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arXiv 1604.08039gr-qc
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Brans-Dicke理论框架下物质不守恒引起的宇宙膨胀研究

A Study of Cosmic Expansion Generated by Non-conservation of Matter in the Framework of Brans-Dicke Theory

Sudipto Roy, Mohsin Islam

摘要:

在Brans-Dicke理论的框架下,通过物质与标量场的相互作用,物质与暗能量相互转化的可能性是目前宇宙膨胀研究的基础。利用标量场参数对标度因子的经验依赖性,求解了空间平坦时空的场方程。为了表示关于物质不守恒的行为,一个函数,用哈勃参数表示,已被经验性地纳入场方程。他们的解表明,这个函数的值与宇宙的物质含量成正比,随时间单调递减。这种物质场的相互作用产生了后期的加速度,导致减速参数从正变为负。宇宙中暗能量分量的比例随时间的变化已被确定并以图形表示。本文分析了引力常量和Brans-Dicke无量纲参数随时间的变化。物质产生暗能量的速率影响减速参数和引力常量的时间变化。

英文摘要:

The present study, on the expansion of universe, is based on an assumption regarding the possibility of inter-conversion between matter and dark energy, through some interaction of matter with the scalar field in the framework of Brans-Dicke theory. The field equations for a spatially flat space-time have been solved using an empirical dependence of scalar field parameter upon the scale factor. To represent the behaviour regarding the non-conservation of matter, a function, expressed in terms of the Hubble parameter, has been empirically incorporated into the field equations. Their solution shows that, this function, whose value is proportional to the matter content of the universe, decreases monotonically with time. This matter-field interaction generates late time acceleration, causing the deceleration parameter to change its sign from positive to negative. Time dependence of the proportion of dark energy component of the universe has been determined and shown graphically. Time variation of gravitational constant and the Brans-Dicke dimensionless parameter has been analyzed in the present study. The rate of generation of dark energy from matter has been found to affect the time variations of deceleration parameter and gravitational constant.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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