CVaR) constraints by combining a specialized O(mlogm)O(m\log m) projection algorithm with parallel computations, achieving performance orders of magnitude faster than general-purpose solvers for problems involving millions of scenarios.

Eric Luxenberg, David Pérez-Piñeiro, Steven Diamond, Stephen Boyd2026-03-10🔢 math

Bracket ideals and Hilbert polynomial of filiform Lie algebras

This paper investigates the bifiltration of bracket ideals and the associated bivariate Hilbert polynomial for complex finite-dimensional filiform Lie algebras, demonstrating that this polynomial serves as a refined invariant capable of distinguishing isomorphism classes that remain indistinguishable by traditional numerical invariants related to centralizers and abelian ideal dimensions.

F. J. Castro-Jiménez, M. Ceballos2026-03-10🔢 math