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Line integration of generalized functions is studied. Second order partial differential equations with piecewise continuous and generalized variable coefficients over Cayley-Dickson algebras are investigated. Formulas for integrations of…

Complex Variables · Mathematics 2018-12-18 S. V Ludkovsky

Let $\mathcal{A}$ be a unital $\mathbf{C}^*$-algebra with unit $e$. We develop several inequalities for a positive linear functional $f$ on $\mathcal{A}$ and obtain several bounds for the numerical radius $v(a)$ of an element $a\in…

Functional Analysis · Mathematics 2024-10-04 Pintu Bhunia

Given $n\in\mathbb{N}$ any point on the closed unit disk $\overline{\mathbb{D}}$ can be written as the average of $n$ points on the unit circle $\mathbb{S}^1$. Here we discuss a non-commutative version of this result. We prove that for any…

Functional Analysis · Mathematics 2025-11-19 Saptak Bhattacharya

Let $f \colon X \to B$ be a nonisotrivial complex elliptic surface and let $\mathcal{D} \subset X$ be an integral divisor dominating $B$. We study finiteness related properties of generalized $(S, \mathcal{D})$-integral sections $\sigma…

Algebraic Geometry · Mathematics 2019-12-17 Xuan Kien Phung

In this paper, we establish a generalization of Sturm--Picone comparison theorem for a pair of fractional nonlocal equations: \begin{eqnarray*} \begin{gathered} (-div. (A_1(x)\nabla))^{s} u = C_{1}(x) u \,\,\,\mbox{in}\,\,\Omega, u = 0…

Analysis of PDEs · Mathematics 2018-11-07 J. Tyagi

Let $\mathcal{S}_H^0$ denote the class of all functions $f(z)=h(z)+\overline{g(z)}=z+\sum^\infty_{n=2} a_nz^n +\overline{\sum^\infty_{n=2} b_nz^n}$ that are sense-preserving, harmonic and univalent in the open unit disk $|z|<1$. The…

Complex Variables · Mathematics 2017-03-08 Saminathan Ponnusamy , Anbareeswaran Sairam Kaliraj , Victor V. Starkov

We study renormalizations of piecewise smooth homeomorphisms on the circle, by considering such maps as generalized interval exchange maps of genus one. Suppose that $Df$ is absolutely continuous on each interval of continuity and…

Dynamical Systems · Mathematics 2019-03-20 Abdumajid Begmatov , Kleyber Cunha

An analytic function $f$ defined on the open unit disk $\mathbb{D}=\{z:|z|<1\}$ is bi-univalent if the function $f$ and its inverse $f^{-1}$ are univalent in $\mathbb{D}$. Estimates for the initial coefficients of bi-univalent functions $f$…

Complex Variables · Mathematics 2012-07-30 See Keong Lee , V. Ravichandran , Shamani Supramaniam

The article discusses criteria for univalence of analytic functions in the unit disc. Various families of analytic functions depending on real parameters are considered. A unified method for creating new sets of conditions ensuring…

Complex Variables · Mathematics 2013-03-06 D. Aharonov , U. Elias

Consider a continuous one parameter family of circles in complex plane that contains two circles lying in the exterior of one another. Under mild assumptions on the family, we prove that if a continuous function on the union of the above…

Complex Variables · Mathematics 2007-05-23 A. Tumanov

We count algebraic points of bounded height and degree on the graphs of certain functions analytic on the unit disk, obtaining a bound which is polynomial in the degree and in the logarithm of the multiplicative height. We combine this work…

Number Theory · Mathematics 2019-02-12 Gareth Boxall , Gareth Jones , Harry Schmidt

The main objects of study in this paper are those functionals that are analytic in the sense that they annihilate the non-commutative disc algebra. In the classical univariate case, a theorem of F. and M. Riesz implies that such functionals…

Operator Algebras · Mathematics 2021-04-07 Raphaël Clouâtre , Robert T. W. Martin , Edward J. Timko

We study the cyclicity of multipliers in Dirichlet-type spaces \( D_\alpha(\mathbb{B}_n) \). Specifically, we show that a multiplier \( f \) analytic on a neighborhood of $\overline{\mathbb{B}}_n$, whose zero set on the unit sphere is a…

Complex Variables · Mathematics 2026-03-03 Pouriya Torkinejad Ziarati

In the plane, we study the transform $R_\gamma f$ of integrating a unknown function $f$ over circles centered at a given curve $\gamma$. This is a simplified model of SAR, when the radar is not directed but has other applications, like…

Analysis of PDEs · Mathematics 2012-05-07 Plamen Stefanov , Gunther Uhlmann

We propose to visualize complex (meromorphic) functions $f$ by their phase $P_f:=f/|f|$. Color--coding the points on the unit circle converts the function $P_f$ to an image (the phase plot of $f$), which represents the function directly on…

Complex Variables · Mathematics 2010-07-15 Elias Wegert

We use the Aubry-Perret bound for singular curves, a generalization of the Hasse-Weil bound, to prove the following curious result about rational functions over finite fields: Let $f(X),g(X)\in\Bbb F_q(X)\setminus\{0\}$ be such that $q$ is…

Number Theory · Mathematics 2019-06-25 Xiang-dong Hou , Annamaria Iezzi

In this article, we obtain existence and uniqueness results to some problems involving complex nonlinear fractional differential equations (FDEs) in the closed unit disc of C. By help of these results, we prove that some IVPs for some…

Complex Variables · Mathematics 2017-07-18 M. Şan , K. N. Soltanov

Let D = {D_{1},...,D_{l}} be an arrangement of smooth hypersurfaces with normal crossings on the complex projective space P^n and let \Omega^{1}_{P^n}(log D) be the logarithmic bundle attached to it. Following [1], we show that…

Algebraic Geometry · Mathematics 2015-06-08 Elena Angelini

For the family of analytic functions $f(z)$ in the open unit disk $\mathbb{D}$ with $f(0)=f'(0)-1=0$, satisfying the differential equation \begin{equation*} zf'(z) - f(z) = \dfrac{1}{2} z^2 \phi(z), \quad |\phi(z)| \leq 1, \end{equation*}…

Complex Variables · Mathematics 2024-06-21 Prachi Prajna Dash , Jugal Kishore Prajapat

We reprove two results of Saltman, Theorem 5.1 and Corollary 5.2 of [Sa07]: If F is the function field of a smooth p-adic curve and D is an F-division algebra of prime degree l\neq p, then D is Z/l-cyclic, and that if D is an F-division…

Rings and Algebras · Mathematics 2014-02-06 Eric Brussel