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Related papers: Classical Complexity of Unitary Transformations

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We give a basic overview of computational complexity, query complexity, and communication complexity, with quantum information incorporated into each of these scenarios. The aim is to provide simple but clear definitions, and to highlight…

Quantum Physics · Physics 2016-11-23 Richard Cleve

A formalism is developed for describing approximate classical behaviour in finite (but possibly large) quantum systems. This is done in terms of a structure common to classical and quantum mechanics, viz. a Poisson space with a transition…

Quantum Physics · Physics 2015-06-26 N. P. Landsman

Constrained Hamiltonian description of the classical limit is utilized in order to derive consistent dynamical equations for hybrid quantum-classical systems. Starting with a compound quantum system in the Hamiltonian formulation conditions…

Quantum Physics · Physics 2012-06-08 M. Radonjic , S. Prvanovic , N. Buric

We consider a constructive modification of quantum-mechanical formalism. Replacement of a general unitary group by unitary representations of finite groups makes it possible to reproduce quantum formalism without loss of its empirical…

General Physics · Physics 2018-03-02 Vladimir V. Kornyak

The complexity and the chaos degree can be used to examine the chaotic aspects of not only several nonlinear classical and quantum physical physics but also life sciences. We will construct a model describing the function of brain in the…

Quantum Physics · Physics 2007-05-23 Masanori Ohya

The claim that there is an inconsistency of quantum-classical dynamics [1] is investigated. We point out that a consistent formulation of quantum and classical dynamics which can be used to describe quantum measurement processes is already…

Quantum Physics · Physics 2007-05-23 E. C. G. Sudarshan

We estimate the proportion of several classes of elements in finite classical groups which are readily recognised algorithmically, and for which some power has a large fixed point subspace and acts irreducibly on a complement of it. The…

Group Theory · Mathematics 2014-05-13 Alice C. Niemeyer , Cheryl E. Praeger

The emergence of quantum computing proposes a revolutionary paradigm that can radically transform numerous scientific and industrial application domains. The ability of quantum computers to scale computations exponentially imply better…

Software Engineering · Computer Science 2024-03-29 Vlad Stirbu , Tommi Mikkonen

Representations of quantum computations are almost always based on a tensor product $\otimes$-structure. This coincides with what we are able to execute in our experiments, as well as what we observe in Nature, but it makes certain familiar…

Quantum Physics · Physics 2021-11-05 Luca Mondada

A discrete complexified quaternion Fourier transform is introduced. This is a generalization of the discrete quaternion Fourier transform to the case where either or both of the signal/image and the transform kernel are complex…

Numerical Analysis · Mathematics 2008-03-19 Salem Said , Nicolas Le Bihan , Stephen J. Sangwine

Classical-quantum computational complexity separations are an important motivation for the long-term development of digital quantum computers, but classical-quantum complexity equivalences are just as important in our present era of noisy…

Quantum Physics · Physics 2020-03-10 Jonathan E. Moussa

Quantum machine learning (QML) holds promise for accelerating pattern recognition, optimization, and data analysis, but the conditions under which it can truly outperform classical approaches remain unclear. Existing research often…

Quantum Physics · Physics 2025-09-23 Christophe Pere

In this paper we give a definition for the Kolmogorov complexity of a pure quantum state. In classical information theory the algorithmic complexity of a string is a measure of the information needed by a universal machine to reproduce the…

Quantum Physics · Physics 2007-05-23 C. Mora , H. J. Briegel

Using a quantumlike description for light propagation in nonhomogeneous optical fibers, quantum information processing can be implemented by optical means. Quantum-like bits (qulbits) are associated to light modes in the optical fiber and…

Quantum Physics · Physics 2009-11-07 M. A. Man'ko , V. I. Man'ko , R. Vilela Mendes

This article traces a brief history of the use of single electron spins to compute. In classical computing schemes, a binary bit is represented by the spin polarization of a single electron confined in a quantum dot. If a weak magnetic…

Mesoscale and Nanoscale Physics · Physics 2011-02-01 S. Bandyopadhyay

In this article we propose a solution to the measurement problem in quantum mechanics. We point out that the measurement problem can be traced to an a priori notion of classicality in the formulation of quantum mechanics. If this notion of…

Quantum Physics · Physics 2008-11-26 Olaf Dreyer

This chapter does not deal with specific tools and techniques for managing complex systems, but proposes some basic concepts that help us to think and speak about complexity. We review classical thinking and its intrinsic drawbacks when…

Adaptation and Self-Organizing Systems · Physics 2007-05-23 Carlos Gershenson , Francis Heylighen

We show that semiclassical formulas such as the Gutzwiller trace formula can be implemented on a quantum computer more efficiently than on a classical device. We give explicit quantum algorithms which yield quantum observables from…

Quantum Physics · Physics 2008-09-03 B. Georgeot , O. Giraud

Classical complexity theory measures the cost of computing a function, but many computational tasks require committing to one valid output among several. We introduce determination depth -- the minimum number of sequential layers of…

Computational Complexity · Computer Science 2026-04-08 Joseph M. Hellerstein

The nongeneric six- and eightdimensional orbits of SO(4,2) are described in explicitly covariant way. The relevant Hamiltonian dynamical systems are constructed and canonically quantized. It is shown that the resulting unitary…

High Energy Physics - Theory · Physics 2023-07-27 Piotr Kosinski , Pawel Maslanka