Observational Constraints on the f(R) Theory of Modified Gravity

我們利用宇宙學以及局部尺度的實驗去制約f(R) 設計者模型(designer f(R) models)。對於宇宙學尺度的制約，我們發現，儘管可以產生任何期望的宇宙膨脹，然而為了要符合大尺度結構實驗的制約，f(R)設計者遭受到微調問題 (fine-tuning problem)。對於局部重力的制約，目前為止，我們找到了通過局部重力測試的f(R)設計者模型；但是對於這些模型，甚至考慮宇宙學以及局部尺度也無法將它們從宇宙常數模型(ΛCDM model)分辨出來。對於其它在這篇碩士論文所考慮的有效狀態方程，我們未找到可通過局部重力測試的f(R)設計者模型。In this thesis we constrain the designer f(R) models by the observations in both cosmological and local scales. For the cosmological observation constraints, we find that although the designer f(R) can generate any desired cosmic expansion his-tory, it suffers from the fine-tuning problem in order to fit the large scale structure constraints well. For local gravity constraints, so far we do search out the viable designer f(R) models that can satisfy the local gravity constraints but would be indistinguishable from the ΛCDM model even considering the observations in both cosmological and local scales and for other effective equation of states we consider in this thesis, we do not find out any viable designer f(R) model