According to the prevailing view, once the IGM had cooled from its hot, ionized state to a colder mixture of neutral hydrogen and helium, it offered no effective resistance to gravity.

• 一般的观点认为：IGM一旦从它那炽热、游离的状态冷却成温度较低的中性氢和氦的混合物，它将无法有效对抗重力。