标题： 轴子物理的台球类比 显示英文标题

标题： The Pooltable Analogy to Axion Physics

摘要： 一个名为TSP的想象角色发现自己在一个地板倾斜的游乐室里。 然而，游乐室里的台球桌是水平的。 TSP想知道这是怎么做到的。 在思考这个问题的过程中，他踏上了一段智力旅程，这段旅程与过去二十年来对强$CP$问题和轴子物理感兴趣的物理学家所经历的旅程相呼应。 显示英文摘要

摘要： An imaginary character named TSP finds himself in a playroom whose floor is tilted to one side. However, the pooltable in the playroom is horizontal. TSP wonders how this can be. In doing so, he embarks upon an intellectual journey which parallels that which has been travelled during the past two decades by physicists interested in the Strong $CP$ Problem and axion physics.