When you buy high and sell low it's really hard to generate returns, even if you do it with great enthusiasm and great volume.

当你高价买入低价卖出时,是很难产生回报的,不管你有多大交易热情或有多大交易量

耶鲁公开课 - 金融市场课程节选

Let's say we start from some V1 and p1 here, so high pressure, small volume and we end up with a high volume low pressure, under constant temperature condition.

例如我们要从压强比较高，体积比较小V1，p1出发,到达低压强，大体积的末态，过程中温度不变。

麻省理工公开课 - 热力学与动力学课程节选