标题： 广义引力理论中宇宙学的局限性 显示英文标题

标题： Limitations of cosmography in extended theories of gravity

摘要： 宇宙学方法，该方法仅依赖于宇宙在大尺度上的均匀性和各向同性，已成为处理越来越多的理论可能性以解释宇宙晚期加速膨胀的重要工具，这些理论从修改引力理论到暗能量替代方案，再到测试宇宙学一致性的Lambda-CDM模型。 尽管其具有普遍性，但我们表明，当试图准确重建引力或物质领域中高阶导数的理论时，这种方法存在一些缺点。 本文将展示这种无能的一些典型例子，解释这些限制，并提出可能的解决方法。 显示英文摘要

摘要： The cosmographic approach, which only relies upon the homogeneity and isotropy of the Universe on large scales, has become an essential tool in dealing with an increasing number of theoretical possibilities for explaining the late-time acceleration of the Universe, ranging from Modified Gravity theories to Dark Energy alternatives passing from testing the cosmological concordance Lambda-CDM model. Despite its generality, we show that this method has a number of shortcomings when trying to adequately reconstruct theories with higher-order derivatives in either the gravitational or the matter sector. Herein some paradigmatic examples of such an inability, explanations of the limitations and prospective cures will be presented.