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We focus on BPS solutions of the gauged O(3) Sigma model, due to Schroers, and use these ideas to study the geometry of the moduli space. The model has an asymmetry parameter $\tau$ breaking the symmetry of vortices and antivortices on the…

高能物理 - 理论 · 物理学 2021-05-04 Rene Garcia

We extend the Bondi formalism to describe asymptotically-flat spacetimes where the outgoing null geodesic congruence is not hypersurface-orthogonal, i.e. has non-vanishing twist. In the Newman-Penrose formulation, the twist…

广义相对论与量子宇宙学 · 物理学 2026-05-26 Marc Geiller , Pujian Mao , Antoine Vincenti

Three Fermion sumrules for interacting systems are derived at T=0, involving the number expectation $\bar{N}(\mu)$, canonical chemical potentials $\mu(m)$, a logarithmic time derivative of the Greens function $\gamma_{\vec{k} \sigma}$ and…

强关联电子 · 物理学 2026-01-14 B Sriram Shastry

We have developed a public code, Optab, that outputs Rosseland, Planck, and two-temperature Planck mean gas opacity tables for radiation hydrodynamics simulations in astrophysics. The code is developed for modern high-performance computing,…

天体物理仪器与方法 · 物理学 2022-03-14 Shigenobu Hirose , Peter Hauschildt , Takashi Minoshima , Kengo Tomida , Takayoshi Sano

It is shown how certain observations interpreted in the background of the Friedmann model with $\Lambda < 0 = k$ (the $\Lambda$CDM model) can be re-interpreted using the $\Lambda = 0$ Lema\^{\i}tre - Tolman (L-T) model so as to do away with…

广义相对论与量子宇宙学 · 物理学 2014-03-20 Andrzej Krasiński

In the realm of robotics, achieving simultaneous localization and mapping (SLAM) is paramount for autonomous navigation, especially in challenging environments like texture-less structures. This paper proposed a factor-graph-based model…

机器人学 · 计算机科学 2024-07-18 Manh Do Duc , Thanh Nguyen Canh , Minh DoNgoc , Xiem HoangVan

Lidar-based SLAM systems are highly sensitive to adverse conditions such as occlusion, noise, and field-of-view (FoV) degradation, yet existing robustness evaluation methods either lack physical grounding or do not capture sensor-specific…

机器人学 · 计算机科学 2025-12-10 Doumegna Mawuto Koudjo Felix , Xianjia Yu , Zhuo Zou , Tomi Westerlund

COSMICS is a package of fortran programs useful for computing transfer functions and microwave background anisotropy for cosmological models, and for generating gaussian random initial conditions for nonlinear structure formation…

天体物理学 · 物理学 2016-08-30 Edmund Bertschinger

In this paper, we propose a framework of the mutual information-maximizing (MIM) quantized decoding for low-density parity-check (LDPC) codes by using simple mappings and fixed-point additions. Our decoding method is generic in the sense…

信息论 · 计算机科学 2022-02-15 Peng Kang , Kui Cai , Xuan He , Shuangyang Li , Jinhong Yuan

Land-use and land cover (LULC) analysis is critical in remote sensing, with wide-ranging applications across diverse fields such as agriculture, utilities, and urban planning. However, automating LULC map generation using machine learning…

计算机视觉与模式识别 · 计算机科学 2024-12-18 Sparsh Pekhale , Rakshith Sathish , Sathisha Basavaraju , Divya Sharma

Saskatchewan Torus-Modified (STOR-M) is a small tokamak, well known for various fusion related basic experimental studies such as edge turbulent heating, different instabilities, AC (alternating current) tokamak operation, Ohmic H-mode…

等离子体物理 · 物理学 2022-06-20 Masaru Nakajima , Debjyoti Basu , A. V. Melnikov , David McColl , Chijin Xiao

We present a new open-source axisymmetric general relativistic hydrodynamics code Gmunu (General-relativistic multigrid numerical solver) which uses a multigrid method to solve the elliptic metric equations in the conformally flat condition…

广义相对论与量子宇宙学 · 物理学 2020-09-24 Patrick Chi-Kit Cheong , Lap-Ming Lin , Tjonnie Guang-Feng Li

The linear properties of the geodesic acoustic modes (GAM) in tokamaks are investigated by means of the comparison of analytical theory and gyrokinetic numerical simulations. The dependence on the value of the safety factor,…

We obtain the correct hamiltonian which describes the dynamics of classes of asymptotic open Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) spacetimes, which includes Tolman geometries. We calculate the surface term that has to be added to…

广义相对论与量子宇宙学 · 物理学 2009-11-10 Nelson Pinto-Neto , Paulo I. Trajtenberg

In this paper, a finite volume lattice Boltzmann method (FVLBM) based on cell-center unstructured girds is presented and full studied to simulate the incompressible laminar flows, which is simple modified from the cell-vertex unstructured…

计算物理 · 物理学 2018-12-04 Yong Wang , Chengwen Zhong , Jun Cao , Congshan Zhuo

We present a new technique for the numerical simulation of axisymmetric systems. This technique avoids the coordinate singularities which often arise when cylindrical or polar-spherical coordinate finite difference grids are used,…

广义相对论与量子宇宙学 · 物理学 2008-11-26 M. Alcubierre , S. Brandt , B. Bruegmann , D. Holz , E. Seidel , R. Takahashi , J. Thornburg

We present the asymptotic solutions for spacetimes with non-zero cosmological constant $\Lambda$ coupled to Maxwell fields, using the Newman-Penrose formalism. This extends a recent work that dealt with the vacuum Einstein (Newman-Penrose)…

广义相对论与量子宇宙学 · 物理学 2017-04-25 Vee-Liem Saw

The purpose of this paper is threefold: First of all the topological aspects of the Landau Hamiltonian are reviewed in the light (and with the jargon) of theory of topological insulators. In particular it is shown that the Landau…

数学物理 · 物理学 2020-04-22 Giuseppe De Nittis , Kyonori Gomi , Massimo Moscolari

We examine simulations of the formation of domain walls, cosmic strings, and monopoles on a cubic lattice, in which the topological defects are assumed to lie at the zeros of a piecewise constant 1, 2, or 3 component Gaussian random field,…

高能物理 - 唯象学 · 物理学 2016-08-25 Robert J. Scherrer , Alexander Vilenkin

We introduce {\tt JuliBootS}, a package for numerical conformal bootstrap computations coded in {\tt Julia}. The centre-piece of {\tt JuliBootS} is an implementation of Dantzig's simplex method capable of handling arbitrary precision linear…

高能物理 - 理论 · 物理学 2014-12-16 Miguel F. Paulos