What happens to entropy as a system approaches absolute zero?

As a system approaches absolute zero, entropy reaches its minimum value. This concept is rooted in the third law of thermodynamics, which states that as the temperature of a perfect crystal approaches absolute zero, the entropy of the system approaches a constant minimum.

At absolute zero, the motion of particles theoretically comes to a halt, and the system reaches a state of perfect order with only one microstate possible for the crystalline structure. Since entropy is a measure of the number of microstates or the degree of disorder in a system, at absolute zero, the lack of disorder means that the entropy is minimized.

This behavior is significant because it highlights the unique relationship between temperature and entropy, especially in the context of low-temperature physics and thermodynamic processes. Understanding this principle is essential for interpreting various physical phenomena and the behavior of materials as they cool down towards absolute zero.