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Related papers: Weak Coherent States and their Path Integrals

200 papers

The model of weak measurements is applied to various problems, related to the time problem in quantum mechanics. The review and generalization of the theoretical analysis of the time problem in quantum mechanics based on the concept of weak…

Quantum Physics · Physics 2015-06-26 J. Ruseckas , B. Kaulakys

We analyze the quantum walk on a cycle using discrete Wigner functions as a way to represent the states and the evolution of the walker. The method provides some insight on the nature of the interference effects that make quantum and…

Quantum Physics · Physics 2009-11-10 C. C. Lopez , J. P. Paz

We re-use some original ideas of de~Broglie, Schr\"odiger, Dirac and Feynman to revise the ensemble interpretation of wave function in quantum mechanics. To this end we introduce coherence (auto-concordance) of ensembles of quantum…

Quantum Physics · Physics 2025-04-25 Vladimir V. Kisil

An approach to approximate evaluation of the continuum Feynman path integrals is developed for the study of quantum fluctuations of particles and fields in Euclidean time-space. The paths are described by sum of Gauss functions and are…

Quantum Physics · Physics 2012-06-20 Takayasu Sekihara

Coherent states, and the Hilbert space representations they generate, provide ideal tools to discuss classical/quantum relationships. In this paper we analyze three separate classical/quantum problems using coherent states, and show that…

Quantum Physics · Physics 2015-05-19 John R. Klauder

We discuss measures on spaces of unparametrized paths related to the Wiener measure. These measures arise naturally in the study of one-dimensional gravity coupled to scalar fields. Two kinds of discrete approximations are defined, the…

Mathematical Physics · Physics 2015-06-26 B. Durhuus , T. Jonsson

We consider weak values in the Feynman propagator framework, to gain a broader understanding of their interpretation in terms of path integrals. In particular, we examine the phenomenon of seemingly discontinuous paths that particles take…

Quantum Physics · Physics 2024-07-10 Shushmi Chowdhury , Jörg B. Götte

Non-Gaussian states, and specifically the paradigmatic Schr\"odinger cat state, are well-known to be very sensitive to losses. When propagating through damping channels, these states quickly loose their non-classical features and the…

Quantum Physics · Physics 2018-02-15 H. Le Jeannic , A. Cavaillès , K. Huang , R. Filip , J. Laurat

The state of a microscopic system encodes its complete quantum description, from which the probabilities of all measurement outcomes are inferred. Being a statistical concept, the state cannot be obtained from a single system realization.…

A quantum state can be written in phase space, but the resulting object is not generally the probability density of a positive stochastic process on ordinary phase space. We spell this out for Wigner dynamics. If a positive phase-space…

Quantum Physics · Physics 2026-05-08 Surachate Limkumnerd , Panat Phanthaphanitkul

Weak values, obtained from weak measurements, attempt to describe the properties of a quantum system as it evolves from an initial to a final state, without practically altering this evolution. Trajectories can be defined from weak…

Quantum Physics · Physics 2015-07-09 Alex Matzkin

We analyse some features of the class of discrete Wigner functions that was recently introduced by Gibbons et al. to represent quantum states of systems with power-of-prime dimensional Hilbert spaces [Phys. Rev. A 70, 062101 (2004)]. We…

Quantum Physics · Physics 2008-03-31 Cecilia Cormick , Juan Pablo Paz

Path integrals are a central tool when it comes to describing quantum or thermal fluctuations of particles or fields. Their success dates back to Feynman who showed how to use them within the framework of quantum mechanics. Since then, path…

Statistical Mechanics · Physics 2022-08-31 Leticia F. Cugliandolo , Vivien Lecomte , Frédéric Van Wijland

Feynman's path integrals provide a hidden variable description of quantum mechanics (and quantum field theories). The time evolution kernel is unitary in Minkowski time, but generically it becomes real and non-negative in Euclidean time. It…

Quantum Physics · Physics 2007-05-23 Apoorva Patel

The problem of combating de-coherence by weak measurements has already been studied for the amplitude damping channel and for specific input states. We generalize this to a large four-parameter family of qubit channels and for the average…

Quantum Physics · Physics 2024-05-31 Ozra Heibati , Azam Mani , Esfandiar Faizi , Vahid Karimipour

We employ the technique of weak measurement in order to enable preservation of teleportation fidelity for two-qubit noisy channels. We consider one or both qubits of a maximally entangled state to undergo amplitude damping, and show that…

Quantum Physics · Physics 2013-11-01 T. Pramanik , A. S. Majumdar

We develop the formulation of the spin(SU(2)) coherent state path integrals based on arbitrary fiducial vectors. The resultant action in the path integral expression extensively depends on the vector; It differs from the conventional one in…

Quantum Physics · Physics 2007-05-23 Masao Matsumoto

In this paper, the existence of weak solutions of a convective Cahn-Hilliard equation with degenerate mobility is studied. We first define a notion of weak solutions and establish a regularized problems. The existence of such solutions is…

Analysis of PDEs · Mathematics 2017-12-11 Xiaopeng Zhao

In quantum theory, a weak value is a complex number with a somewhat technical definition: it is a ratio whose numerator is the matrix element of a self-adjoint operator and whose denominator is the inner product of a corresponding pair of…

Quantum Physics · Physics 2026-02-11 Jacob A. Barandes

Coherent states in a projected Hilbert space have many useful properties. When there are conserved quantities, a representation of the entire Hilbert space is not necessary. The same issue arises when conditional observations are made with…

Quantum Physics · Physics 2016-12-28 P. D. Drummond , M. D. Reid