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We construct supersymmetric conformal sigma models in three dimensions. Nonlinear sigma models in three dimensions are nonrenormalizable in perturbation theory. We use the Wilsonian renormalization group equation method, which is one of the…

High Energy Physics - Theory · Physics 2007-10-26 Takeshi Higashi , Kiyoshi Higashijima , Etsuko Itou

The use of adaptive mesh refinement (AMR) techniques is crucial for accurate and efficient simulation of higher dimensional spacetimes. In this work we develop an adaptive algorithm tailored to the integration of finite difference…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Frans Pretorius , Luis Lehner

We study the superspace formulation of the noncommutative nonlinear supersymmetric O(N) invariant sigma-model in 2+1 dimensions. We prove that the model is renormalizable to all orders of 1/N and explicitly verify that the model is…

High Energy Physics - Theory · Physics 2009-11-07 H. O. Girotti , M. Gomes , A. Yu. Petrov , V. O. Rivelles , A. J. da Silva

This paper analyzes the nonlinear correspondence between the reflectivity profile (model) and the plane wave impulse response at the boundary (data) for a three-dimensional half space consisting of a sequence of homogeneous horizontal…

Mathematical Physics · Physics 2012-06-14 Peter C. Gibson

We present a covariant model of a spherically symmetric black hole with corrections motivated by loop quantum gravity. The effective modifications, parametrized by a positive constant $\lambda$, are implemented through a canonical…

General Relativity and Quantum Cosmology · Physics 2022-10-07 Asier Alonso-Bardaji , David Brizuela , Raül Vera

A primary spectral submanifold (SSM) is the unique smoothest nonlinear continuation of a nonresonant spectral subspace $E$ of a dynamical system linearized at a fixed point. Passing from the full nonlinear dynamics to the flow on an…

Dynamical Systems · Mathematics 2023-06-28 George Haller , Bálint Kaszás , Aihui Liu , Joar Axås

The nonlinear Schr\"{o}dinger equation (NLSE) is one of the most important equations in quantum mechanics, and appears in a wide range of applications including optical fibre communications, plasma physics and biomolecule dynamics. It is a…

Numerical Analysis · Mathematics 2019-07-05 J. A. Mackenzie , W. R. Mekwi

The $U_L(3)\times U_R(3)$ Linear Sigma Model (LSM) with quark degrees of freedom is used to show that radiative corrections generate undetermined finite contributions. Their origin is related to surface terms which are differences between…

High Energy Physics - Phenomenology · Physics 2007-05-23 Brigitte Hiller , A. L. Mota , M. C. Nemes , Alexander A. Osipov , Marcos Sampaio

We consider a one-dimensional singularly perturbed 4th order problem with the additional feature of a shift term. An expansion into a smooth term, boundary layers and an inner layer yields a formal solution decomposition, and together with…

Numerical Analysis · Mathematics 2023-09-22 Sebastian Franz , Kleio Liotati

Observing the list of compatible second order equations of Absolute Parallelism (AP) found by Einstein and Mayer (they used D=4), we choose the one-parameter class of equations which take on a 3-linear form (when contra-frame density of…

General Relativity and Quantum Cosmology · Physics 2022-09-08 I. L. Zhogin

In this paper we propose a novel metric learning framework called Nullspace Kernel Maximum Margin Metric Learning (NK3ML) which efficiently addresses the small sample size (SSS) problem inherent in person re-identification and offers a…

Computer Vision and Pattern Recognition · Computer Science 2018-07-31 T M Feroz Ali , Subhasis Chaudhuri

The Minimal Supersymmetric Standard Model (MSSM) can include two soft breaking terms which are often neglected: a non-analytic scalar trilinear coupling and a Higgsino bilinear term. A set of high-scale boundary conditions consistent with…

High Energy Physics - Phenomenology · Physics 2010-02-03 J. P. J. Hetherington

An intrinsic curvature model is investigated using the canonical Monte Carlo simulations on dynamically triangulated spherical surfaces of size upto N=4842 with two fixed-vertices separated by the distance 2L. We found a first-order…

Statistical Mechanics · Physics 2009-11-11 S. Obata , M. Egashira , T. Endo , H. Koibuchi

The nonlinear sigma model (NLSM) epitomises a field-theoretical approach to (interacting) electrons in disordered media. These lectures are aimed at the audience who might have vaguely heard about its existence but know very little of what…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Igor V. Lerner

In this work, we introduce the novel application of the adaptive mesh refinement (AMR) technique in the global stability analysis of incompressible flows. The design of an accurate mesh for transitional flows is crucial. Indeed, an…

Numerical Analysis · Mathematics 2026-02-17 Daniele Massaro , Valerio Lupi , Adam Peplinski , Philipp Schlatter

We propose a new self-adaptive, double-loop smoothing algorithm to solve composite, nonsmooth, and constrained convex optimization problems. Our algorithm is based on Nesterov's smoothing technique via general Bregman distance functions. It…

Optimization and Control · Mathematics 2018-08-15 Quoc Tran-Dinh , Ahmet Alacaoglu , Olivier Fercoq , Volkan Cevher

Regression with a spherical response is challenging due to the absence of linear structure, making standard regression models inadequate. Existing methods, mainly parametric, lack the flexibility to capture the complex relationship induced…

Methodology · Statistics 2025-04-01 Houren Hong , Janice L. Scealy , Andrew T. A. Wood , Yanrong Yang

This paper presents a new computer code to solve the general relativistic magnetohydrodynamics (GRMHD) equations using distributed parallel adaptive mesh refinement (AMR). The fluid equations are solved using a finite difference Convex ENO…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Matthew Anderson , Eric Hirschmann , Steven L. Liebling , David Neilsen

We present a novel solution procedure for initial boundary value problems. The procedure is based on an action principle, in which coordinate maps are included as dynamical degrees of freedom. This reparametrization invariant action is…

Numerical Analysis · Mathematics 2024-12-31 Alexander Rothkopf , W. A. Horowitz , Jan Nordström

We derive spherically symmetric solutions of the classical \lambda-R model, a minimal, anisotropic modification of general relativity with a preferred foliation and two local degrees of freedom. Starting from a 3 + 1 decomposition of the…

General Relativity and Quantum Cosmology · Physics 2017-08-30 Renate Loll , Luis Pires