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arXiv 1101.2177astro-ph.COgr-qchep-th
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暗能量和基本常数随时间变化的另一种观点

A Different Look at Dark Energy and the Time Variation of Fundamental Constants

Marvin Weinstein

摘要:

本文做了一个简单的观察,一个基本长度,或截断,在弗里德曼-勒梅特-罗伯逊-沃克(FRW)宇宙学的背景下,意味着非常不同的东西比一个静态的宇宙。有人认为,这是合理的假设,这种截止是通过固定的数量的量子自由度每共同运动的体积(而不是普朗克体积)和宇宙学常数(或暗能量)的理论中的所有领域的真空能量的关系进行重新检查。需要满足的一般理论,以避免与目前的实验冲突的限制进行了讨论,它表明,在任何理论满足这些限制知道$w$和负一之间的差异允许一个预测$\dot{w}$。有人认为,这是一个强大的结果,如果这一预测失败的想法正在讨论的类型的基本截止可以排除。最后,据观察,在一个特定的理论的背景下,一个共同移动的截止意味着一个可预测的基本常数的时间变化。这是伴随着一个一般性的讨论,为什么会这样,什么是最强的现象学限制在这个预测的变化,以及限制是在紧张的想法,一个共同移动的截止。然而,它指出,仔细比较预测的基本常数的时间变化是不可能的,而不限于一个特定的模型场理论,这是没有在本文中完成。

英文摘要:

This paper makes the simple observation that a fundamental length, or cutoff, in the context of Friedmann-Lemaître-Robertson-Walker (FRW) cosmology implies very different things than for a static universe. It is argued that it is reasonable to assume that this cutoff is implemented by fixing the number of quantum degrees of freedom per co-moving volume (as opposed to a Planck volume) and the relationship of the vacuum-energy of all of the fields in the theory to the cosmological constant (or dark energy) is re-examined. The restrictions that need to be satisfied by a generic theory to avoid conflicts with current experiments are discussed, and it is shown that in any theory satisfying these constraints knowing the difference between $w$ and minus one allows one to predict $\dot{w}$. It is argued that this is a robust result and if this prediction fails the idea of a fundamental cutoff of the type being discussed can be ruled out. Finally, it is observed that, within the context of a specific theory, a co-moving cutoff implies a predictable time variation of fundamental constants. This is accompanied by a general discussion of why this is so, what are the strongest phenomenological limits upon this predicted variation, and which limits are in tension with the idea of a co-moving cutoff. It is pointed out, however, that a careful comparison of the predicted time variation of fundamental constants is not possible without restricting to a particular model field-theory and that is not done in this paper.

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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