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相关论文: Direction Dependence of the Deceleration Parameter

200 篇论文

We revisit the evolution of cosmic acceleration in a spatially flat $w_0w_a$CDM universe, in which the equation of state of dark energy takes the CPL parametrization, using the latest baryon acoustic oscillation (BAO) measurements from the…

宇宙学与河外天体物理 · 物理学 2025-08-12 Jincheng Wang , Hongwei Yu , Puxun Wu

We introduce directional regularity, a new definition of anisotropy for multivariate functional data. Instead of taking the conventional view, which determines anisotropy as a notion of smoothness along a dimension, directional regularity…

统计方法学 · 统计学 2026-05-05 Omar Kassi , Sunny G. W. Wang

Cosmic acceleration is investigated through a kink-like expression for the deceleration parameter (q). The new parametrization depends on the initial (q_i) and final (q_f) values of q, on the redshift of the transition from deceleration to…

天体物理学 · 物理学 2009-06-23 Emille E. O. Ishida , Ribamar R. R. Reis , Alan V. Toribio , Ioav Waga

Some anisotropy in both mechanical and thermodynamical properties of bismuth is expected. A combination of density functional theory total energy calculations and density functional perturbation theory in the local density approximation is…

材料科学 · 物理学 2016-04-20 B. Arnaud , S. Lebègue , G. Raffy

Experiments on tetragonal Sr2RuO4 and CeIrIn5 indicate the presence of superconductivity with a multi-component superconducting order parameter. Such an order parameter should exhibit an in-plane anisotropy in the upper critical field near…

超导电性 · 物理学 2009-11-07 D. F. Agterberg

We study Anderson localization of a scalar wave in an ensemble of resonant point scatterers embedded in an anisotropic background medium. For uniaxial anisotropy of moderate strength, the mobility edges and the critical exponent of the…

无序系统与神经网络 · 物理学 2021-07-27 Antton Goïcoechea , John H. Page , Sergey E. Skipetrov

In this paper, we derive the non-commutative corrections to the maximal acceleration of a massive particle. Using the eight-dimensional kappa-deformed phase-space metric, we obtain the kappa-deformed maximal acceleration, valid up to first…

高能物理 - 理论 · 物理学 2020-12-23 E. Harikumar , Vishnu Rajagopal

The rates governing momentum broadening in a quark-gluon plasma with a momentum anisotropy are calculated to leading-log order for a heavy quark using kinetic theory. It is shown how the problematic singularity for these rates at…

高能物理 - 唯象学 · 物理学 2008-11-26 Paul Romatschke

This study explores a distinctive logarithmic parameterization of the deceleration parameter within the $f(Q, C)$ gravity framework, incorporating a nonlinear functional form $f(Q, C) = \gamma_1 Q^n + \gamma_2 C$, where $Q$ and $C$ denote…

广义相对论与量子宇宙学 · 物理学 2025-06-03 S. R. Bhoyar , Yash B. Ingole

We report the finding of a scaling relation among the cosmic-web anisotropy parameter $A$, the linear density rms fluctuation sigma(r) and the linear growth factor D(z). Using the tidal field derived from the Millennium Simulation on…

宇宙学与河外天体物理 · 物理学 2010-11-29 Jounghun Lee , Volker Springel

We examine the optical conductivity in antiferromagnetic (AFM) iron pnictides by mean-field calculation in a five-band Hubbard model. The calculated spectra are well consistent with the in-plane anisotropy observed in the measurements,…

超导电性 · 物理学 2015-03-17 K. Sugimoto , E. Kaneshita , T. Tohyama

We use quadratic maximum-likelihood (QML) estimators to constrain models with Gaussian but statistically anisotropic Cosmic Microwave Background (CMB) fluctuations, using CMB maps with realistic sky-coverage and instrumental noise. This…

宇宙学与河外天体物理 · 物理学 2012-03-06 Duncan Hanson , Antony Lewis

The purpose of this research is to study the upper critical field (Hc2) of two-band superconductors by two-band Ginzburg - Landau approach. The analytical formula of Hc2 included anisotropy of order parameter and anisotropy of…

超导电性 · 物理学 2009-11-11 P. Udomsamuthirun , A. Changjan , C. Kumvongsa , S. Yoksan

We revisit constraints on the (pseudo)conformal Universe from the non-observation of statistical anisotropy in the Planck data. The quadratic maximal likelihood estimator is applied to the Planck temperature maps at frequencies 143 GHz and…

宇宙学与河外天体物理 · 物理学 2015-03-05 G. I. Rubtsov , S. R. Ramazanov

The resistivity anisotropy unveiled in the study of detwinned single crystals of the undoped 122 pnictides is here studied using the two-dimensional three-orbital Hubbard model in the mean-field approximation. Calculating the Drude weight…

超导电性 · 物理学 2015-05-30 Xiaotian Zhang , Elbio Dagotto

Regularized estimation of quantitative ultrasound (QUS) parameters, such as attenuation and backscatter coefficients, has gained research interest. Recently, the alternating direction method of multipliers (ADMM) has been applied…

信号处理 · 电气工程与系统科学 2026-01-29 Ali K. Z. Tehrani , Hassan Rivaz , Ivan M. Rosado-Mendez

The expansion of the universe may be observed in ``realtime'' by measuring changes in the patterns of the anisotropy in the CMB. As the universe ages, the surface of decoupling--or the CMB photosphere--moves away from us and samples a…

天体物理学 · 物理学 2009-11-13 S. Lange , L. Page

Conditions for a maximum or minimum of Poisson's ratio of anisotropic elastic materials are derived. For a uniaxial stress in the 1-direction and Poisson's ratio $\nu$ defined by the contraction in the 2-direction, the following three…

材料科学 · 物理学 2007-05-23 Andrew N. Norris

Numerical solutions to hyperbolic partial differential equations, involving wave propagations in one direction, are subject to several specific errors, such as numerical dispersion, dissipation or aliasing. In multi-dimensions, where the…

数值分析 · 数学 2019-02-13 Adrian Sescu

The evolution of the dark energy parameter within the scope of a spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with perfect fluid and dark energy components is studied by generalizing the recent results…

综合物理 · 物理学 2014-03-11 Anirudh Pradhan