Dear Colleagues,

The Second Law of Thermodynamics is a fundamental law of the universe, and its ubiquity can be proven by demonstrating its equivalence across all types of thermodynamic systems. This law dictates the direction of energy transfer, which is always from a higher to a lower potential and is always irreversible. It sets the conditions for transferring mass and energy and, thus, the limitations of such processes. This simplicity of causation drives the inexorable movement of energy toward an equilibrium.

The need to delve further into the Second Law of Thermodynamics is essential. This Special Issue intends to assess certain physical and philosophical concepts, to spark dialogue and thoughtful criticism, including certain recent debates, as well as to gain a deeper understanding of the fundamental principles of the Second Law of Thermodynamics.

The Second Law of Thermodynamics is a significant and unassailable rule in physics, engineering, and, more generally, the natural world. It has been known for over 150 years and is usually considered the most authoritative law.

Earlier, Einstein firmly stated that “Thermodynamics is the only universal physical theory that will never be refuted”. The Second Law and other thermodynamics principles are connected to many perplexing matters that require delicate descriptions and fuzzy interpretations. 

We invite contributions to discuss the fundamental aspects of the Second Law of Thermodynamics, including entropy as a significant physical quantity characterizing a thermodynamic system and entropy generation as an indicator of irreversibility in a thermodynamic process.

We welcome all sorts of relevant topics, such as (but not limited to):

• Entropy and the Second Law;
• Clausius equality and inequality;
• The reversibility and irreversibility of thermodynamic processes;
• Statistical thermodynamics;
• The Second Law of Thermodynamics within a classical and quantum description;
• Low-temperature studies and experiments within the Second Law of Thermodynamics;
• Bose–Einstein condensation and the Second Law of Thermodynamics;
• Quantum coherence, entanglement, and the Second Law;
• Maxwell’s demon and further challenges;
• The Second Law in Cosmology, Gravitation, and Astrophysics.

It is our desire that this Special Issue motivates researchers and specialists to take a closer look at the Second Law of Thermodynamics—one of the most influential fundamental laws of nature—and the issues relevant to it.

Prof. Dr. Roberto Zivieri
Dr. Israa Medlej
Guest Editors

Manuscript Submission Information

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• Second Law of Thermodynamics in physics, chemistry, biology, engineering and natural science
• entropy
• Clausius equality
• Clausius inequality
• reversibility
• irreversibility
• non-equilibrium
• Second Law in quantum theory
• statistical thermodynamics
• Maxwell’s demon