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Starting with a mathematical boundary value problem for the magnetic vector potential in an axisymmetric cylindrical coordinate system, we derive a general solution for any arbitrary current distribution using the method of Green's…

Astrophysics of Galaxies · Physics 2015-06-15 Bartek Ewertowski , Shantanu Basu

We construct an explicit Green's function for the conjugated Laplacian $e^{-\omega \cdot x/h}\Delta e^{-\omega \cdot x/h}$, which let us control our solutions on roughly half of the boundary. We apply the Green's function to solve a partial…

Analysis of PDEs · Mathematics 2016-10-07 Francis J. Chung , Leo Tzou

We propose topological Hochschild homology as a tool for measuring ramification of maps of structured ring spectra. We determine second order topological Hochschild homology of the $p$-local integers. For the tamely ramified extension of…

Algebraic Topology · Mathematics 2020-08-12 Bjørn Ian Dundas , Ayelet Lindenstrauss , Birgit Richter

We present a theoretical analysis of the approximation properties of convolutional architectures when applied to the modeling of temporal sequences. Specifically, we prove an approximation rate estimate (Jackson-type result) and an inverse…

Machine Learning · Computer Science 2023-05-31 Haotian Jiang , Qianxiao Li

In this paper, we introduce and develop the concept of \emph{ramification} in a given modulus. We study some properties in relation to this concept and it's connection to some important problems in mathematics, particularly the Goldbach…

Number Theory · Mathematics 2026-03-10 Theophilus Agama

Dzhaparidze and Spreij [5] showed that the quadratic variation of a semimartingale can be approximated using a randomized periodogram. We show that the same approximation is valid for a special class of continuous stochastic processes. This…

Probability · Mathematics 2012-03-07 Ehsan Azmoodeh , Esko Valkeila

In these notes, we begin by recalling aspects of the classical theory of metric Diophantine approximation; such as theorems of Khintchine, Jarn\'{\i}k, Duffin-Schaeffer and Gallagher. We then describe recent strengthening of various…

Number Theory · Mathematics 2016-01-11 Victor Beresnevich , Felipe Ramírez , Sanju Velani

We give concentration bounds for martingales that are uniform over finite times and extend classical Hoeffding and Bernstein inequalities. We also demonstrate our concentration bounds to be optimal with a matching anti-concentration…

Probability · Mathematics 2015-12-03 Akshay Balsubramani

Elaboration of some fundamental relations in three dimensional quantum mechanics is considered taking into account the restricted character of areas in radial distance. In such cases the boundary behavior of the radial wave function and…

Quantum Physics · Physics 2019-12-12 Anzor Khelashvili , Teimuraz Nadareishvili

In this paper, we investigate whether Variational Principles can be associated with the Helmholtz equation subject to impedance (absorbing) boundary conditions. This model has been extensively studied in the literature from both…

Numerical Analysis · Mathematics 2025-11-18 G. Makrakis , C. Makridakis , D. Mitsoudis , M. Plexousakis , T. Pryer

A factorization theory is proposed for Wiener-Hopf plus Hankel operators with almost periodic Fourier symbols. We introduce a factorization concept for the almost periodic Fourier symbols such that the properties of the factors will allow…

Functional Analysis · Mathematics 2007-05-23 A. P. Nolasco , L. P. Castro

Every conformal field theory has the symmetry of taking each field to its adjoint. We consider here the quotient (orbifold) conformal field theory obtained by twisting with respect to this symmetry. A general method for computing such…

High Energy Physics - Theory · Physics 2013-11-01 Doron Gepner , Herve Partouche

We observe two kinds of fractal approximating graphs, the background structures of the generalized Sierpinski Arrowhead Curve independently of the recursive curves. Both graphs related to the generalized Sierpinski Gasket and based on a…

Combinatorics · Mathematics 2017-10-27 András Kaszanyitzky

We study the equations of conformal gravity, as given by Mannheim, in the weak field limit, so that a linear approximation is adequate. Specializing to static fields with spherical symmetry, we obtain a second-order equation for one of the…

General Relativity and Quantum Cosmology · Physics 2018-11-15 Peter R. Phillips

We introduce the fractional magnetic operator involving a magnetic potential and an electric potential. We formulate an inverse problem for the fractional magnetic operator. We determine the electric potential from the exterior partial…

Analysis of PDEs · Mathematics 2020-07-13 Li Li

The problem of recovering acoustic sources, more specifically monopoles, from point-wise measurements of the corresponding acoustic pressure at a limited number of frequencies is addressed. To this purpose, a family of sparse optimization…

Optimization and Control · Mathematics 2021-03-30 Konstantin Pieper , Bao Quoc Tang , Philip Trautmann , Daniel Walter

We derive an exact, time-dependent analytical magnetic field solution for the inner heliosheath, which satisfies both the induction equation of ideal magnetohydrodynamics in the limit of infinite electric conductivity and the magnetic…

Solar and Stellar Astrophysics · Physics 2022-12-28 Christian Röken , Jens Kleimann , Horst Fichtner

In arXiv:2011.06562, the first author and Otto van Koert proved a generalized version of the classical Poincar\'e-Birkhoff theorem, for Liouville domains of any dimension. In this article, we prove a relative version for Lagrangians with…

Symplectic Geometry · Mathematics 2025-01-10 Agustin Moreno , Arthur Limoge

Electrostatic Green functions for grounded equipotential circular and elliptical rings, and grounded hyperspheres in n-dimension electrostatics, are constructed using Sommerfeld's method. These electrostatic systems are treated…

Classical Physics · Physics 2019-05-02 Hassan Alshal

A central qubit coupled to an Ising ring of $N$ qubits, operating close to a critical point is investigated as a potential precision quantum magnetometer for estimating an applied transverse magnetic field. We compute the Quantum Fisher…

Quantum Physics · Physics 2018-05-09 Noufal Jaseem , S. Omkar , Anil Shaji