在本篇論文裡，我們先介紹兩個插值定理，分別為 Marcinkiewicz 插值定 理與 Riesz-Thorin 插值定理，這些插值定理可以應用在許多不同的地方。 最後介紹 Lorentz Space 與其 Daul Space，重點則會放在 weak L1 的 Dual Space;In this dissertation we study some topics in the area of Fourier analysis. We first introduce two well-known interpolation theorems, which are called Marcinkiewicz interpolation theorem and Riesz-Thorin interpolation theorem. These results appear in a variety of applications. Finally we introduce the Lorentz spaces and their dual spaces, especially the dual space of weak L1.
