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Related papers: Effective Constraints for Quantum Systems

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Physical processes in the quantum regime possess non-classical properties of quantum mechanics. However, methods for quantitatively identifying such processes are still lacking. Accordingly, in this study, we develop a framework for…

Quantum Physics · Physics 2020-01-01 Chung-Cheng Kuo , Shih-Hsuan Chen , Wei-Ting Lee , Hung-Ming Chen , He Lu , Che-Ming Li

We introduce a general formalism, based on the stochastic formulation of quantum mechanics, to obtain localized quasi-classical wave packets as dynamically controlled systems, for arbitrary anharmonic potentials. The control is in general…

Quantum Physics · Physics 2008-11-26 Salvatore De Martino , Silvio De Siena , Fabrizio Illuminati

The relation between entanglement entropy and the computational difficulty of classically simulating Quantum Mechanics is briefly reviewed. Matrix product states are proven to provide an efficient representation of one-dimensional quantum…

Quantum Physics · Physics 2008-11-26 Jose I. Latorre

Constraints make hard optimization problems even harder to solve on quantum devices because they are implemented with large energy penalties and additional qubit overhead. The parity mapping, which has been introduced as an alternative to…

Quantum Physics · Physics 2023-03-20 Maike Drieb-Schön , Kilian Ender , Younes Javanmard , Wolfgang Lechner

A quantum-mechanical system comes naturally equipped with a convex space: each (Hermitian) operator has a (real) expectation value, and the expectation value of the square any Hermitian operator must be non-negative. This space is of…

High Energy Physics - Lattice · Physics 2025-02-05 Scott Lawrence

The commonly used circuit model of quantum computing leaves out the problems of imprecision in the initial state preparation, particle statistics (indistinguishability of particles belonging to the same quantum state), and error correction…

Quantum Physics · Physics 2007-05-23 Subhash Kak

This paper deals with a problem from discrete-time robust control which requires the solution of constraints over the reals that contain both universal and existential quantifiers. For solving this problem we formulate it as a program in a…

Logic in Computer Science · Computer Science 2007-05-23 Stefan Ratschan , Luc Jaulin

Various constraints concerning control fields can be imposed in the realistic implementations of quantum control systems. One of the most important is the restriction on the frequency spectrum of acceptable control parameters. It is…

Quantum Physics · Physics 2014-02-28 Łukasz Pawela , Zbigniew Puchała

We explore finite-field frameworks for quantum theory and quantum computation. The simplest theory, defined over unrestricted finite fields, is unnaturally strong. A second framework employs only finite fields with no solution to x^2+1=0,…

Quantum Physics · Physics 2015-06-15 Andrew J. Hanson , Gerardo Ortiz , Amr Sabry , Yu-Tsung Tai

This thesis addresses the problem of developing a quantum counter-part of the well established classical theory of control. We dwell on the fundamental fact that quantum states are generally not perfectly distinguishable, and quantum…

Quantum Physics · Physics 2009-08-21 Paulo E. M. F. Mendonca

Quantum confinement is studied by numerically solving time-dependent Schr\"odinger equation. An imaginary-time evolution technique is employed in conjunction with the minimization of an expectation value, to reach the global minimum.…

Quantum Physics · Physics 2018-01-31 Amlan K. Roy

Interpretation problems are eliminated from quantum theory by picturing a quantum history as having been sampled from a probability distribution over the set of histories which are permitted by all relevant boundary conditions. In…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Paul Sommers

Quantum linear system algorithms (QLSAs) for gate-based quantum computing can provide exponential speedups for solving linear systems but face challenges when applied to finite element problems due to the growth of the condition number with…

Quantum Physics · Physics 2023-10-20 Osama Muhammad Raisuddin , Suvranu De

The use of geometric methods has proved useful in the hamiltonian description of classical constrained systems. In this note we provide the first steps toward the description of the geometry of quantum constrained systems. We make use of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alejandro Corichi

We describe a broad dynamical-algebraic framework for analyzing the quantum control properties of a set of naturally available interactions. General conditions under which universal control is achieved over a set of subspaces/subsystems are…

Quantum Physics · Physics 2009-11-10 P. Zanardi , S. Lloyd

In the present article we consider the inverse fallacy, a well known cognitive heuristic experimentally tested in cognitive science, which occurs for intuitive judgments in situations of bounded rationality. We show that the quantum…

General Physics · Physics 2007-08-23 Riccardo Franco

An abstract formulation of quantum dynamics in the presence of a general set of quantum constraints is developed. Our constructive procedure is such that the relevant projection operator onto the physical Hilbert space is obtained with a…

High Energy Physics - Theory · Physics 2009-10-31 John R. Klauder

Starting with the first-order singular Lagrangian describing the dynamical system with 2nd-class constraints, the noncommutative quantum mechanics on a curved space is investigated by the constraint star-product quantization formalism of…

Quantum Physics · Physics 2017-06-29 M. Nakamura

The traditional framework of quantum metrology commonly assumes unlimited access to resources, overlooking resource constraints in realistic scenarios. As such, the optimal strategies therein can be infeasible in practice. Here, we…

Quantum Physics · Physics 2026-02-25 Longyun Chen , Yuxiang Yang

Precise definitions for different degrees of controllability for quantum systems are given, and necessary and sufficient conditions are discussed. The results are applied to determine the degree of controllability for various atomic systems…

Quantum Physics · Physics 2009-11-07 S. G. Schirmer , J. V. Leahy , A. I. Solomon
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