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Complex processes ranging from protein folding to nuclear fission often follow a low-dimension reaction path parameterized in terms of a few collective variables. In nuclear theory, variables related to the shape of the nuclear density in a…

We develop fully noncommutative Feynman-Kac formulae by employing quantum stochastic processes. To this end we establish some theory for perturbing quantum stochastic flows on von Neumann algebras by multiplier cocycles. Multiplier cocycles…

Functional Analysis · Mathematics 2018-01-18 Alexander C. R. Belton , J. Martin Lindsay , Adam G. Skalski

Feynman path integrals formalism for non-relativistic quantum mechanics is revisited. A comparison is made with the cases of light progagation (Huygens principle) and Brownian motion. The difficulties for a physical model behind Feynman…

Quantum Physics · Physics 2025-10-09 Emilio Santos

A very small dispersion in the speed of light may be observable in Fermi time- and energy-tagged data on variable sources, such as gamma-ray bursts (GRB) and active galactic nuclei (AGN). We describe a method to compute the size of this…

Instrumentation and Methods for Astrophysics · Physics 2009-12-22 Jeffrey D. Scargle , Slobodan N. Simić

Over the last decade, ingenuous developments in Monte Carlo methods have enabled the unbiased estimation of adjoint-weighted reactor parameters expressed as bilinear forms, such as kinetics parameters and sensitivity coefficients. A…

Computational Physics · Physics 2024-07-09 Eric Dumonteil , Emma Horton , Andreas E. Kyprianou , Andrea Zola

This article provides a new theory for the analysis of forward and backward particle approximations of Feynman-Kac models. Such formulae are found in a wide variety of applications and their numerical (particle) approximation are required…

Statistics Theory · Mathematics 2014-11-17 Hock Peng Chan , Pierre Del Moral , Ajay Jasra

The classic, two-component, crust-superfluid model of a neutron star can be formulated as a noise-driven, linear dynamical system, in which the angular velocities of the crust and superfluid are tracked using a Kalman filter applied to…

High Energy Astrophysical Phenomena · Physics 2021-07-14 Patrick M. Meyers , Nicholas J. O'Neill , Andrew Melatos , Robin J. Evans

The method of Feynman-Kac perturbation of quantum stochastic processes has a long pedigree, with the theory usually developed within the framework of processes on von Neumann algebras. In this work, the theory of operator spaces is…

Operator Algebras · Mathematics 2024-07-10 Alexander C. R. Belton , Stephen J. Wills

This note is answering an old questioning about the F\'{e}nyes-Nelson stochastic mechanics. The Brownian nature of the quantum fluctuations, which are associated to this mechanics, is deduced from Feynman's interpretation of the Heisenberg…

Quantum Physics · Physics 2007-05-23 Michel Fliess

In a view for a simple model where natural selection at the individual level is confronted to selection effects at the group level, we consider some individual-based models of some large population subdivided into a large number of groups.…

Probability · Mathematics 2023-07-13 Aurélien Velleret

Aim of this note is to analyse branching Brownian motion within the class of models introduced in the recent paper [4] and called chemical diffusion master equations. These models provide a description for the probabilistic evolution of…

Probability · Mathematics 2024-01-23 Alberto Lanconelli , Berk Tan Perçin

The evolution of several physical and biological systems, ranging from neutron transport in multiplying media to epidemics or population dynamics, can be described in terms of branching exponential flights, a stochastic process which…

Statistical Mechanics · Physics 2012-10-10 Andrea Zoia , Eric Dumonteil , Alain Mazzolo , Sameh Mohamed

Modern population genetics studies typically involve genome-wide genotyping of individuals from a diverse network of ancestries. An important, unsolved problem is how to formulate and estimate probabilistic models of observed genotypes that…

Populations and Evolution · Quantitative Biology 2017-01-10 Wei Hao , Minsun Song , John D. Storey

Besides their intrinsic nuclear-structure value, nuclear mass models are essential for astrophysical applications, such as r-process nucleosynthesis and neutron-star structure. To overcome the intrinsic limitations of existing…

Nuclear Theory · Physics 2016-01-25 R. Utama , J. Piekarewicz , H. B. Prosper

Following Feynman's treatment of the non-relativistic polaron problem, similar techniques are used to study relativistic field theories: after integrating out the bosonic degrees of freedom the resulting effective action is formulated in…

High Energy Physics - Theory · Physics 2007-05-23 R. Rosenfelder , C. Alexandrou , A. W. Schreiber

We develop a formalism for particle production in a field theory coupled to a strong time-dependent external source. An example of such a theory is the Color Glass Condensate. We derive a formula, in terms of cut vacuum-vacuum Feynman…

High Energy Physics - Phenomenology · Physics 2008-11-26 F. Gelis , R. Venugopalan

The electromagnetic transition between the almost degenerate 5/2+ and 3/2+ states in Th229 is deemed to be very sensitive to potential changes in the fine structure constant alpha. State of the art Hartree-Fock and Hartree-Fock-Bogoliubov…

Nuclear Theory · Physics 2009-08-18 Elena Litvinova , Hans Feldmeier , Jacek Dobaczewski , Victor Flambaum

In the standard hot big bang model, the expansion of the early universe is given by the Friedmann equation with an energy density dominated by relativistic particles. Since in a variety of models this equation is altered, we introduce…

Astrophysics · Physics 2016-08-16 Eduard Massó , Francesc Rota

There are several assumptions made in a standard $\chi^2$ analysis of data, including the frequent assumption that the likelihood function is well approximated by a multivariate Gaussian distribution. This article briefly reviews the…

Nuclear Theory · Physics 2015-02-09 Andrew W. Steiner

The dynamics of fission has been formulated by generalising the asymptotic expansion of the Fokker-Planck equation in terms of the strength of the fluctuations where the diffusion coefficients depend on the stochastic variables explicitly.…

Nuclear Theory · Physics 2009-11-06 Asish K. Dhara , Sailajananda Bhattacharya , Kewal Krishan