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A statistical analysis of optimal universal cloning shows that it is possible to identify an ideal (but non-positive) copying process that faithfully maps all properties of the original Hilbert space onto two separate quantum systems. The…

Quantum Physics · Physics 2012-07-18 Holger F. Hofmann

Particle filtering is a numerical Bayesian technique that has great potential for solving sequential estimation problems involving non-linear and non-Gaussian models. Since the estimation accuracy achieved by particle filters improves as…

Computation · Statistics 2017-11-22 Jeyarajan Thiyagalingam , Lykourgos Kekempanos , Simon Maskell

Polar codes are the first error-correcting codes to provably achieve the channel capacity but with infinite codelengths. For finite codelengths the existing decoder architectures are limited in working frequency by the partial sums…

Hardware Architecture · Computer Science 2015-01-12 Guillaume Berhault , Camille Leroux , Christophe Jego , Dominique Dallet

This work presents a highly optimized computational framework for the Discrete Dipole Approximation, a numerical method for calculating the optical properties associated with a target of arbitrary geometry that is widely used in…

Instrumentation and Methods for Astrophysics · Physics 2009-08-07 James Mc Donald , Aaron Golden , S. Gerard Jennings

In this paper, we present an efficient algorithm to sample random sparse matrices to be used as check matrices for quantum Low-Density Parity-Check (LDPC) codes. To ease the treatment, we mainly describe our algorithm as a technique to…

Information Theory · Computer Science 2026-01-27 Paolo Santini

The precise description of quantum nuclear fluctuations in atomistic modelling is possible by employing path integral techniques, which involve a considerable computational overhead due to the need of simulating multiple replicas of the…

Chemical Physics · Physics 2017-03-23 Venkat Kapil , Jörg Behler , Michele Ceriotti

We study the problem of estimating the trace of a matrix $A$ that can only be accessed through matrix-vector multiplication. We introduce a new randomized algorithm, Hutch++, which computes a $(1 \pm \epsilon)$ approximation to $tr(A)$ for…

Data Structures and Algorithms · Computer Science 2021-06-14 Raphael A. Meyer , Cameron Musco , Christopher Musco , David P. Woodruff

Classical density functional theory (cDFT) provides a systematic approach to predict the structure and thermodynamic properties of chemical systems through the single-molecule density profiles. Whereas the statistical-mechanical framework…

Chemical Physics · Physics 2024-11-07 Jinni Yang , Runtong Pan , Jikai Sun , Jianzhong Wu

We describe recent progress in developing practical ab initio methods for which the computer effort is proportional to the number of atoms: linear scaling or O(N) methods. It is shown that the locality property of the density matrix gives a…

Condensed Matter · Physics 2007-05-23 D. R. Bowler , I. J. Bush , M. J. Gillan

This paper introduces an efficient algorithm for computing the general oscillatory matrix functions. These computations are crucial for solving second-order semi-linear initial value problems. The method is exploited using the scaling and…

Numerical Analysis · Mathematics 2024-06-11 Dongping Li , Xue Wang , Xiuying Zhang

We study faster algorithms for producing the minimum degree ordering used to speed up Gaussian elimination. This ordering is based on viewing the non-zero elements of a symmetric positive definite matrix as edges of an undirected graph, and…

Data Structures and Algorithms · Computer Science 2017-11-23 Matthew Fahrbach , Gary L. Miller , Richard Peng , Saurabh Sawlani , Junxing Wang , Shen Chen Xu

The fractional order system, which is described by the fractional order derivative and integral, has been studied in many engineering areas. Recently, the concept of fractional order has been generalized to the distributed order concept,…

Systems and Control · Computer Science 2013-12-12 Pham Luu Trung Duong , Moonyong Lee

Assume that f is a strict convex function with a unique minimum in R^n. We divide the vector of n-variables to d groups of vector subvariables with d at least two. We assume that we can find the partial minimum of f with respect to each…

Optimization and Control · Mathematics 2019-06-06 Shmuel Friedland

Fractional calculus is an effective tool in incorporating the effects of non-locality and memory into physical models. In this regard, successful applications exist rang- ing from signal processing to anomalous diffusion and quantum…

General Physics · Physics 2014-08-26 S. S. Bayin , J. P. Krisch

Implicit computational complexity is a lively area of theoretical computer science, which aims to provide machine-independent characterizations of relevant complexity classes. % for uniformity with subsequent uses >> 1960s (but feel free to…

Computational Complexity · Computer Science 2025-08-28 Melissa Antonelli , Arnaud Durand , Juha Kontinen

We present the basic idea, implementation, measured performance and performance model of FDPS (Framework for developing particle simulators). FDPS is an application-development framework which helps the researchers to develop particle-based…

Instrumentation and Methods for Astrophysics · Physics 2016-06-15 Masaki Iwasawa , Ataru Tanikawa , Natsuki Hosono , Keigo Nitadori , Takayuki Muranushi , Junichiro Makino

We describe an algorithm for arbitrary-precision computation of the elementary functions (exp, log, sin, atan, etc.) which, after a cheap precomputation, gives roughly a factor-two speedup over previous state-of-the-art algorithms at…

Numerical Analysis · Mathematics 2022-07-07 Fredrik Johansson

We propose a tomographic protocol for estimating any $ k $-body reduced density matrix ($ k $-RDM) of an $ n $-mode fermionic state, a ubiquitous step in near-term quantum algorithms for simulating many-body physics, chemistry, and…

Quantum Physics · Physics 2022-10-04 Andrew Zhao , Nicholas C. Rubin , Akimasa Miyake

Generating 2-by-2 unitary matrices in floating-precision arithmetic is a delicate task. One way to reduce the accumulation error is to use less floating-point operations to compute each of the entries in the 2-by-2 unitary matrix. This…

Numerical Analysis · Mathematics 2022-11-09 Weslley da Silva Pereira , Ali Lotfi , Julien Langou

We explore the utilization of higher-order discretization techniques in optimizing the gate count needed for quantum computer based solutions of partial differential equations. To accomplish this, we present an efficient approach for…

Quantum Physics · Physics 2024-12-30 Boris Arseniev , Dmitry Guskov , Richik Sengupta , Igor Zacharov
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