La passeggiata nel bosco di un Fisico Tecnico

Strolling is like thinking and they often intertwine, coexist. Thought is always and in any case a wonder, in the double sense of the verb: to wander and to walk astray. On the other hand, walking means being, staying in a place while moving, therefore essentially having already entered the woods and walking while thinking. The walk in the woods is then my way as a technical physicist, to see and think about the woods, or even greenery in general. The walk in the woods is also a path (mental and research) towards future prospects of environmental and energy sustainability. The aim is therefore to provide a way of thinking, reasoning, studying the forest, not solutions, recipes, but perspectives for formulating new questions. This paper shows how the methodological and research approach provided by technical physics can be of great support to the systemic vision that allows us to understand the forest as a complex, dynamic and continuously changing system, its functions and its interactions with the environment. The systemic vision that is proposed is based on the thermodynamic reading of the woods system, through the Second Principle and its applications according to Information Theory, i.e. the correspondence between entropy, resources and information. Entropy, information, communication always produce differences. The woods, as a complex living system is capable of organizing and building itself, producing information, communicating by means of the differences present in the environment. These differences, e.g. due to the sun, allow any form of life. From this point of view, real sustainability can only be achieved when the total flow of entropy due to the irreversibility produced by human activities and various processes is lower than the flow of neg-entropy (information) that comes from the sun. The irreversibility of processes is the natural evolution of any system: the woods evolves by finding many different strategies for all the living forms present in it; it is a continuous building of organized, but transitory and irreversible structures, it is a complex network thermodynamic system.