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arXiv 1004.2014gr-qcastro-ph.EP
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关于f(R)引力的1/c展开

On the 1/c Expansion of f(R) Gravity

Joachim Näf, Philippe Jetzer

摘要:

我们推导出应用于孤立系统-太阳系的规模-第一相对论性条款的$1/c$扩展的时空度规$g_{μν}$的度量$f(R)$重力理论,其中$f$被假定为解析在$R=0$。为了我们的目的,它足以考虑到二次项的$f(R)$的扩展,因此,我们可以近似$f(R) = R + aR^2$与一个积极的维参数$a$。在非相对论极限下,我们得到了一个附加的Yukawa修正,该修正是由耦合强度$G/3$和康普顿波长$\sqrt{6a}$对牛顿势的修正,这是文献中已知的结果.作为应用,我们导出了引力场中陀螺仪的大地岁差改正和双星的岁差改正的同阶。重力探测器B的实验结果给出了极限$a \lesssim 5 \times 10^{11} \, \mathrm{m}^2$,而对于PSR J 0737 -3039系统中的脉冲星B,我们得到的极限大约是它的$10^4$倍。另一方面,Eöt-Wash实验提供了最佳的实验室结合$a \lesssim 10^{-10} \, \mathrm{m}^2$。虽然测地岁差的前界比实验室的大得多,但在存在某种类型的变色龙效应的情况下,它们仍然是有意义的,因此在不同的长度尺度上,有效值可能是不同的。

英文摘要:

We derive for applications to isolated systems - on the scale of the Solar System - the first relativistic terms in the $1/c$ expansion of the space time metric $g_{μν}$ for metric $f(R)$ gravity theories, where $f$ is assumed to be analytic at $R=0$. For our purpose it suffices to take into account up to quadratic terms in the expansion of $f(R)$, thus we can approximate $f(R) = R + aR^2$ with a positive dimensional parameter $a$. In the non-relativistic limit, we get an additional Yukawa correction with coupling strength $G/3$ and Compton wave length $\sqrt{6a}$ to the Newtonian potential, which is a known result in the literature. As an application, we derive to the same order the correction to the geodetic precession of a gyroscope in a gravitational field and the precession of binary pulsars. The result of the Gravity Probe B experiment yields the limit $a \lesssim 5 \times 10^{11} \, \mathrm{m}^2$, whereas for the pulsar B in the PSR J0737-3039 system we get a bound which is about $10^4$ times larger. On the other hand the Eöt-Wash experiment provides the best laboratory bound $a \lesssim 10^{-10} \, \mathrm{m}^2$. Although the former bounds from geodesic precession are much larger than the laboratory ones, they are still meaningful in the case some type of chameleon effect is present and thus the effective values could be different at different length scales.

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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