论文标题
关于弱重力镜头对宇宙膨胀功能的敏感性
On the sensitivity of weak gravitational lensing to the cosmic expansion function
论文作者
论文摘要
我们分析了宇宙剪切功率谱的功能衍生物$ c_ \ ell^γ$相对于宇宙膨胀函数。我们对这样做的兴趣是两个方面：（i）鉴于试图检测宇宙扩张函数的微小变化，这可能是由于可能与时间相关的黑暗能量密度引起的，我们希望知道弱透镜功率谱对扩展功能的变化敏感。 （ii）鉴于距离测量值的宇宙扩展函数的最新经验确定，与特定的宇宙学模型无关，我们希望找出扩展功能中的不确定性如何转化为宇宙剪切功率谱中的不确定性。我们找到以下答案：扩展功能的相对变化通过宇宙剪切功率频谱$ \ \ 2-6 $放大，这取决于应用更改的比例因子，以及一个示例的当前不确定性扩展函数的当前不确定性可易于流行$ \ y \ y \ \最大的$ \ y \ \％$。
We analyse the functional derivative of the cosmic-shear power spectrum $C_\ell^γ$ with respect to the cosmic expansion function. Our interest in doing so is two-fold: (i) In view of attempts to detect minor changes of the cosmic expansion function which may be due to a possibly time-dependent dark-energy density, we wish to know how sensitive the weak-lensing power spectrum is to changes in the expansion function. (ii) In view of recent empirical determinations of the cosmic expansion function from distance measurements, independent of specific cosmological models, we wish to find out how uncertainties in the expansion function translate to uncertainties in the cosmic-shear power spectrum. We find the following answers: Relative changes of the expansion function are amplified by the cosmic-shear power spectrum by a factor $\approx 2-6$, weakly depending on the scale factor where the change is applied, and the current uncertainty of one example for an empirically determined expansion function translates to a relative uncertainty of the cosmic-shear power spectrum of $\approx10\,\%$.
