Chapter 20 Anger

The concept of entropy originated from what Earth calls the Second Law of Thermodynamics and what Shenzhou refers to as the Third Law of Sky Burning. It measures the degree of "disorder" within a system. The concept of entropy increase also originates from this theorem. It initially indicated that the inevitable flow of heat from high to low temperatures. Extending this idea, another conclusion can be drawn—in an isolated system, entropy increase is inevitable.

The universe is the largest isolated system, which means, this reveals the ultimate theorem on how the universe will die.

At the cosmos's end, all usable energy will be converted into thermal energy. Consequently, all matter loses its "motion." Basic particles cannot exist, superstrings entirely collapse, time completely disappears, and space ceases to have meaning.

This is referred to as "Thermal Death."