Abstract
Thermodynamic laws and principles overarch all domains of physics, chemistry and biology. In this broad perspective, further generalizations with respect to the "state-of-the-art" of current theories are still viable considering all aspects of systems' states and phenomena. This research aims to discuss the physical and informational implications of Carnot and Joule cycles and the properties inferred from their definitions, as well as the extrema principles governing non-equilibrium phenomena in complex systems. The approach adopted can be viewed as an analytical variational method focusing cycles' performances and maxima of properties and parameters along cyclic processes. The dualisms and symmetries characterizing Carnot and Joule cycles imply the inference of the necessity and sufficiency of the stable equilibrium for equality of thermodynamic potentials of any system in any state. The conclusions provide a perspective on complex systems and non-equilibrium processes governed by the extrema principles and the physical and informational properties relating to complexity and self-organization. This treatise also represents a basis and a proposal for further developments looking forward to unifying thermodynamic and informational aspects of extrema principles in the direction of complexity, self-organization, constructal emergence and autopoiesis of non-living and living systems in the frame of a general unifying paradigm. Implications and applications are envisaged in an extended perspective accounting for sustainability, circularity and biotechnologies representing future scenarios of industry and environmental protection.