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Related papers: Quantum measurement and decoherence

200 papers

The quantum nature of gravity remains an open question in fundamental physics, lacking experimental verification. Gravitational waves (GWs) provide a potential avenue for detecting gravitons, the hypothetical quantum carriers of gravity.…

General Relativity and Quantum Cosmology · Physics 2025-06-04 Hiroki Takeda , Takahiro Tanaka

We study the problem of driving an unknown initial mixed quantum state onto a known pure state without using unitary transformations. This can be achieved, in an efficient manner, with the help of sequential measurements on at least two…

Quantum Physics · Physics 2009-11-11 L. Roa , G. Olivares

An emergent theory of quantum measurement arises directly by considering the particular subset of many body wavefunctions that can be associated with classical condensed matter and its interaction with delocalized wavefunctions. This…

Quantum Physics · Physics 2015-03-03 Clifford Chafin

Recently, several studies of neutrino oscillations in the vacuum have not found the decoherence long expected from the separation of wave packets of neutrinos in different mass eigenstates. We show that such decoherence will, on the other…

High Energy Physics - Phenomenology · Physics 2022-12-21 Emilio Ciuffoli , Jarah Evslin

This paper presents arguments purporting to show that von Neumann's description of the measurement process in quantum mechanics has a modern day version in the decoherence approach. We claim that this approach and the de Broglie-Bohm theory…

Quantum Physics · Physics 2007-05-23 L. F. Santos , C. O. Escobar

Decoherence is the process via which quantum superpositions states are reduced to classical mixtures. Decoherence has been predicted for relativistically accelerated quantum systems, however examples to date have involved restricting the…

Quantum Physics · Physics 2019-01-16 Daiqin Su , Timothy C. Ralph

A simplified Heisenberg spin model is studied in order to examine the idea of decoherence in closed quantum systems. For this purpose, we present a quantifiable definition to quantum coherence $\Xi$, and discuss in some detail a general…

Quantum Physics · Physics 2008-05-18 Olavi Dannenberg

Continuous quantum measurement is the backbone of various methods in quantum control, quantum metrology, and quantum information. Here, we present a generalized formulation of dispersive measurement of a complex quantum systems. We describe…

Quantum Physics · Physics 2014-04-29 A. Shabani , J. Roden , K. B. Whaley

We prove a quantum version of the second law of thermodynamics: the (quantum) Boltzmann entropy increases if the initial (zero time) density matrix decoheres, a condition generally satisfied in Nature. It is illustrated by a model of…

Mathematical Physics · Physics 2015-06-17 H. Narnhofer , W. F. Wreszinski

The analysis of the modifications that the presence of a deformed dispersion relation entails in the roots of the so--called degree of coherence function, for a beam embodying two different frequencies and moving in a Michelson…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. Camacho , A. Macias

Quantum decoherence arises due to uncontrollable entanglement between a system with its environment. However the effects of decoherence are often thought of and modeled through a simpler picture in which the role of the environment is to…

Quantum Physics · Physics 2019-09-17 Bing Gu , Ignacio Franco

Quantum decoherence is of primary importance for relaxation to an equilibrium distribution and, accordingly, for equilibrium processes. We demonstrate how coherence breaking implies evolution to a microcanonical distribution…

Quantum Physics · Physics 2008-02-03 Stefan V. Mashkevich , Vladimir S. Mashkevich

The diffusion coefficient--a measure of dissipation, and the entropy--a measure of fluctuation are found to be intimately correlated in many physical systems. Unlike the fluctuation dissipation theorem in linear response theory, the…

Statistical Mechanics · Physics 2021-03-25 Yi Liao , Xiao-Bo Gong

The interplay of unitary evolution and local measurements in many-body systems gives rise to a stochastic state evolution and to measurement-induced phase transitions in the pure state entanglement. In realistic settings, however, this…

Statistical Mechanics · Physics 2022-08-23 B. Ladewig , S. Diehl , M. Buchhold

We prove analytical results showing that decoherence can be useful for mixing time in a continuous-time quantum walk on finite cycles. This complements the numerical observations by Kendon and Tregenna (Physical Review A 67 (2003), 042315)…

Quantum Physics · Physics 2007-05-23 Leonid Fedichkin , Dmitry Solenov , Christino Tamon

We consider the decoherence of phase space histories in a class of quantum Brownian motion models, consisting of a particle moving in a potential $V(x)$ in interaction with a heat bath at temperature $T$ and dissipation gamma, in the…

Quantum Physics · Physics 2009-10-28 C. Anastopoulos

If a quantum experiment includes random processes, then the results of repeated measurements can appear consistent with irreversible decoherence even if the system's evolution prior to measurement was reversible and unitary. Two thought…

Quantum Physics · Physics 2012-06-01 Sam Kennerly

Decoherence is well understood, in contrast to disentanglement. According to common lore, irreversible coupling to a dissipative environment is the mechanism for loss of entanglement. Here, we show that, on the contrary, disentanglement can…

Quantum Physics · Physics 2015-05-20 G. W. Ford , R. F. O'Connell

A theory recently proposed by the author aims to explain decoherence and the thermodynamical behaviour of closed systems within a conservative, unitary, framework for quantum gravity by assuming that the operators tied to the gravitational…

High Energy Physics - Theory · Physics 2010-04-06 Bernard S. Kay

An unstable quantum state generally decays following an exponential law, as environmental decoherence is expected to prevent the decay products from recombining to reconstruct the initial state. Here we show the existence of deviations from…

Quantum Physics · Physics 2017-10-02 M. Beau , J. Kiukas , I. L. Egusquiza , A. del Campo