The second law of thermodynamics

The second law of thermodynamics states that the entropy in a closed system can only increase and never decrease.

The formal definition of the second law of thermodynamics is Clausius inequality that states that in equilibrium the entropy’s expression has a maximum value. Moreover, the entropy in the universe tends to increase and will never be decreased. A common misconception is that entropy is a measure of disorder (whatever disorder means). Therefore some people believe that evolution violates the second law. Nevertheless, entropy is a measure of uncertainty that is sometimes related  to disorder and sometimes to complexity. When entropy increases complexity increases and order is formed. Similarly there is another misconception that was originated by Boltzmann, Helmholtz and lord Kelvin that the second law will bring the world to “heat death“, namely thermal equilibrium in which no energy will flow. This is with contradiction to our observation that complex structures are constantly formed. In his book entropy, philosopher Jeremy Rifkin applies this approach  to economy, arguing that economy will eventually destroy itself. This prediction is also with contradiction to our observation that the economy is constantly growing and improving. Our book explains the influence of entropy on economy in a more “optimistic” way, namely, increasing uncertainty and therefore increasing opportunities.

Others claim that the second law is a probabilistic law, therefore there is a very small (practically zero) probability of entropy decrease and therefore violating the second law of thermodynamics. Nevertheless, entropy is related only to the number of possible configurations and has no connection to the “order” of a one specific configuration or another. Therefore, the second law cannot be violated.