Cat. A2

Matrix Uvarov Transformation on the Unit Circle: Asymptotic Properties

Let 𝜎 be an 𝑙×𝑙 Hermitian matrix measure supported on the unit circle. In this contribution, we study some algebraic and analytic properties of matrix orthogonal polynomials associated with the Uvarov matrix transformation of 𝜎 defined by …

Riemann Problem for a 2x2 Hyperbolic System with Linear Damping

In this paper, we study the Riemann problem for a 2x2 nonstrictly hyperbolic system with linear damping. We introduce the special time-dependent viscosity to obtain approximate solutions. Therefore, we solve the Riemann problem (1.1)–(1.2) by …

Comparación de la eficiencia científica entre Colombia y México a través de indicadores relativos de producción y calidad científica

Con indicadores relativos analizamos la dinámica de la producción y calidad científica de Colombia y México en el área de Ciencias Sociales (CS). Entre 2006 a 2017 estimamos la producción científica, la inversión en I+D, la cantidad de doctores …

Semi-linear Cauchy problem and Markov process associated with a $p$-adic non-local ultradiffusion operator

This work is dedicated to study the pseudodifferential operator (𝐷𝛼𝑑1,𝑑2𝜑)(𝑥)=−∫ℚ𝑛𝑝−𝛼𝑑1,𝑑2(𝑦)[𝜑(𝑥+𝑦)−𝜑(𝑥)]𝑑𝑛𝑦, which can be seen as a generalization of Taibleson operator; here 𝛼𝑑1,𝑑2(𝑥)=max{‖𝑥‖𝑑1𝑝, ‖𝑥‖𝑑2𝑝}𝛼. We show that semi-linear Cauchy problem …

Skew Poincaré-Birkhoff-Witt extensions over weak compatible rings

In this paper, we introduce weak (Σ,Δ)-compatible rings and study skew Poincaré–Birkhoff–Witt extensions over these rings. We characterize the weak notion of compatibility for several noncommutative rings appearing in noncommutative algebraic …

Non-radial functions, nonlocal operators and Markov processes over p-adic numbers

The main goal of this article is to study a new class of nonlocal operators and the Cauchy problem for certain parabolic-type pseudodifferential equations naturally associated with them. The fundamental solutions of these equations are transition …

Double Ore extensions versus graded skew PBW extensions

In this article, we present necessary and sufficient conditions for a graded (trimmed) double Ore extension to be a graded (quasi-commutative) skew PBW extension. Using this fact, we prove that a graded skew PBW extension A=σ(R)⟨x1,x2⟩ of an …

A Computational Maple Library for Skew PBW Extensions

In this paper we present a computational package developed for making computations involved in many homological applications of the Gr"obner theory of skew PBW extensions.

Copies of c_0(Γ) in the space of bounded linear operators

The space L(𝑋,𝑌) stands for the Banach space of all bounded linear operators from X to Y endowed with the operator norm. It is shown that 𝑐0(Γ) embeds into (𝑋,𝑌) if and only if 𝑙∞(Γ) embeds into (𝑋,𝑌) or 𝑐0(Γ) embeds into Y. As a consequence, we …

Elementary Matrix-computational Proof of Quillen-Suslin Theorem for Ore Extensions

In this short note we present an elementary matrix-constructive algorithmic proof of the Quillen-Suslin theorem for Ore extensions $A:=K[x;\sigma, \delta]$, where $K$ is a division ring, $\sigma: K \to K$ is a division ring automorphism and $\sigma: …