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Related papers: Computing the Quadratic Numerical Range

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We verify a conjecture on the structure of higher-rank numerical ranges for a wide class of unitary and normal matrices. Using analytic and geometric techniques, we show precisely how the higher-rank numerical ranges for a generic unitary…

Quantum Physics · Physics 2008-06-11 Man-Duen Choi , John A. Holbrook , David W. Kribs , Karol Zyczkowski

Large-scale quantum computation will only be achieved if experimentally implementable quantum error correction procedures are devised that can tolerate experimentally achievable error rates. We describe a quantum error correction procedure…

Quantum Physics · Physics 2011-02-22 David S. Wang , Austin G. Fowler , Lloyd C. L. Hollenberg

We propose a scheme for translating metrological precision bounds into lower bounds on query complexity of quantum search algorithms. Within the scheme the link between quadratic performance enhancement in idealized quantum metrological and…

Quantum Physics · Physics 2016-10-13 Rafal Demkowicz-Dobrzanski , Marcin Markiewicz

In this work, we analyze the variance of a stochastic estimator for computing Schatten norms of matrices. The estimator extracts information from a single sketch of the matrix, that is, the product of the matrix with a few standard Gaussian…

Numerical Analysis · Mathematics 2025-01-17 Ya-Chi Chu , Alice Cortinovis

Monte Carlo methods use random sampling to estimate numerical quantities which are hard to compute deterministically. One important example is the use in statistical physics of rapidly mixing Markov chains to approximately compute partition…

Quantum Physics · Physics 2017-07-12 Ashley Montanaro

Quantum phase estimation is one of the key algorithms in the field of quantum computing, but up until now, only approximate expressions have been derived for the probability of error. We revisit these derivations, and find that by ensuring…

Quantum Physics · Physics 2012-02-13 James M. Chappell , Max A. Lohe , Lorenz von Smekal , Azhar Iqbal , Derek Abbott

We present a quantum algorithm for efficiently sampling transformed Gaussian random fields on $d$-dimensional domains, based on an enhanced version of the classical moving average method. Pointwise transformations enforcing boundedness are…

Quantum Physics · Physics 2025-08-20 Matthias Deiml , Daniel Peterseim

Leverage score sampling is crucial to the design of randomized algorithms for large-scale matrix problems, while the computation of leverage scores is a bottleneck of many applications. In this paper, we propose a quantum algorithm to…

Quantum Physics · Physics 2023-09-19 Changpeng Shao

We introduce an effective algorithmic method for the computation of a lower bound for uniform expansion in one-dimensional dynamics. The approach employs interval arithmetic and thus provides a rigorous numerical result (computer-assisted…

Dynamical Systems · Mathematics 2026-01-28 Paweł Pilarczyk , Michał Palczewski , Stefano Luzzatto

An algorithm is presented which generates pairs of oscillatory random time series which have identical periodograms but differ in the number of oscillations. This result indicate the intrinsic limitations of spectral methods when it comes…

Data Analysis, Statistics and Probability · Physics 2007-05-23 A. G. Rossberg

This paper deals with the use of numerical methods based on random root sampling techniques to solve some theoretical problems arising in the analysis of polynomials. These methods are proved to be practical and give solutions where…

Numerical Analysis · Mathematics 2025-04-15 Yousra Gati , Vladimir Petrov Kostov , Mohamed Chaouki Tarchi

We give a semidefinite programming characterizations of the numerical radius and its dual norm for quaternionic matrices. We show that the computation of the numerical radius and its dual norm within $\varepsilon$ precision are polynomially…

Optimization and Control · Mathematics 2024-02-20 Shmuel Friedland

In this paper we address the complexity of solving linear programming problems with a set of differential equations that converge to a fixed point that represents the optimal solution. Assuming a probabilistic model, where the inputs are…

Computational Complexity · Computer Science 2007-05-23 Asa Ben-Hur , Joshua Feinberg , Shmuel Fishman , Hava T. Siegelmann

In this paper, we consider the nonconvex quadratically constrained quadratic programming (QCQP) with one quadratic constraint. By employing the conjugate gradient method, an efficient algorithm is proposed to solve QCQP that exploits the…

Optimization and Control · Mathematics 2018-07-17 Akram Taati , Maziar Salahi

We describe an approximate rational arithmetic with round-off errors (both absolute and relative) controlled by the user. The rounding procedure is based on the continued fraction expansion of real numbers. Results of computer experiments…

Numerical Analysis · Mathematics 2025-10-20 Grigori Litvinov , Anatoli Rodionov , Andrei Chourkin

The number of triangles in a graph is useful to deduce a plethora of important features of the network that the graph is modeling. However, finding the exact value of this number is computationally expensive. Hence, a number of…

Data Structures and Algorithms · Computer Science 2017-10-30 Duru Türkoğlu , Ata Turk

We present algorithms for nonparametric regression in settings where the data are obtained sequentially. While traditional estimators select bandwidths that depend upon the sample size, for sequential data the effective sample size is…

Methodology · Statistics 2012-07-03 Haijie Gu , John Lafferty

We obtain a sufficient condition for the convexity of quaternionic numerical range for complex matrices in terms of its complex numerical range. It is also shown that the Bild coincides with complex numerical range for real matrices. From…

Functional Analysis · Mathematics 2019-04-08 Luís Carvalho , Cristina Diogo , Sérgio Mendes

The question of what can be computed, and how efficiently, are at the core of computer science. Not surprisingly, in distributed systems and networking research, an equally fundamental question is what can be computed in a…

Distributed, Parallel, and Cluster Computing · Computer Science 2016-04-01 Fabian Kuhn , Thomas Moscibroda , Roger Wattenhofer

In this paper, a class of optimization problems with nonlinear inequality constraints is discussed. Based on the ideas of sequential quadratic programming algorithm and the method of strongly sub-feasible directions, a new superlinearly…

Optimization and Control · Mathematics 2012-06-28 Jin-Bao Jian , Chuan-Hao Guo , Chun-Ming Tang , Yan-Qin Bai
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