Absolute continuity for Jacobi matrices with power-like weights

Wojciech Motyka

Displaying similar documents to “Absolute continuity for Jacobi matrices with power-like weights”

Hamilton-Jacobi flows and characterization of solutions of Aronsson equations

Petri Juutinen, Eero Saksman (2007)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

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In this note, we verify the conjecture of Barron, Evans and Jensen [3] regarding the characterization of viscosity solutions of general Aronsson equations in terms of the properties of associated forward and backwards Hamilton-Jacobi flows. A special case of this result is analogous to the characterization of infinity harmonic functions in terms of convexity and concavity of the functions $r \mapsto {max}_{y \in B_{r} (x)} u (y)$ and $r \mapsto {min}_{y \in B_{r} (x)} u (y)$ , respectively.

Nested matrices and inverse $M$ -matrices

Jeffrey L. Stuart (2015)

Czechoslovak Mathematical Journal

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Given a sequence of real or complex numbers, we construct a sequence of nested, symmetric matrices. We determine the $L U$ - and $Q R$ -factorizations, the determinant and the principal minors for such a matrix. When the sequence is real, positive and strictly increasing, the matrices are strictly positive, inverse $M$ -matrices with symmetric, irreducible, tridiagonal inverses.

Complexity of computing interval matrix powers for special classes of matrices

David Hartman, Milan Hladík (2020)

Applications of Mathematics

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Computing powers of interval matrices is a computationally hard problem. Indeed, it is NP-hard even when the exponent is 3 and the matrices only have interval components in one row and one column. Motivated by this result, we consider special types of interval matrices where the interval components occupy specific positions. We show that computing the third power of matrices with only one column occupied by interval components can be solved in cubic time; so the asymptotic time complexity...

Jacobi decomposition of weighted Triebel-Lizorkin and Besov spaces

George Kyriazis, Pencho Petrushev, Yuan Xu (2008)

Studia Mathematica

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The Littlewood-Paley theory is extended to weighted spaces of distributions on [-1,1] with Jacobi weights $w (t) = {(1 - t)}^{α} {(1 + t)}^{β}$ . Almost exponentially localized polynomial elements (needlets) $φ_{ξ}$ , $ψ_{ξ}$ are constructed and, in complete analogy with the classical case on ℝⁿ, it is shown that weighted Triebel-Lizorkin and Besov spaces can be characterized by the size of the needlet coefficients $⟨ f, φ_{ξ} ⟩$ in respective sequence spaces.

Torsion points on curves and common divisors of $a^{k} - 1$ and $b^{k} - 1$

Nir Ailon, Zéev Rudnick (2004)

Acta Arithmetica

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A generalization of Bateman's expansion and finite integrals of Sonine's and Feldheim's type

Giacomo Gigante (2010)

Colloquium Mathematicae

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Let ${A_{k}}_{k = 0}^{+ \infty}$ be a sequence of arbitrary complex numbers, let α,β > -1, let Pₙα,βn=0+∞ $b e t h e J a c o b i p o l y n o m i a l s a n d d e f i n e t h e f u n c t i o n s$ $H ₙ (α, z) = \sum_{m = n}^{+ \infty} (A_{m} z^{m}) / (Γ (α + n + m + 1) (m - n)!)$ , $G (α, β, x, y) = \sum_{r, s = 0}^{+ \infty} (A_{r + s} x^{r} y^{s}) / (Γ (α + r + 1) Γ (β + s + 1) r! s!)$ . Then, for any non-negative integer n, $\int_{0}^{π / 2} G (α, β, x ² s i n ² ϕ, y ² c o s ² ϕ) P ₙ^{α, β} (c o s ² ϕ) s i n^{2 α + 1} ϕ c o s^{2 β + 1} ϕ d = 1 / 2 H ₙ (α + β + 1, x ² + y ²) P ₙ^{α, β} ((y ² - x ²) / (y ² + x ²))$ . When $A_{k} = {(- 1 / 4)}^{k}$ , this formula reduces to Bateman’s expansion for Bessel functions. For particular values of y and n one obtains generalizations of several formulas already known for Bessel functions, like Sonine’s first and second finite integrals and certain Neumann series expansions. Particular choices of ${A_{k}}_{k = 0}^{+ \infty}$ allow one to write all these type of formulas...

