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A two dimensional eigenvalue problem (2DEVP) of a Hermitian matrix pair $(A, C)$ is introduced in this paper. The 2DEVP can be viewed as a linear algebraic formulation of the well-known eigenvalue optimization problem of the parameter…

Numerical Analysis · Mathematics 2022-09-19 Yangfeng Su , Tianyi Lu , Zhaojun Bai

A radar system emits probing signals and records the reflections. Estimating the relative angles, delays, and Doppler shifts from the received signals allows to determine the locations and velocities of objects. However, due to practical…

Information Theory · Computer Science 2018-10-09 Reinhard Heckel

Pairwise learning focuses on learning tasks with pairwise loss functions, depends on pairs of training instances, and naturally fits for modeling relationships between pairs of samples. In this paper, we focus on the privacy of pairwise…

Machine Learning · Computer Science 2021-06-02 Yilin Kang , Yong Liu , Jian Li , Weiping Wang

Distributionally robust optimization is used to tackle decision making problems under uncertainty where the distribution of the uncertain data is ambiguous. Many ambiguity sets have been proposed for continuous uncertainty that build on…

Optimization and Control · Mathematics 2025-05-28 Karthik Natarajan , Divya Padmanabhan , Arjun Ramachandra

Various practical problems within the class $\Sigma_{2}^P$ possess an unambiguity property, meaning that yes-instances correspond with a unique witness. The semantic class containing all unambiguous $\Sigma_{2}^P$ problems is denoted…

Computational Complexity · Computer Science 2026-04-02 Matan Gilboa , Paul W. Goldberg , Elias Koutsoupias , Noam Nisan

We study factorizations of rational matrix functions with simple poles on the Riemann sphere. For the quadratic case (two poles) we show, using multiplicative representations of such matrix functions, that a good coordinate system on this…

Mathematical Physics · Physics 2013-02-14 Anton Dzhamay

We study the emptiness and $\lambda$-reachability problems for unary and binary Probabilistic Finite Automata (PFA) and characterise the complexity of these problems in terms of the degree of ambiguity of the automaton and the size of its…

Formal Languages and Automata Theory · Computer Science 2024-02-14 Paul C. Bell , Pavel Semukhin

Riemann-Hilbert problems are jump problems for holomorphic functions along given interfaces. They arise in various contexts, e.g. in the asymptotic study of certain nonlinear partial differential equations and in the asymptotic analysis of…

Complex Variables · Mathematics 2024-04-05 Haakan Hedenmalm

Reciprocal transformations mix the role of the dependent and independent variables to achieve simpler versions or even linearized versions of nonlinear PDEs. These transformations help in the identification of a plethora of PDEs available…

Mathematical Physics · Physics 2016-04-08 C. Sardon

We propose ARDO method for solving PDEs and PDE-related problems with deep learning techniques. This method uses a weak adversarial formulation but transfers the random difference operator onto the test function. The main advantage of this…

Numerical Analysis · Mathematics 2025-09-05 Wei Cai , Andrew Qing He

Many problems in physics, chemistry and other fields are perturbative in nature, i.e. differ only slightly from related problems with known solutions. Prominent among these is the eigenvalue perturbation problem, wherein one seeks the…

Mathematical Physics · Physics 2020-03-12 Maseim Kenmoe , Matteo Smerlak , Anton Zadorin

We develop a duality theory for unbounded Hermitian operators with dense domain in Hilbert space. As is known, the obstruction for a Hermitian operator to be selfadjoint or to have selfadjoint extensions is measured by a pair of deficiency…

Mathematical Physics · Physics 2009-04-13 Palle E. T. Jorgensen

In this article, a posteriori error analysis of the elliptic obstacle problem is addressed using hybrid high-order methods. The method involve cell unknowns represented by degree-$r$ polynomials and face unknowns represented by degree-$s$…

Numerical Analysis · Mathematics 2024-05-09 Kamana Porwal , Ritesh Singla

We introduce a dbar-formulation of the orthogonal polynomials on the complex plane, and hence of the related normal matrix model, which is expected to play the same role as the Riemann-Hilbert formalism in the theory of orthogonal…

Classical Analysis and ODEs · Mathematics 2007-08-30 Alexander R. Its , Leon A. Takhtajan

We study the asymptotic behavior of positive radial solutions for quasilinear elliptic systems that have the form \begin{equation*} \left\{ \begin{aligned} \Delta_p u &= c_1|x|^{m_1} \cdot g_1(v) \cdot |\nabla u|^{\alpha} &\quad\mbox{ in }…

Analysis of PDEs · Mathematics 2023-07-04 Daniel Devine , Paschalis Karageorgis

The minimisation problem of a sum of unary and pairwise functions of discrete variables is a general NP-hard problem with wide applications such as computing MAP configurations in Markov Random Fields (MRF), minimising Gibbs energy, or…

Computational Complexity · Computer Science 2014-01-24 Martin C. Cooper , Stanislav Živný

We propose a fast greedy algorithm to compute sparse representations of signals from continuous dictionaries that are factorizable, i.e., with atoms that can be separated as a product of sub-atoms. Existing algorithms strongly reduce the…

Signal Processing · Electrical Eng. & Systems 2020-12-01 Gilles Monnoyer de Galland , Luc Vandendorpe , Laurent Jacques

In this paper, by making use of a certain family of fractional derivative operators in the complex domain, we introduce and investigate a new subclass $\mathcal{P}_{\tau,\mu}(k,\delta,\gamma)$ of analytic and univalent functions in the open…

Complex Variables · Mathematics 2015-11-06 Zainab Esa , H. M. Srivastava , Adem Kilicman , Rabha W. Ibrahim

We propose a framework for a new type of finite field theories based on a hidden duality between an ultra-violet and an infra-red region. Physical quantities do not receive radiative corrections at a fundamental scale or the fixed point of…

High Energy Physics - Phenomenology · Physics 2015-03-18 Yoshiharu Kawamura

In the field of radial basis functions mathematicians have been endeavouring to find infinitely differentiable and compactly supported radial functions. This kind of functions is extremely important. One of the reasons is that its error…

Numerical Analysis · Mathematics 2007-05-23 Lin-Tian Luh