English
Related papers

Related papers: The Response Field and the Saddle Points of Quantu…

200 papers

We introduce configuration space path integrals for quantum fields interacting with classical fields. We show that this can be done consistently by proving that the dynamics are completely positive directly, without resorting to master…

General Relativity and Quantum Cosmology · Physics 2025-07-23 Jonathan Oppenheim , Zachary Weller-Davies

Nowadays the term 'sign problem' is used to identify two different problems. The ideas to overcome the first type of the 'sign problem' of strongly oscillating complex valued imtegrand in the Feynman path integrals comes from…

Statistical Mechanics · Physics 2020-03-04 Vladimir Filinov , Alexander Larkin

We reformulate time evolution of systems in mixed states in terms of the classical observables of correlators using the Weyl correspondence rule. The resulting equation of motion for the Wigner functional of the density matrix is found to…

High Energy Physics - Theory · Physics 2007-05-23 Herbert Nachbagauer

The main difficulty for path integral Monte Carlo studies of Fermi systems results from the requirement of antisymmetrization of the density matrix and is known in literature as the 'sign problem'. To overcome this issue the new numerical…

Plasma Physics · Physics 2017-05-09 Alexander Larkin , Vladimir Filinov , Vladimir Fortov

A path integral approach to quantum physics has been developed. Fractional path integrals over the paths of the L\'evy flights are defined. It is shown that if the fractality of the Brownian trajectories leads to standard quantum and…

Mathematical Physics · Physics 2009-11-13 Nick Laskin

We construct a representation of the coherent state path integral using the Weyl symbol of the Hamiltonian operator. This representation is very different from the usual path integral forms suggested by Klauder and Skagerstan in…

Quantum Physics · Physics 2009-11-13 L. C. dos Santos , M. A. M. de Aguiar

Path integrals developed by Richard Feynman have been an important tool in Physics in studying quantum field theory. In mathematics, it has also been widely used in providing formal proofs in the study of Index theorem and asymptotic…

Probability · Mathematics 2017-02-23 Zhehua Li

The relation of the Wigner function with the fair probability distribution called tomographic distribution or quantum tomogram associated with the quantum state is reviewed. The connection of the tomographic picture of quantum mechanics…

Quantum Physics · Physics 2015-06-19 Margarita A. Man'ko , Vladimir I. Man'ko

Coherent state functional integrals for the minisuperspace models of quantum cosmology are studied. By the well-established canonical theories, the transition amplitudes in the path-integral representations of Wheeler-DeWitt quantum…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Li Qin , Yongge Ma

This discussion examines recent developments in the theory of a Weyl-like, Cartan geometry with natural Schr\"odinger field behavior proposed previously. In that model, very nearly exactly a coupled Einstein-Maxwell- Schr\"odinger,…

General Relativity and Quantum Cosmology · Physics 2008-02-03 J. E. Rankin

We explore whether quantum field theory can be understood as the statistical mechanics of a time-reversal-invariant stochastic generalization of Hamiltonian dynamics. The motivation for this project, started with this paper, is to assign…

Quantum Physics · Physics 2026-03-24 Simon Friederich , Mritunjay Tyagi

These lectures are intended as an introduction to the technique of path integrals and their applications in physics. The audience is mainly first-year graduate students, and it is assumed that the reader has a good foundation in quantum…

Quantum Physics · Physics 2007-05-23 Richard MacKenzie

I assume a universe whereby the speed of light and the planck constant are not constants but instead parameters that vary locally in time-and space. When describing motion, I am able to derive a modified path integral description at the…

General Physics · Physics 2008-02-18 Roee Amit

A description of scalar charged particles, based on the Feshbach-Villars formalism, is proposed. Particles are described by an object that is a Wigner function in usual coordinates and momenta and a density matrix in the charge variable. It…

Quantum Physics · Physics 2009-11-07 B. I. Lev , A. A. Semenov , C. V. Usenko

Coherent state functional integral for the minisuperspace model of loop quantum cosmology is studied. By the well-established canonical theory, the transition amplitude in the path integral representation of loop quantum cosmology with…

General Relativity and Quantum Cosmology · Physics 2012-06-07 Li Qin , Yongge Ma

We present an analysis of the Feynman path centroid density that provides new insight into the correspondence between the path integral and the Schr\"odinger formulations of statistical mechanics. The path centroid density is a central…

Statistical Mechanics · Physics 2009-10-31 Rafael Ramírez , Telesforo López-Ciudad

The book deals with a stochastic formulation of path integration in real time, by rotating the_space_ variables over exp(i pi/4). Preliminary chapters deal with quantum and classical mechanics, probability theory and stochastic calculus,…

Quantum Physics · Physics 2007-05-23 Alec Maassen van den Brink

The formulation of noncommutative quantum mechanics as a quantum system represented in the space of Hilbert-Schmidt operators is used to systematically derive, using the standard time slicing procedure, the path integral action for a…

High Energy Physics - Theory · Physics 2014-02-11 Sunandan Gangopadhyay , Frederik G Scholtz

Factorization of the (formal) path integral measure in a Wiener path integrals for Yang--Mills diffusion is studied. Using the nonlinear filtering stochastic differential equation, we perform the transformation of the path integral defined…

High Energy Physics - Theory · Physics 2007-11-20 S. N. Storchak

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