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Related papers: Inverse problem in Parker's dynamo

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A rigorous Bayesian formulation of the inverse doping profile problem in infinite dimensions for a stationary linearized unipolar drift-diffusion model for semiconductor devices is given. The goal is to estimate the posterior probability…

Numerical Analysis · Mathematics 2024-08-22 Leila Taghizadeh , Ansgar Jüngel

We pose and solve an inverse problem for the classical field equations that arise in the Standard Model of particle physics. Our main result describes natural conditions on the representations, so that it is possible to recover all the…

Analysis of PDEs · Mathematics 2025-06-02 Xi Chen , Matti Lassas , Lauri Oksanen , Gabriel P. Paternain

We develop the technique of inverse Mellin transform for processes occurring in a background magnetic field. We show by analyticity that the energy (momentum) derivatives of a field theory amplitude at the zero energy (momentum) is equal to…

High Energy Physics - Phenomenology · Physics 2009-11-07 Guey-Lin Lin

We consider the problem of estimating rare event probabilities, focusing on systems whose evolution is governed by differential equations with uncertain input parameters. If the system dynamics is expensive to compute, standard sampling…

Computation · Statistics 2019-11-05 Siddhant Wahal , George Biros

The Monte Carlo method in the canonical ensemble is used to investigate magnetization reversal in amorphous transition metal - rare earth multilayers. Our study is based on a model containing diluted clusters which exhibit an effective…

Materials Science · Physics 2009-12-01 Etienne Talbot , Denis Ledue , Pierre Emmanuel Berche

Two different approaches to the Roberts dynamo problem are considered. Firstly, the equations governing the magnetic field are specified to both harmonic and subharmonic solutions and reduced to matrix eigenvalue problems, which are solved…

Fluid Dynamics · Physics 2009-05-07 F. Plunian , K. -H. Radler

Typical geophysical inversion problems are ill-posed, non-linear and non-unique. Sometimes the problem is trans-dimensional, where the number of unknown parameters is one of the unknowns, which makes the inverse problem even more…

Geophysics · Physics 2010-02-25 Xiaolin Luo

We present results from four convectively-driven stellar dynamo simulations in spherical wedge geometry. All of these simulations produce cyclic and migrating mean magnetic fields. Through detailed comparisons we show that the migration…

Solar and Stellar Astrophysics · Physics 2014-12-01 Jörn Warnecke , Petri J. Käpylä , Maarit J. Käpylä , Axel Brandenburg

The diffusion quantum Monte Carlo method is extended to solve the old theoretical physics problem of many-electron atoms and ions in intense magnetic fields. The feature of our approach is the use of adiabatic approximation wave functions…

Quantum Physics · Physics 2009-11-13 S. Bucheler , D. Engel , J. Main , G. Wunner

The computer processing of images of magnetic force microscopy of cobalt nanodots was performed. The solution of reverse task of magnetic force microscopy is obtained for surface points of samples. Superposition of fields, which are…

Computational Physics · Physics 2017-01-10 Konstantin Nefedev , Vitalii Kapitan , Yuriy Shevchenko

The eigenvalues and eigenfunctions of a linear {\alpha}^{2}-dynamo have been computed for different spatial distributions of an isotropic \alpha-effect. Oscillatory solutions are obtained when \alpha exhibits a sign change in the radial…

Earth and Planetary Astrophysics · Physics 2012-08-08 A. Giesecke , F. Stefani , G. Gerbeth

Slender magnetic elements provide a versatile platform for programmable shape-morphing under remote magnetic actuation. However, a general and physically interpretable framework for the inverse design of a `magneto-elastica' under…

Soft Condensed Matter · Physics 2026-04-15 JiaHao Li , Yingchao Zhang , Weicheng Huang , Shenghao Ye , HengAn Wu , Dominic Vella , Mingchao Liu

Modeling physical phenomena like heat transport and diffusion is crucially dependent on the numerical solution of partial differential equations (PDEs). A PDE solver finds the solution given coefficients and a boundary condition, whereas an…

Graphics · Computer Science 2022-08-04 Ekrem Fatih Yılmazer , Delio Vicini , Wenzel Jakob

Properties of space-like monopoles projected on the 3D space in finite temperature quenched SU(2) QCD are studied. The monopole energy is derived from the effective action of the monopoles which is determined by an inverse Monte-Carlo…

High Energy Physics - Lattice · Physics 2009-11-10 Tsuneo Suzuki , M. N. Chernodub , Katsuya Ishiguro

We calculate the number density, energy density, transverse pressure, longitudinal pressure, and magnetization of an ensemble of spin one-half particles in the presence of a homogenous background magnetic field. The magnetic field direction…

Nuclear Theory · Physics 2013-05-27 Michael Strickland , Veronica Dexheimer , Debora P. Menezes

The asymmetric time dependence and various statistical properties of polarity reversals of the Earth's magnetic field are utilized to infer some of the most essential parameters of the geodynamo, among them the effective (turbulent)…

Geophysics · Physics 2009-05-15 Michael Fischer , Gunter Gerbeth , Andre Giesecke , Frank Stefani

The homogeneous dynamo effect is at the root of cosmic magnetic field generation. With only a very few exceptions, the numerical treatment of homogeneous dynamos is carried out in the framework of the differential equation approach. The…

Astrophysics · Physics 2009-11-10 Mingtian Xu , Frank Stefani , Gunter Gerbeth

Diagrammatic Monte Carlo approach is applied to a problem of a single spin-down fermion resonantly interacting with the sea of ideal spin-up fermions. On one hand, we develop a generic, sign-problem tolerant, method of exact numerical…

Statistical Mechanics · Physics 2009-11-13 Nikolay Prokof'ev , Boris Svistunov

The dynamo effect is the most popular candidate to explain the non-primordial magnetic fields of astrophysical objects. Although many systematic studies of parameters have already been made to determine the different dynamical regimes…

Fluid Dynamics · Physics 2020-07-14 Mélissa D. Menu , Ludovic Petitdemange , Sébastien Galtier

Monte Carlo is famous for accepting model extensions and model refinements up to infinite dimension. However, this powerful incremental design is based on a premise which has severely limited its application so far: a state-variable can…