# The Second Law and Entropy Misconceptions Demystified

## Abstract

**:**

## 1. Introduction

## 2. The Essence of “Mass-Energy, Entropy and the Second Law Fundamentals”

**Box 1.**Natural Processes and Laws.

**Box 2.**It Is Hard to Believe Nowadays.

## 3. The Three Essential “Entropy and Second Law Misconceptions”

#### 3.1. Is Entropy a Measure of Any Disorder?

**Box 3.**Entropy Is Thermal Randomness, Not Any Randomness.

#### 3.2. Can the Second Law Be Valid and Entropy Always Increasing in Isolated Systems and the Universe, but (Maybe) Not Necessarily in All Processes and All Space and Time Scales?

**Box 4.**Entropy Is Always Generated at Any Space and Time Scales and Cannot Be Destroyed by Any Means.

#### 3.3. Can Self-Sustained Non-equilibrium, i.e., Structural Quasi-Equilibrium, Violates the Second Law?

**Box 5.**A Quasi-Equilibrium with Non-Uniform Properties Does Not Violate the Second Law.

## 4. Other Typical “Entropy and Second Law Misconceptions”

#### 4.1. Does Maxwell’s Demon Violate the Second Law?

**Box 6.**Maxwell’s Demon Requires More Effort Than Just to Operate a Gate [15].

#### 4.2. Can a Vortex Tube and Similar Cooling Devices Violate the Second Law?

#### 4.3. Could the Second Law Be Violated during Animated Life and Intelligent Processes?

**Box 7.**Creation of Ordered Structures or Live Species Always Generate Thermal Disorder, i.e., Always Generate Entropy.

#### 4.4. Could the Second Law Be Violated during Micro-Fluctuations?

**Box 8.**Near-Reversible Micro-Fluctuations Make Up Macro-Equilibrium and Cannot Be Demonized to Destroy Entropy.

#### 4.5. Could the Second Law Be Violated Locally and Temporarily and “Compensated” Elsewhere Later?

**Box 9.**Entropy Cannot Be Destroyed, Locally or at a Time, and “Compensated” by Generation Elsewhere or Later.

#### 4.6. Thermodynamic “Arrow of Time”

**Box 10.**The “Thermodynamic Arrow of Time” May Be the Answer to “Where Does Our Arrow of Time Come From?”

## 5. Further Comments

**Box 11.**Hypotheses of Second Law Violation Are Still to Be Proven.

## Funding

## Conflicts of Interest

## References and Note

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**MDPI and ACS Style**

Kostic, M.M.
The Second Law and Entropy Misconceptions Demystified. *Entropy* **2020**, *22*, 648.
https://doi.org/10.3390/e22060648

**AMA Style**

Kostic MM.
The Second Law and Entropy Misconceptions Demystified. *Entropy*. 2020; 22(6):648.
https://doi.org/10.3390/e22060648

**Chicago/Turabian Style**

Kostic, Milivoje M.
2020. "The Second Law and Entropy Misconceptions Demystified" *Entropy* 22, no. 6: 648.
https://doi.org/10.3390/e22060648