Think of color, pitch, loudness, heaviness, and hotness. Each is the topic of a branch of physics.

Think of color, pitch, loudness, heaviness, and hotness. Each is the topic of a branch of physics.

想想颜色、音高、响度、重量和热度。每一个都是物理学一个分支的主题。

-- Benoit Mandelbrot 曼德勃罗