Science

The Particle Theory係話: partical(粒子)係組成所有物質gei基本單位
Brownian motion係話: 細微gei煙灰粒移動的軌跡係'之'字型因為佢地俾更加細微gei空氣粒子不斷撞擊.

'The Particle Theory':
The particle theory says that all matter consists of many, very small particles which are constantly moving or in a continual state of motion. The degree to which the particles move is determined by the amount of energy they have and their relationship to other particles. The particles might be atoms, molecules or ions.

'Brownian motion' :
The term Brownian motion (in honor of the botanist Robert Brown) refers to either
The physical phenomenon that minute particles immersed in a fluid move about randomly; or
The mathematical models used to describe those random movements.
The mathematical model can also be used to describe many phenomena not resembling (other than mathematically) the random movements of minute particles. An often quoted example is stock market fluctuations. Another example is the evolution of physical characteristics in the fossil record.