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Related papers: Weak Decoherence and Quantum Trajectory Graphs

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The weak regular coherence is a coarse property of a finitely generated group $\Gamma$. It was introduced by G. Carlsson and this author to play the role of a weakening of Waldhausen's regular coherence as part of computation of the…

Geometric Topology · Mathematics 2018-07-16 Boris Goldfarb

We investigate the quantum walk on the line when decoherences are introduced either through simultaneous measurements of the chirality and particle position, or as a result of broken links. Both mechanisms drive the system to a classical…

Quantum Physics · Physics 2009-11-10 A. Romanelli , R. Siri , G. Abal , A. Auyuanet , R. Donangelo

We consider the effect of different unitary noise mechanisms on the evolution of a quantum walk (QW) on a linear chain with a generic coin operation: (i) bit-flip channel noise, restricted to the coin subspace of the QW, and (ii)…

Quantum Physics · Physics 2007-11-27 G. Abal , R. Donangelo , F. Severo , R. Siri

Quantum trajectories describe the stochastic evolution of an open quantum system conditioned on continuous monitoring of its output, such as by an ideal photodetector. In practice an experimenter has access to an output filtered through…

Quantum Physics · Physics 2016-09-08 P. Warszawski , H. M. Wiseman

We study the decoherence dynamics of a qubit coupled to a quantum two-level system (TLS) in addition to its weak coupling to a background environment. We analyze the different regimes of behaviour that arise as the values of the different…

Superconductivity · Physics 2007-05-23 S. Ashhab , J. R. Johansson , Franco Nori

We have studied how decoherence affects a quantum walk on the line. As expected, it is highly sensitive, consisting as it does of an extremely delocalized particle. We obtain an expression for the rate at which the standard deviation falls…

Quantum Physics · Physics 2007-05-23 Viv Kendon , Ben Tregenna

The concept of presence has been extensively explored in philosophy, yet the notion of particle presence within quantum theory remains under-examined. In this article, we explore particle presence through an analysis of a paradox arising…

History and Philosophy of Physics · Physics 2025-03-26 Bethany Terris

It is proposed to improve the quality of a variational description of a closed quantum system by adding ficticious dissipation that reduces the entanglement. The proposal is implemented for a small Bose-Hubbard chain, which shows chaotic…

Quantum Gases · Physics 2020-10-28 Michiel Wouters

This paper explores the possibility that an exactly decoherent set of histories may be constructed from an approximately decoherent set by small distortions of the operators characterizing the histories. In particular, for the case of…

Quantum Physics · Physics 2009-11-06 J. J. Halliwell

Recently several quantum search algorithms based on quantum walks were proposed. Those algorithms differ from Grover's algorithm in many aspects. The goal is to find a marked vertex in a graph faster than classical algorithms. Since the…

Quantum Physics · Physics 2012-05-18 G. Abal , R. Donangelo , F. L. Marquezino , A. C. Oliveira , R. Portugal

Gravitational decoherence (GD) refers to the effects of gravity in actuating the classical appearance of a quantum system. Because the underlying processes involve issues in general relativity (GR), quantum field theory (QFT) and quantum…

General Relativity and Quantum Cosmology · Physics 2024-06-19 Charis Anastopoulos , Bei-Lok Hu

We connect the weak measurements framework to the path integral formulation of quantum mechanics. We show how Feynman propagators can in principle be experimentally inferred from weak value measurements. We also obtain expressions for weak…

Quantum Physics · Physics 2020-09-09 A. Matzkin

We have studied the quantum oscillations of the conductance for arrays of connected mesoscopic metallic rings, in the presence of an external magnetic field. Several geometries have been considered: a linear array of rings connected with…

Disordered Systems and Neural Networks · Physics 2009-12-26 Christophe Texier , Pierre Delplace , Gilles Montambaux

In quantum physics, measurement results are random but their statistics can be predicted assuming some knowledge about the system in the past. Additional knowledge from a future measurement deeply changes the statistics in the present and…

We use a $\lambda\Phi^4$ scalar quantum field theory to illustrate a new approach to the study of quantum to classical transition. In this approach, the decoherence functional is employed to assign probabilities to consistent histories…

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. Calzetta , B. L. Hu

The computation of the optical conductivity of strained and deformed graphene is discussed within the framework of quantum field theory in curved spaces. The analytical solutions of the Dirac equation in an arbitrary static background…

Materials Science · Physics 2015-12-01 W. de Paula , a. Chaves , O. Oliveira , T. Frederico

The quantum theory of decoherence plays an important role in a pragmatist interpretation of quantum theory. It governs the descriptive content of claims about values of physical magnitudes and offers advice on when to use quantum…

Quantum Physics · Physics 2012-07-30 Richard Healey

Self-induced decoherence formalism and the corresponding classical limit are extended from quantum integrable systems to non-integrable ones.

Quantum Physics · Physics 2007-05-23 Mario Castagnino

There are still no interacting models of the Wightman axioms, suggesting that the axioms are too tightly drawn. Here a weakening of linearity for quantum fields is proposed, with the algebra still linear but with the quantum fields no…

Quantum Physics · Physics 2007-05-23 Peter Morgan

We study the disordered quantum walk in one dimension, and obtain the weak limit theorem.

Mathematical Physics · Physics 2011-09-01 Clement Ampadu