'Why does meat get cooked faster in a pressure cooker? or What's the Concept of pressure cooking?

Pressure cooker is an airtight container that initially doesn't leak the air out below the preset pressure.As volume is always fixed(constant) inside,the Temperature will increase proportionally to the pressure inside(Gay-Los sac's Law).Now the pressure built inside effects rising the Liquid's Temp higher before reaching Liquid's boiling point.This higher boiling point of the liquids help the stuffs(meat) to cook faster.