论文标题
带有ELT和SKAO测量的红移漂移宇宙学
Redshift drift cosmography with ELT and SKAO measurements
论文作者
论文摘要
绘制宇宙的扩展历史是物理宇宙学的一项令人信服的任务,尤其是在宇宙最近加速的观察证据的背景下,这表明宇宙学和粒子物理学的规范理论是不完整的,并且仍有新的物理学。宇宙学是一种现象学方法的宇宙学方法,其中(一些需要注意的)物理数量在宇宙红移$ z $中作为泰勒系列扩展,或类似的参数,例如续订的红移$ y = z/(1+z)$或GoolegarithMic redShiftMic redShift $ x = \ x = \ ln {(1+z)} $。此外,宇宙学扩展之后物体的红移漂移提供了一个独立于模型的可观察的,可通过目前正在建设的设施检测到{\ it。在这里,我们使用来自两个设施的模拟红移漂移测量值来评估宇宙学影响和模型区分红移漂移宇宙学的功能。 We find that the combination of measurements from the two facilities can provide a stringent test of the $Λ$CDM paradigm, and that overall the logarithmic based expansions of the spectroscopic velocity drift are the most reliable ones, performing better than analogous expansions in the redshift or the rescaled redshift: the former nominally gives the smaller error bars for the cosmographic coefficients but is vulnerable to biases in高阶术语(换句话说,它仅在低红移时是可靠的),而后者的性能总是很差。
Mapping the expansion history of the universe is a compelling task of physical cosmology, especially in the context of the observational evidence for the recent acceleration of the universe, which demonstrates that canonical theories of cosmology and particle physics are incomplete and that there is new physics still to be discovered. Cosmography is a phenomenological approach to cosmology, where (with some caveats) physical quantities are expanded as a Taylor series in the cosmological redshift $z$, or analogous parameters such as the rescaled redshift $y=z/(1+z)$ or the logarithmic redshift $x=\ln{(1+z)}$. Moreover, the redshift drift of objects following cosmological expansion provides a model-independent observable, detectable by facilities currently under construction, {\it viz.} the Extremely Large Telescope and the Square Kilometre Array Observatory (at least in its full configuration). Here we use simulated redshift drift measurements from the two facilities to carry out an assessment of the cosmological impact and model discriminating power of redshift drift cosmography. We find that the combination of measurements from the two facilities can provide a stringent test of the $Λ$CDM paradigm, and that overall the logarithmic based expansions of the spectroscopic velocity drift are the most reliable ones, performing better than analogous expansions in the redshift or the rescaled redshift: the former nominally gives the smaller error bars for the cosmographic coefficients but is vulnerable to biases in the higher order terms (in other words, it is only reliable at low redshifts), while the latter always performs poorly.