Doubly stochastic matrices and the Bruhat order

Richard A. Brualdi, Geir Dahl, Eliseu Fritscher (2016)

Czechoslovak Mathematical Journal

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The Bruhat order is defined in terms of an interchange operation on the set of permutation matrices of order $n$ which corresponds to the transposition of a pair of elements in a permutation. We introduce an extension of this partial order, which we call the stochastic Bruhat order, for the larger class $Ω_{n}$ of doubly stochastic matrices (convex hull of $n \times n$ permutation matrices). An alternative description of this partial order is given. We define a class of special faces of $Ω_{n}$ induced by permutation...

Inverse eigenvalue problem for constructing a kind of acyclic matrices with two eigenpairs

Maryam Babaei Zarch, Seyed Abolfazl Shahzadeh Fazeli, Seyed Mehdi Karbassi (2020)

Applications of Mathematics

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We investigate an inverse eigenvalue problem for constructing a special kind of acyclic matrices. The problem involves the reconstruction of the matrices whose graph is an $m$ -centipede. This is done by using the $(2 m - 1)$ st and $(2 m)$ th eigenpairs of their leading principal submatrices. To solve this problem, the recurrence relations between leading principal submatrices are used.

Circulant matrices with orthogonal rows and off-diagonal entries of absolute value $1$

Daniel Uzcátegui Contreras, Dardo Goyeneche, Ondřej Turek, Zuzana Václavíková (2021)

Communications in Mathematics

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It is known that a real symmetric circulant matrix with diagonal entries $d \geq 0$ , off-diagonal entries $\pm 1$ and orthogonal rows exists only of order $2 d + 2$ (and trivially of order $1$ ) [Turek and Goyeneche 2019]. In this paper we consider a complex Hermitian analogy of those matrices. That is, we study the existence and construction of Hermitian circulant matrices having orthogonal rows, diagonal entries $d \geq 0$ and any complex entries of absolute value $1$ off the diagonal. As a particular case, we consider...

An improvement of an inequality of Fiedler leading to a new conjecture on nonnegative matrices

Assaf Goldberger, Neumann, Michael (2004)

Czechoslovak Mathematical Journal

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Suppose that $A$ is an $n \times n$ nonnegative matrix whose eigenvalues are $λ = ρ (A), λ_{2}, ..., λ_{n}$ . Fiedler and others have shown that $det (λ I - A) \leq λ^{n} - ρ^{n}$ , for all $λ > ρ$ , with equality for any such $λ$ if and only if $A$ is the simple cycle matrix. Let $a_{i}$ be the signed sum of the determinants of the principal submatrices of $A$ of order $i \times i$ , $i = 1, ..., n - 1$ . We use similar techniques to Fiedler to show that Fiedler’s inequality can be strengthened to: $det (λ I - A) + \sum_{i = 1}^{n - 1} ρ^{n - 2 i} | a_{i} | {(λ - ρ)}^{i} \leq λ^{n} - ρ^{n}$ , for all $λ \geq ρ$ . We use this inequality to derive the inequality that: $\prod_{2}^{n} (ρ - λ_{i}) \leq ρ^{n - 2} \sum_{i = 2}^{n} (ρ - λ_{i})$ . In the spirit of a celebrated conjecture...

Vandermonde nets

Roswitha Hofer, Harald Niederreiter (2014)

Acta Arithmetica

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The second-named author recently suggested identifying the generating matrices of a digital (t,m,s)-net over the finite field $_{q}$ with an s × m matrix C over $_{q^{m}}$ . More exactly, the entries of C are determined by interpreting the rows of the generating matrices as elements of $_{q^{m}}$ . This paper introduces so-called Vandermonde nets, which correspond to Vandermonde-type matrices C, and discusses the quality parameter and the discrepancy of such nets. The methods that have been successfully used...