Second law of thermodynamics

The Second Law of Thermodynamics formalizes the observation that energy in a closed system tends to become less useful over time, a concept also known as entropy. This principle is fundamental in predicting the direction of natural processes and understanding the limits of energy conversion and work.
 Rudolf Clausius Germany 1850 Second law of thermodynamics

The Second Law of Thermodynamics formalizes the observation that energy in a closed system tends to become less useful over time, a concept also known as entropy. This principle is fundamental in predicting the direction of natural processes and understanding the limits of energy conversion and work.