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Related papers: The He atom revisited

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Quantum computers promise to efficiently solve important problems that are intractable on a conventional computer. For quantum systems, where the dimension of the problem space grows exponentially, finding the eigenvalues of certain…

Applicability of Feynman path integral approach to numerical simulations of quantum dynamics in real time domain is examined. Coherent quantum dynamics is demonstrated with one dimensional test cases (quantum dot models) and performance of…

Computational Physics · Physics 2023-07-19 Ilkka Ruokosenmäki , Tapio T. Rantala

In this paper, we build Wiener measure for the path space on the Heisenberg group by using of the heat kernel corresponding to the sub-Laplacian and give the definition of the Wiener integral. Then we give the Feynman-Kac formula.

Functional Analysis · Mathematics 2016-11-26 Heping Liu , Yingzhan Wang

Feynman path integrals provide an elegant, classically inspired representation for the quantum propagator and the quantum dynamics, through summing over a huge manifold of all possible paths. From computational and simulational…

Quantum Physics · Physics 2022-06-22 Yanming Che , Clemens Gneiting , Franco Nori

We achieve a quantum speed-up of fully polynomial randomized approximation schemes (FPRAS) for estimating partition functions that combine simulated annealing with the Monte-Carlo Markov Chain method and use non-adaptive cooling schedules.…

Quantum Physics · Physics 2013-06-12 Pawel Wocjan , Chen-Fu Chiang , Anura Abeyesinghe , Daniel Nagaj

Based on the Sum-over-Paths approach of Richard Feynman, an integration method for calculating wave phase vectors is derived. The diffraction and interference patterns of various slit masks can be calculated from such phase vectors. The…

Computational Physics · Physics 2022-08-19 Josef Joerg

We follow the Feynman procedure to obtain a path integral formulation of loop quantum cosmology starting from the Hilbert space framework. Quantum geometry effects modify the weight associated with each path so that the effective measure on…

General Relativity and Quantum Cosmology · Physics 2011-01-25 Abhay Ashtekar , Miguel Campiglia , Adam Henderson

We present a method for solving the reaction-diffusion equation with general potential in free space. It is based on the approximation of the Feynman-Kac formula by a sequence of convolutions on sequentially diminishing grids. For…

Numerical Analysis · Mathematics 2015-11-17 M. S. Litsarev , I. V. Oseledets

The kinetic energy is estimated for the ground-state of liquid $^3$He at equilibrium density. The obtained value for this quantity, $10.16\pm0.05$ K/atom at density $0.0163~\mbox{\AA}$, is in agreement with most of the experimental data…

Quantum Gases · Physics 2019-01-30 V. Zampronio , S. A. Vitiello

Experiments at the interface of quantum field theory and general relativity would greatly benefit theoretical research towards their unification. The gravitational aspects of quantum experiments performed so far can be explained either…

General Relativity and Quantum Cosmology · Physics 2025-09-25 Thomas B. Mieling , Christopher Hilweg , Philip Walther

In this paper, a complete covariant quantization of generalized electrodynamics is shown through the path integral approach. To this goal, we first studied the hamiltonian structure of system following Dirac's methodology and, then, we…

High Energy Physics - Theory · Physics 2011-02-18 Rodrigo Bufalo , Bruto Max Pimentel , German Enrique Ramos Zambrano

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

Subspace diagonalisation methods have appeared recently as promising means to access the ground state and some excited states of molecular Hamiltonians by classically diagonalising small matrices, whose elements can be efficiently obtained…

Quantum Physics · Physics 2024-03-13 Maria-Andreea Filip , David Muñoz Ramo , Nathan Fitzpatrick

We perform a thorough analysis of the relationship between discrete and series representation path integral methods, which are the main numerical techniques used in connection with the Feynman-Kac formula. First, a new interpretation of the…

Statistical Mechanics · Physics 2009-11-07 Cristian Predescu , J. D. Doll

We present a method using Feynman-like diagrams to calculate the statistical properties of random many-body potentials. This method provides a promising alternative to existing techniques typically applied to this class of problems, such as…

Other Condensed Matter · Physics 2015-06-23 Rupert Small , Sebastian Müller

The method of geometric quantization is applied to a particle moving on an arbitrary Riemannian manifold $Q$ in an external gauge field, that is a connection on a principal $H$-bundle $N$ over $Q$. The phase space of the particle is a…

High Energy Physics - Theory · Physics 2015-06-26 M. A. Robson

Feynman proposed a postulate or a method of quantization in his celebrated paper in 1948. Applying Feynman's postulate to temporally continuous quantum measurements of the positions of particles, Mensky proposed the restricted Feynman path…

Mathematical Physics · Physics 2023-11-27 Wataru Ichinose

We explicitly connect (discrete-time) quantum walks on Z with a four-state Markov additive process via a Feynman-type formula (2.5). Using this representation, we derive a relation between the spectral decomposition of the Markov additive…

Probability · Mathematics 2025-10-16 Jean-Pierre Fouque , Tomoyuki Ichiba , Ka Lok Lam

We describe a quantum algorithm based on an interior point method for solving a linear program with $n$ inequality constraints on $d$ variables. The algorithm explicitly returns a feasible solution that is $\varepsilon$-close to optimal,…

Quantum Physics · Physics 2026-02-02 Simon Apers , Sander Gribling

Path integral implementation of the quantum instanton approximation currently belongs among the most accurate methods for computing quantum rate constants and kinetic isotope effects, but its use has been limited due to the rather high…

Chemical Physics · Physics 2017-05-10 Konstantin Karandashev , Jiri Vanicek