The relation of empty cellar radiation energy density and absolute temperature is derived through Thermody- namics and Statistical Physics two methods, the ones that thus state Thermodynamics and Statistical Physics are unified.

• 用热力学与统计物理学两种方法推导了空窖辐射的辐射能量密度与绝对温度的关系；通过推导过程阐释了热力学与统计物理学的统一.