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Related papers: Weak Coherent State Path Integrals

200 papers

The aim of this article is to study a Cahn-Hilliard model for a multicomponent mixture with cross-diffusion effects, degenerate mobility and where only one of the species does separate from the others. We define a notion of weak solution…

Analysis of PDEs · Mathematics 2020-07-03 Virginie Ehrlacher , Greta Marino , Jan-Frederik Pietschmann

In the paper our aim was to study the properties of a new version of coherent states whose argument is a linear combination of two special singular square 2 x 2 matrix, having a single nonzero element, equal to 1, and two labeling complex…

Quantum Physics · Physics 2026-02-02 Dušan Popov

In these notes, we elucidate some subtle aspects of coherent-state path integrals, focusing on their application to the equilibrium thermodynamics of quantum many-particle systems. These subtleties emerge when evaluating path integrals in…

Quantum Gases · Physics 2026-02-19 Luca Salasnich , Cesare Vianello

We employ the path integral approach developed in [29] to discuss the (generalized) harmonic oscillator in a noncommutative plane. The action for this system is derived in the coherent state basis with additional degrees of freedom. From…

High Energy Physics - Theory · Physics 2015-06-30 Sunandan Gangopadhyay

We investigate the time evolution of a superposition of macroscopically distinct quantum states in a system of two-level atoms interacting with a thermal environment of photon modes. We show that the atomic coherent states are robust…

Quantum Physics · Physics 2015-06-26 Peter Foldi , Attila Czirjak , Mihaly G. Benedict

In applying the stationary phase approximation to coherent state path integrals a difficulty occurs; there are no classical paths that satisfy the boundary conditions of the path integral. Others have gotten around this problem by…

Mathematical Physics · Physics 2007-05-23 Chris Ray , Giulio Ruffini

The paper solves the problem of continuum limit in bosonic thermal coherent-state path integrals. For this purpose, exact discrete versions of the path integral are constructed for three different orderings of the Hamiltonian: normal,…

Quantum Physics · Physics 2026-02-03 Oliwier Urbański

There are no phase-space trajectories for anharmonic quantum systems, but Wigner's phase-space representation of quantum mechanics features Wigner current~$\bf J$. This current reveals fine details of quantum dynamics -- finer than is…

Quantum Physics · Physics 2017-09-11 Dimitris Kakofengitis , Ole Steuernagel

Unitarity is a difficult concept to implement in canonical quantum gravity because of state non-normalizability and the problem of time. We take a realist approach based on pilot-wave theory to address this issue in the Ashtekar formulation…

General Relativity and Quantum Cosmology · Physics 2024-05-07 Indrajit Sen , Stephon Alexander , Justin Dressel

We prove the existence of a weak solution to the equations describing the inertial motions of a coupled system constituted by a rigid body containing a viscous compressible fluid. We then provide a weak-strong uniqueness result that allows…

Analysis of PDEs · Mathematics 2020-03-18 Giovanni Paolo Galdi , Václav Mácha , Šárka Nečasová

We derive and study two different formalisms used for non-equilibrium processes: The coherent-state path integral, and an effective, coarse-grained stochastic equation of motion. We first study the coherent-state path integral and the…

Statistical Mechanics · Physics 2016-04-20 Kay Jörg Wiese

We develop a mathematically rigorous path integral representation of the time evolution operator for a model of (1+1) quantum gravity that incorporates factor ordering ambiguity. In obtaining a suitable integral kernel for the…

Mathematical Physics · Physics 2017-06-08 John Haga , Rachel Lash Maitra

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

Weak measurements performed between quantum state preparation and post-selection result in complex values for self-adjoint operators, corresponding to complex conditional probabilities for the projections on specific eigenstates. In this…

Quantum Physics · Physics 2011-10-14 Holger F. Hofmann

The present paper is a short review of different path integral representations of the partition function of quantum spin systems. To begin with, I consider coherent states for SU(2) algebra. Different parameterizations of the coherent…

Strongly Correlated Electrons · Physics 2012-11-20 Naoum Karchev

We generalize the concept of a weak value of a quantum observable to cover arbitrary real positive operator measures. We show that the definition is operationally meaningful in the sense that it can be understood within the quantum theory…

Quantum Physics · Physics 2013-05-29 Erkka Haapasalo , Pekka Lahti , Jussi Schultz

The quantization of systems with first- and second-class constraints within the coherent-state path-integral approach is extended to quantum systems with fermionic degrees of freedom. As in the bosonic case the importance of path-integral…

Quantum Physics · Physics 2011-09-13 Georg Junker , John R. Klauder

Weakly chaotic or weakly interacting systems have a wide regime where the common random matrix theory modeling does not apply. As an example we consider cold atoms in a nearly integrable optical billiard with displaceable wall ("piston").…

Quantum Physics · Physics 2011-07-08 Alexander Stotland , Louis M. Pecora , Doron Cohen

This paper establishes a natural quantum counterpart of weak equilibration for statistical ensembles in integrable systems. For quantum systems with pure point spectrum, single-time expectation values under unitary evolution are typically…

Dynamical Systems · Mathematics 2026-03-26 Xinyu Liu

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