在這篇論文中，我們主要的目的是要研究硬球波茲
曼方程在靠近穩態附近的解的空間行為，更確切地 說，我們的波茲曼方程的解空間行為是在初值條件是 多項式是遞減和初值沒有 Sobolev regularity 的條件 下得到的。

The main goal of this thesis is to understand the quantitative spatial behavior of the solution to the Boltzmann equation for hard sphere in the closed to equilibrium setting. More precisely, we get the quantitative spatial behavior of the solution to the Boltzmann equation under polynomial spatial decay assumption, but without any Sobolev regularity
assumption on the initial condition.

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