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Related papers: Multichannel Quantum Defect Theory: a Quantum Poin…

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The concept of multiple particle interference is discussed, using insights provided by the classical theory of error correcting codes. This leads to a discussion of error correction in a quantum communication channel or a quantum computer.…

Quantum Physics · Physics 2009-10-30 Andrew Steane

Errors are the fundamental barrier to the development of quantum systems. Quantum networks are complex systems formed by the interconnection of multiple components and suffer from error accumulation. Characterizing errors introduced by…

Quantum decision theory (QDT) is a recently developed theory of decision making based on the mathematics of Hilbert spaces, a framework known in physics for its application to quantum mechanics. This framework formalizes the concept of…

Physics and Society · Physics 2016-12-28 M. Favre , A. Wittwer , H. R. Heinimann , V. I. Yukalov , D. Sornette

Modal quantum theory (MQT) is a "toy model" of quantum theory in which amplitudes are elements of a general field. The theory predicts, not the probabilities of a measurement result, but only whether or not a result is possible. In this…

Quantum Physics · Physics 2015-06-04 Benjamin Schumacher , Michael D. Westmoreland

There is a long history of representing a quantum state using a quasi-probability distribution: a distribution allowing negative values. In this paper we extend such representations to deal with quantum channels. The result is a convex,…

Quantum Physics · Physics 2018-03-05 John van de Wetering

We extend the powerful formalism of multichannel quantum defect theory combined with a frame transformation to ultracold atom-molecule collisions in magnetic fields. By solving the coupled-channel equations with hyperfine and Zeeman…

Chemical Physics · Physics 2024-09-10 Masato Morita , Paul Brumer , Timur V. Tscherbul

One of the most challenging open problems in quantum information theory is to clarify and quantify how entanglement behaves when part of an entangled state is sent through a quantum channel. Of central importance in the description of a…

Quantum Physics · Physics 2007-05-23 Frank Verstraete , Henri Verschelde

We argue that notions in quantum theory should have universal properties in the sense of category theory. We consider the completely positive trace preserving (CPTP) maps, the basic notion of quantum channel. Physically, quantum channels…

Quantum Physics · Physics 2019-01-30 Mathieu Huot , Sam Staton

Quantum Phase Transition (QPT) is a phase transition between different quantum states by adjusting some control parameters. Based on the Principle of Hamilton Dynamics (PHD) and the Principle of Lagrangian Dynamics (PLD), a general QPT…

Analysis of PDEs · Mathematics 2016-12-09 Tian Ma , Da-peng Li , Ruikuan Liu , Jiayan Yang

As the rapidly evolving field of machine learning continues to produce incredibly useful tools and models, the potential for quantum computing to provide speed up for machine learning algorithms is becoming increasingly desirable. In…

Quantum Physics · Physics 2024-04-02 Anthony M. Smaldone , Gregory W. Kyro , Victor S. Batista

This is a comprehensive review of the random-matrix approach to the theory of phase-coherent conduction in mesocopic systems. The theory is applied to a variety of physical phenomena in quantum dots and disordered wires, including universal…

Mesoscale and Nanoscale Physics · Physics 2008-02-03 C. W. J. Beenakker

Quantum machine learning (QML) leverages quantum computing for classical inference, furnishes the processing of quantum data with machine-learning methods, and provides quantum algorithms adapted to noisy devices. Typically, QML proposals…

Quantum Physics · Physics 2026-05-11 Luis Mantilla Calderón , Robert Raussendorf , Polina Feldmann , Dmytro Bondarenko

Peculiarities of multiqubit measurement are for the most part similar to peculiarities of measurement for qudit -- quantum object with finite-dimensional Hilbert space. Three different interpretations of measurement concept are analysed.…

Quantum Physics · Physics 2024-06-13 Constantin Usenko

The quantum deformed (1+1) Poincare' algebra is shown to be the kinematical symmetry of the harmonic chain, whose spacing is given by the deformation parameter. Phonons with their symmetries as well as multiphonon processes are derived from…

High Energy Physics - Theory · Physics 2009-10-22 F. Bonechi , E. Celeghini , R. Giachetti , E. Sorace , M. Tarlini

Quantum superchannels are maps whose input and output are quantum channels. Rather than taking the domain to be the space of all linear maps we motivate and define superchannels on the operator system spanned by quantum channels. Extension…

Quantum Physics · Physics 2022-10-04 Pádraig Daly

Quantum Monte Carlo methods provide in principle an accurate treatment of the many-body problem of the ground and excited states of condensed systems. In practice, however, uncontrolled errors such as those arising from the fixed-node and…

Materials Science · Physics 2012-03-27 William W. Tipton , Neil D. Drummond , Richard G. Hennig

The Python functions distributed with this article can be used for calculating the parameters of multichannel quantum defect theory models describing excited bound states of complex atoms. These parameters are obtained by fitting a model to…

Atomic Physics · Physics 2024-09-20 R. M. Potvliege

We present a quantum theory of ion-atom interaction that is applicable at energies comparable to or smaller than the atomic hyperfine splitting and takes proper account of the effects of identical nuclei. The theory reveals the subtlety and…

Atomic Physics · Physics 2015-06-18 Ming Li , Li You , Bo Gao

By introducing an operator sum representation for arbitrary linear maps, we develop a generalized theory of quantum error correction (QEC) that applies to any linear map, in particular maps that are not completely positive (CP). This theory…

Quantum Physics · Physics 2009-10-21 A. Shabani , D. A. Lidar

Unital quantum channels, defined by their property of leaving the maximally mixed state invariant, form an important class of quantum operations. A distinguished subset of these channels can be represented as a probabilistic mixture of…

Quantum Physics · Physics 2026-03-19 Charlotte Bäcker , Konstantin Beyer , Walter T. Strunz