Meaning of entropy (what is it, concept and definition)

What is Entropy:

As entropy is known the natural tendency to lose order in a system. The word, as such, comes from the Greek ἐντροπία (entropy), which literally means 'back', although today it is used in various figurative senses.

The term entropy was initially coined by the German physicist Rudolf Clausius when he observed that, in any irreversible process, a small amount of thermal energy always went outside the system boundary. Since then, the term has been used in the most varied disciplines of knowledge, such as physics, chemistry, mathematics, astrophysics, linguistics, computing or ecology, to refer to the measure of disorder that build a system.

Thus, for example, in Physics, entropy refers to the degree of irreversibility that, in a thermodynamic system, is achieved after a process that involves the transformation of energy. In Chemistry, on the other hand, it refers to the entropy observed in the formation of a chemical compound. In Astrophysics, it alludes to the entropy observed in black holes. In information theories, entropy is the degree of uncertainty in relation to a data set. While, in Computing, it refers to the randomness collected by an operating system or an application for its use in cryptography.

Entropy in thermodynamics

In the area of ​​thermodynamics, entropy is known as the physical quantity that measures the part of the energy that cannot be used to carry out work and, consequently, is lost. Thus, in an isolated system, a small amount of energy will always be dissipated outside the system. This value, as such, always tends to grow in the course of a naturally occurring process. In this sense, entropy describes the irreversibility of thermodynamic systems. For example, when you put an ice cube in a glass of water at room temperature, after a few minutes, the cube will go into a liquid state, as its temperature will increase, while the water will cool, until both reach thermal equilibrium. This is because the universe tends to distribute energy evenly, that is, to maximize entropy.

Negative entropy

As negative entropy, or neguentropy, it is called the entropy that a system exports to keep its entropy low. Thus, to compensate for the degradation process to which, over time, every system is subject, some open systems manage to conserve their natural entropy thanks to the contributions of the other subsystems with which they are related. Thus, in the open system, negative entropy supposes a resistance that is sustained in the associated subsystems that allow it to rebalance the entropic system, unlike the closed system, in which the entropic process cannot stop by itself.