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This paper presents an algorithmic framework for solving unconstrained stochastic optimization problems using only stochastic function evaluations. We employ central finite-difference based gradient estimation methods to approximate the…

Optimization and Control · Mathematics 2025-01-14 Raghu Bollapragada , Cem Karamanli

$p$-Adic divergence and gradient operators are constructed giving rise to $p$-adic vertex Laplacian operators used by Z\'u\~niga in order to study Turing patterns on graphs, as well as their edge Laplacian counterparts. It is shown that the…

Analysis of PDEs · Mathematics 2024-06-21 Patrick Erik Bradley

The geometric, electronic and magnetic properties of strained graphene nanoribbons were investigated using spin polarized calculations within the framework of density functional theory. Cases of compressive stress along the longer axis of a…

Mesoscale and Nanoscale Physics · Physics 2020-06-10 Sandeep Kaur , Hitesh Sharma , V. K. Jindal , Vladimir Bubanja , Isha Mudahar

Laser-controlled entanglement between atomic qubits (`spins') and collective motion in trapped ion Coulomb crystals requires conditional momentum transfer from the laser. Since the spin-dependent force is derived from a spatial gradient in…

Atomic Physics · Physics 2021-12-06 Adam D West , Randall Putnam , Wesley C Campbell , Paul Hamilton

We numerically investigate the electronic transport properties between two mesoscopic graphene disks with a twist by employing the density functional theory coupled with non-equilibrium Green's function technique. By attaching two graphene…

Mesoscale and Nanoscale Physics · Physics 2020-07-01 Yulei Han , Yafei Ren , Xinlong Dong , Junjie Zeng , Wei Ren , Zhenhua Qiao

We study the formulation of bond-orientational order in an arbitrary two dimensional geometry. We find that bond-orientational order is properly formulated within the framework of differential geometry with torsion. The torsion reflects the…

Statistical Mechanics · Physics 2009-10-31 Mark Bowick , Alex Travesset

The N\'eel order of an antiferromagnet subject to a spin torque can undergo precession in a circular orbit about any chosen axis. To orient and stabilize the motion against the effects of magnetic anisotropy, the spin polarization should…

Applied Physics · Physics 2021-02-03 Arun Parthasarathy , Egecan Cogulu , Andrew D. Kent , Shaloo Rakheja

Second-order methods, which utilize gradients as well as Hessians to optimize a given function, are of major importance in mathematical optimization. In this work, we prove tight bounds on the oracle complexity of such methods for smooth…

Optimization and Control · Mathematics 2017-08-18 Yossi Arjevani , Ohad Shamir , Ron Shiff

In this preliminary study, we provide two methods for estimating the gradients of functions of real value. Both methods are built on derivative estimations that are calculated using the standard method or the Squire-Trapp method for any…

Numerical Analysis · Mathematics 2023-12-04 Ergun Akleman , Alan Freed

Motivated by recent experimental results that reveal rich collective dynamics of thousands-to-millions of active liquid crystal skyrmions we have developed a coarse grained particle-based model of the dynamics of skyrmions in dilute regime.…

Soft Condensed Matter · Physics 2023-05-08 Allison W. Teixeira , Mykola Tasinkevych , Cristóvão S. Dias

We present a completely gauge-invariant operator definition of transverse-momentum-dependent parton densities (TMD), supplied with longitudinal lightlike gauge links as well as transverse gauge links at lightcone infinity. Within this…

High Energy Physics - Phenomenology · Physics 2011-11-30 I. O. Cherednikov , N. G. Stefanis

We prove functional limit theorems for lattice point counting for affine and congruence lattices using the method of moments. Our main tools are higher moment formulae for Siegel transforms on the corresponding homogeneous spaces, which we…

Number Theory · Mathematics 2024-11-20 Mahbub Alam , Anish Ghosh , Jiyoung Han

A data structure for finite bounded acyclic categories has been built, which is useful to encode and manipulate abstract orientable incidence structure. It can be represented as a directed acyclic multigraph with weighted edges, where the…

Data Structures and Algorithms · Computer Science 2023-07-04 Yu-Wei Huang

We derive the gluon transverse-momentum-dependent (TMD) operator structure of back-to-back quark-antiquark dijet production in deep inelastic scattering at arbitrary Bjorken-x to twist-3 accuracy. Working at leading order in the strong…

High Energy Physics - Phenomenology · Physics 2026-02-18 Swagato Mukherjee , Vladimir V. Skokov , Andrey Tarasov , Shaswat Tiwari , Fei Yao

We study theoretically the interaction of twisted light with graphene. The light-matter interaction matrix elements between the tight-binding states of electrons in graphene are determined near the Dirac points. We examine the dynamics of…

Mesoscale and Nanoscale Physics · Physics 2015-06-17 M. B. Farías , G. F. Quinteiro , P. I. Tamborenea

Terahertz spintronics offers the prospect of devices which are both faster and more energy-efficient. A promising route to achieve this goal is to exploit current-induced spin-orbit torques. However, the high-frequency properties of these…

Mesoscale and Nanoscale Physics · Physics 2020-12-21 Filipe S. M. Guimarães , Juba Bouaziz , Manuel dos Santos Dias , Samir Lounis

A thorough discussion and development of the calculus of real-valued functions of complex-valued vectors is given using the framework of the Wirtinger Calculus. The presented material is suitable for exposition in an introductory Electrical…

Optimization and Control · Mathematics 2009-06-29 Ken Kreutz-Delgado

This article starts with the mathematical definition, concrete description, and physical meaning of Cartan's torsion. I proceed with the argumentation that torsion is required for the description of intrinsic spin. Moreover I argue that the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Rainer W. Kuhne

Illumination of a two-dimensional system by a twisted light beam is considered in order to find specific effects caused by twisting. Direct interband transitions between the valence and conduction bands are supposed. The generation rates of…

Mesoscale and Nanoscale Physics · Physics 2023-01-18 L. S. Braginsky , M. M. Mahmoodian , L. I. Magarill , M. V. Entin

We establish tightness of graph-based stochastic processes in the space $D[0+\epsilon,1-\epsilon]$ with $\epsilon >0$ that allows for discontinuities of the first kind. The graph-based stochastic processes are based on statistics…

Probability · Mathematics 2023-03-02 Lynna Chu , Hao Chen