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We produce a Schwarz lemma for the symmetrized tridisc \[ \mathbb G_3 =\{ (z_1+z_2+z_3,z_1z_2+z_2z_3+z_3z_1,z_1z_2z_3): \,|z_i|< 1, i=1,2,3 \}. \] We show that an interpolating function related to the Schward lemma for $\mathbb G_3$ is not…

Complex Variables · Mathematics 2019-02-05 Sourav Pal , Samriddho Roy

We study the differential inclusion $Du\in K$, where $K$ is an unbounded and rotationally invariant subset of the real symmetric $3\times 3$ matrices. We exhibit a subset of all possible average fields. The corresponding microgeometries are…

Analysis of PDEs · Mathematics 2025-05-02 Nathan Albin , Vincenzo Nesi , Mariapia Palombaro

Bernstein-Nikolskii inequalities and Riesz interpolation formula are established for eigenfunctions of Laplace operators and polynomials on compact homogeneous manifolds.

Functional Analysis · Mathematics 2014-04-25 Isaac Z. Pesenson

We investigate the Pick problem for the polydisk and unit ball using dual algebra techniques. Some factorization results for Bergman spaces are used to describe a Pick theorem for any bounded region in $\mathbb{C}^d$.

Functional Analysis · Mathematics 2011-10-06 Ryan Hamilton

For two matrices in $\mathbb R^{n_1\times n_2}$, the von Neumann inequality says that their scalar product is less than or equal to the scalar product of their singular spectrum. In this short note, we extend this result to real tensors and…

Numerical Analysis · Mathematics 2015-02-06 Stéphane Chrétien , Tianwen Wei

Mueller polarimetry is a powerful technique with broad applications in astronomy, remote sensing, advanced material analysis, and biomedical imaging. However, instrumental constraints frequently restrict the measurement to an incomplete…

We prove a Caratheodory-Fejer type interpolation theorem for certain matrix convex sets in $\C^d$ using the Blecher-Ruan-Sinclair characterization of abstract operator algebras. Our results generalize the work of Dmitry S.…

Functional Analysis · Mathematics 2010-02-15 Sriram Balasubramanian

A class of trigonometric interpolation splines depending on parameter vectors, selected convergence factors and interpolation factors is considered. The concept of crosslink grids and interpolation grids is introduced; these grids can match…

Numerical Analysis · Mathematics 2020-11-13 Vldimir Denysiuk

It is known that the optimal Noether inequality $\mathrm{vol}(X) \ge \frac{4}{3}p_g(X) - \frac{10}{3}$ holds for every $3$-fold $X$ of general type with $p_g(X) \ge 11$. In this paper, we give a complete classification of $3$-folds $X$ of…

Algebraic Geometry · Mathematics 2022-04-06 Yong Hu , Tong Zhang

We establish the Noether inequality \[\textrm{Vol}(X)\geq \frac{4}{3}p_g(X)-\frac{10}{3}\] for all projective $3$-folds $X$ of general type with geometric genus $5\leq p_g(X)\leq 10$ where $\textrm{Vol}(X)$ is the canonical volume. This…

Algebraic Geometry · Mathematics 2025-08-26 Meng Chen , Yong Hu , Chen Jiang

We design convergent multipoint Pade interpolation schemes to Cauchy transforms of non-vanishing complex densities with respect to Jacobi-type weights on analytic arcs, under mild smoothness assumptions on the density. We rely on our…

Classical Analysis and ODEs · Mathematics 2010-10-25 Laurent Baratchart , Maxim Yattselev

Motivated by the recent progress of research on extending holomorphic functions defined on subvarieties of classical domains and its connections to the 3-point Pick interpolation, we study a special class of two-dimensional algebraic…

Complex Variables · Mathematics 2022-04-15 Krzysztof Maciaszek

This paper deals with the global well-posedness of the 3D axisymmetric Euler equations for initial data lying in critical Besov spaces $B_{p,1}^{1+3/p}$. In this case the BKM criterion is not known to be valid and to circumvent this…

Analysis of PDEs · Mathematics 2008-01-16 Hammadi Abidi , Taoufik Hmidi , Sahbi Keraani

We consider the Schur-Horn problem for normal operators in von Neumann algebras, which is the problem of characterizing the possible diagonal values of a given normal operator based on its spectral data. For normal matrices, this problem is…

Operator Algebras · Mathematics 2015-10-28 Matthew Kennedy , Paul Skoufranis

We prove some sharp inequalities for complex harmonic functions on the unit disk. The results extend a M. Riesz conjugate function theorem and some well-known estimates for holomorphic functions. We apply some of results to the…

Complex Variables · Mathematics 2017-01-20 David Kalaj

We present a complete system of inequalities for the inradius, circumradius, and diameter in the $3$-dimensional Euclidean space. To do so, we prove quasiconcavity of the inradius evaluated over $n$-simplices with a common facet…

Metric Geometry · Mathematics 2025-09-08 René Brandenberg , Bernardo González Merino , Mia Runge

An algorithm for generating interpolants for formulas which are conjunctions of quadratic polynomial inequalities (both strict and nonstrict) is proposed. The algorithm is based on a key observation that quadratic polynomial inequalities…

Logic in Computer Science · Computer Science 2016-11-14 Ting Gan , Liyun Dai , Bican Xia , Naijun Zhan , Deepak Kapur , Mingshuai Chen

We show that given three hermitian matrices, what one could call a fuzzy representation of a membrane, there is a well defined procedure to define a set of oriented Riemann surfaces embedded in $R^3$ using an index function defined for…

High Energy Physics - Theory · Physics 2013-05-30 David Berenstein , Eric Dzienkowski

We prove Ehrhard's inequality using interpolation along the Ornstein-Uhlenbeck semi-group. We also provide an improved Jensen inequality for Gaussian variables that might be of independent interest.

Probability · Mathematics 2016-05-25 Joe Neeman , Grigoris Paouris

For the bi-orthogonal polynomials with the third degree polynomial potential functions, the 3 x 3 matrix Riemann-Hilbert problem is explicitly constructed. The developed approach admits an extension to the bi-orthogonal polynomials with…

Exactly Solvable and Integrable Systems · Physics 2008-11-26 Andrei A. Kapaev