Tilted Bianchi Type VI0 Cosmological Model in Saez and Ballester Scalar Tensor Theory of Gravitation

Tilted Bianchi type VI0 cosmological model is investigated in a new scalar tensor theory of gravitation pro-posed by Saez and Ballester (Physics Letters A 113:467, 1986). Exact solutions to the field equations are derived when the metric potentials are functions of cosmic time only. Some physical and geometrical proper-ties of the solutions are also discussed.

Bianchi Type-I Anisotropic Universe with Metric Potential in Saez-Ballester Theory of Gravitation

Bianchi Type-I cosmological model in the presence of Saez-Ballester theory gravitation is studied. An exact solution of the field equation is given by considering the cosmological model yield a metric potential included with a real number. The relation between the deceleration parameter and Hubble parameter and average scale factor is used in that cosmological model. The effect of the viscosity on the entropy of the universe is utilized by energy momentum tensor with bulk viscous terms in a conservative manner. We obtained a formula for calculating the entropy of the universe in terms of viscosity and used it to compare to the study. Also, various physical and kinematical properties have been discussed.

皮凯蒂、赛斯和祖克曼对不平等研究的贡献——科睿唯安“引文桂冠”经济学奖得主学术贡献评介

皮凯蒂、赛斯和祖克曼凭借对收入和财富分配的研究共同被授予2023年度科睿唯安“引文桂冠”经济学奖,预测他们可能问鼎未来的诺贝尔经济学奖。他们在经济不平等问题上的开创性研究不仅为该领域提供了海量的数据支持和深刻的理论见解,更对相关经济政策的制定产生了重大影响,极大地推进了人们对不平等问题的认识和理解。本文旨在概述皮凯蒂、赛斯和祖克曼的主要研究成就,重点归纳他们在不平等研究方面的主要贡献,包括不平等数据库的建立、不平等的长期演变趋势分析、不平等演变的成因及其影响机制,以及不平等问题的研究方法与应对策略等;同时,也将这些贡献与其他相关研究成果进行对比分析,以明确他们的学术观点和内容,在突出其原创性的同时,讨论其研究的潜在局限性。