arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1709.01360gr-qchep-th
收藏

约旦和爱因斯坦框架中的哈勃图

Hubble Diagrams in the Jordan and Einstein Frames

Reza Rashidi

摘要:

不同的宇宙学模型通常预测不同的哈勃图。然后,哈勃图之间的比较可以用作区分不同宇宙学场景的一种方式。但情况并非总是如此,因为不能保证两个不同的模型总是有不同的哈勃图。两个物理上不等价的模型可能有相同的哈勃图。在这种情况下,哈勃图不能用来区分两个模型,必须找到另一种方法来区分它们。因此,使用哈勃图是否可以区分两种不同的场景是一个重要的问题,这个问题没有明显的答案。引力的$f(R)$理论的约旦框架和爱因斯坦框架是不等价的,只要度量性条件在两个框架中都成立。在本文中,它是认为,如果考虑到爱因斯坦框架中的粒子质量的时间变化,实际上从Ia型超新星巡天导出的哈勃图并不能使我们区分这两个框架。然而,我们表明,通过等待足够长的时间来测量哈勃图的变化,有可能区分两个帧。换句话说,哈勃图不能单独用来区分两个帧,但哈勃图中变化率之间的比较可以提供一种方法。

英文摘要:

Different models in cosmology generally predict different Hubble diagrams. Then, the comparison between the Hubble diagrams may be used as a way for distinguishing between different cosmological scenarios. But that is not always the case because there is no guarantee that two different models always have different Hubble diagrams. It may be possible for two physically-inequivalent models to have the same Hubble diagrams. In that case, the Hubble diagram cannot be used to differentiate between two models and it is necessary to find another way to distinguish between them. Therefore, the question of whether two different scenarios are distinguishable by using the Hubble diagrams is an important question which would not have an obvious answer. The Jordan and Einstein frames of $f(R)$ theories of gravity are inequivalent, provided that the metricity condition holds in both frames. In the present paper it is argued that if the time-variation of particle masses in the Einstein frame is taken into consideration, the Hubble diagram derived practically from type Ia supernova surveys does not enable us to differentiate between these two frames. Nevertheless, we show that by waiting long enough to measure the change in Hubble diagram it is possible to differentiate between two frames. In other words, the Hubble diagram cannot be employed alone to differentiate between two frames but comparison between the rates of changes in Hubble diagrams can provide a way to do so.

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。

↑