本文首先敘述在二十世紀時宇宙學上重大發現，並以佛立德曼模
型為基礎，討論宇宙在不同ｋ值時，宇宙總密度W與減速度參數q 的特性。同時探討宇宙常數L 不為零時，如何從宇宙動力學方程式中得到可能的宇宙模型。接著說明如何從放射性元素的衰變、球狀星團中恆星的演化和白矮星的冷卻等測量方法得到宇宙年齡的下限，並使用最新的觀測資料來得出目前宇宙年齡的下限。之後介紹目前宇宙加速膨脹的觀測證據與現今宇宙參數的最新數值，並且利用不同宇宙模型來探討宇宙年齡的計算方法，將所得的結果與實際的觀測資料相互做比較。最後則提到兩個實驗－SNAP 與Planck 對未來宇宙學的重要性與影響。

This thesis starts with the important discoveries of cosmology at 20th century and discusses the universe total density W and decelerating parameter q at different curvature k on the Friedman Model. By using qualitative analysis of the universal dynamic equations, we discuss the possible cosmological models with cosmological constant L . Beside using the three methods, the decay of heavy elements, the evolution of stars in the globular clusters, and the cooling of white dwarf , to get the lower limit age
of the universe, we also use the latest observational data to get the lower limit of the universe. Then we describe the latest parameters of the universe in the present epoch and the evidences of the accelerating universe. According to the different cosmological models, we adapt the latest parameters to get the age of universe and compare the results with the observational data. Finally, it describes the two important experiments, SNAP and Planck, that will make the cosmology more accurate and precise in the future.

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