What is the Nernst heat theorem?
The Nernst heat theorem, which I proposed, is a statement about the behavior of entropy at absolute zero. It postulates that the change in entropy for any isothermal process involving a pure crystalline solid approaches zero as the temperature tends towards absolute zero (0 Kelvin). This implies that at absolute zero, the entropy of a perfect crystal is a constant, often taken as zero. This principle is fundamental to the third law of thermodynamics, as it provides a clear and measurable basis for defining absolute entropy and understanding the concept of unattainable zero temperature.
Ask Walther Hermann Nernst the follow-up →