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Non-classical states are of practical interest in quantum computing and quantum metrology. These states can be detected through their Wigner function negativity in some regions. In this paper, we calculate the ground state of the…

Quantum Physics · Physics 2021-02-03 Ramón López-Peña , Sergio Cordero , Eduardo Nahmad-Achar , Octavio Castaños

We consider Feynman's path integral approach to quantum mechanics with a noncommutativity in position and momentum sectors of the phase space. We show that a quantum-mechanical system with this kind of noncommutativity is equivalent to the…

High Energy Physics - Theory · Physics 2007-05-23 Branko Dragovich , Zoran Rakic

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

Motivated by application to quantum physics, anticommuting analogues of Wiener measure and Brownian motion are constructed. The corresponding Ito integrals are defined and the existence and uniqueness of solutions to a class of stochastic…

Quantum Physics · Physics 2009-11-06 Steven Leppard , Alice Rogers

We design a particle interpretation of Feynman-Kac measures on path spaces based on a backward Markovian representation combined with a traditional mean field particle interpretation of the flow of their final time marginals. In contrast to…

Statistics Theory · Mathematics 2009-08-19 Pierre Del Moral , Arnaud Doucet , Sumeetpal S. Singh

In a reasonably self-contained and explicit presentation we illustrate the efficiency of the Feynman-Kac formula for the rigorous derivation of three inequalities of interest in non-relativistic quantum mechanics.

Quantum Physics · Physics 2017-08-23 Hajo Leschke , Rainer Ruder

In this article, we investigate the quantum circuit complexity and entanglement entropy in the recently studied black hole gas framework using the two-mode squeezed states formalism written in arbitrary dimensional spatially flat…

High Energy Physics - Theory · Physics 2021-09-03 Kiran Adhikari , Sayantan Choudhury , Satyaki Chowdhury , K. Shirish , Abinash Swain

A systematic classification of Feynman path integrals in quantum mechanics is presented and a table of solvable path integrals is given which reflects the progress made during the last ten years or so, including, of course, the main…

High Energy Physics - Theory · Physics 2007-05-23 Christian Grosche , Frank Steiner

For distinguishable particles it is well known that Brownian motion and a Feynman-Kac functional can be used to calculate the path integral (for imaginary times) for a general class of scalar potentials. In order to treat identical…

Condensed Matter · Physics 2009-10-28 L. F. Lemmens , F. Brosens , J. T. Devreese

Variational algorithms have received significant attention in recent years due to their potential to solve practical problems using noisy intermediate-scale quantum (NISQ) devices. A fundamental step of these algorithms is the evaluation of…

The problem of finding the ground state energy of a Hamiltonian using a quantum computer is currently solved using either the quantum phase estimation (QPE) or variational quantum eigensolver (VQE) algorithms. For precision $\epsilon$, QPE…

Quantum Physics · Physics 2019-04-16 Daochen Wang , Oscar Higgott , Stephen Brierley

Using the circulant symmetry of a Hamiltonian describing three qubits, we realize the quantum Fourier transform. This symmetry allows us to construct a set of eigenvectors independently on the magnitude of physical parameters involved in…

Quantum Physics · Physics 2023-04-05 Mouhcine Yachi , Radouan Hab-arrih , Ahmed Jellal

Work belongs to the most basic notions in thermodynamics but it is not well understood in quantum systems, especially in open quantum systems. By introducing a novel concept of work functional along individual Feynman path, we invent a new…

Statistical Mechanics · Physics 2018-07-30 Ken Funo , H. T. Quan

Richard Feynman's method of path integrals is based on the fundamental assumption that a system starting at a point A and arriving at a point B takes all possible paths from A to B, with each path contributing its own (complex) probability…

Quantum Physics · Physics 2022-10-06 Masud Mansuripur

The density of states for a particle moving in a random potential with a Gaussian correlator is calculated exactly using the functional integral technique. It is achieved by expressing the functional degrees of freedom in terms of the…

Condensed Matter · Physics 2009-10-22 O. K. Vorov , A. V. Vagov

The path integral is calculated for the statistical sum of the microcanonical ensemble in a generic time-parametrization invariant gravitational model with the Friedman-Robertson-Walker (FRW) metric. This represents the first example of a…

High Energy Physics - Theory · Physics 2011-09-28 A. O. Barvinsky

In order to preserve the leading role of the action principle in formulating all field theories one needs quantum field theory, with the associated BRST symmetry, and Feynman-DeWitt-Faddeev-Popov ghost fields. Such fields result from the…

High Energy Physics - Theory · Physics 2025-07-15 Giampiero Esposito , Tepper L. Gill

The main topic of the paper is represented by the change of basis, in Heun-type equations, from the one of decaying (at two singular points) solutions to that of Floquet solutions. Crucial in the connection relations is the phase acquired…

High Energy Physics - Theory · Physics 2025-08-28 Davide Fioravanti , Marco Rossi

The path integral quantization method is applied to a relativistically covariant version of the Hopfield model, which represents a very interesting mesoscopic framework for the description of the interaction between quantum light and…

High Energy Physics - Theory · Physics 2016-03-23 F. Belgiorno , S. L. Cacciatori , F. Dalla Piazza , M. Doronzo

The Feynman path integral for nonrelativistic quantum electrodynamics is studied mathematically of a standard model in physics, where the electromagnetic potential is assumed to be periodic with respect to a large box and quantized thorough…

Mathematical Physics · Physics 2008-09-25 Wataru Ichinose