Daily Archives: 2023年6月20日

作为以太论者的雷诺

雷诺(Osborne Reynolds)是一个以太论者。

我在很多年前,在豆瓣小站写了一篇《剪切增稠和以太》,讲了雷诺构想了了剪胀性流体(dilatant fluid)的物理本质之后,认为这是以太的假想性质可能基于的物理机制。但是很快就有了Michelson-Morley实验,否定了以太的存在。事实上在光速不变实验之后,雷诺仍然写了一本书,用很坚深的数学去构建以太流体的理论。这些都可以在Wikipedia上查到。

事实上,雷诺作为以太论者的迹相,就在他最为著名的工作——提出雷诺数的论文中,就已经体现。他在文中直接明确“不存在绝对时空”,并由此陈述出了一个特别深刻的见解:

As there is no such thing as absolute space or absolute time recognized in mechanical philosophy, to suppose that the character of motion of fluids in any way depended on absolute size or absolute velocity, would be to suppose such motion without the pale of the laws of motion. If then fluids in their motions are subject to these laws, what appears to be the dependance of the character of the motion on the absolute size of the tube and on the absolute velocity of the immersed body, must in reality be a dependance on the size of the tube as compared with the size of some other object, and on the velocity of the body as compared with some other velocity.

O. Reynolds (1883) Phil. Trans. R. Soc. A 174:935

以太作为一个后来被替代掉的范式或研究纲领,却驱使它曾经的“常规科学家”,以“修建保护带”为初衷,催生出后来仍具有强大生命力的物理观念。