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Scale-free descriptions of physical systems

In the discussion of evolution in biology, the systemic approach manifested itself as major evolutionary transitions - transitions in complexity growth between large molecules and cells, cells and multicellular organisms. A similar complexity enhancement also occurs in techno-evolution: transistors are turned into microchips, microchips into computers, computers connected into data centers, and data centers into a computer network. The analogy seems clear, but it required obtaining a scale-free theory (a description applicable to systems of any size, for the world of micro-particles considering quantum physics phenomena, but also for macro objects). Scale-free descriptions are applicable to systems of various scales, including living and non-living systems, as well as living conscious beings and populations of living conscious beings (for example, humanity as a whole). Scale-free also implies scale-free in the fourth dimension, time: accounting for the time of system creation, life/operation/use time, but also evolutionary time.

The key became the transition to formulating physical phenomena as informational, as well as explaining the stability of objects in the physical world - why some objects (e.g., molecules or humans) maintain their shape in spacetime. Fields, Glazebrook, Levin, Friston proposed an ontological framework of panpsychism in the form of minimal physicalism to describe physically stable systems as implementing the principle of minimizing free energy and covering the entire spectrum of complexities/scales from elementary particles to humans and societies. Free energy is defined as an informational characteristic of a system, not the traditional energy of mechanical work or electromagnetic work. These systems become more complex from elementary particles through molecules, through systems of bone matter to living beings, where they become more complex from single-celled to multicellular organisms and their populations. All these types of systems decrease Bayesian (or extended Bayesian) in order to account for quantum-like computations in biology - surprise of inconsistency determined by the generative model's expectations vs. real measurements in reality.

This scale-free ontology of physically stable systems is formalized using category theory as a foundation ontology in terms of mereology and expressed in a way that allows describing quantum-like active/embodied inference. This line of ontological engineering demonstrates how to think about the functioning of systems of various evolutionary complexities, including how to apply stochastic considerations to non-ergodic systems, i.e., memory systems. One of the strongest confirmations of arguments in this line was the creation of hybrot, which learned to play Pong: a complex system capable of learning (e.g., a natural neural network) should demonstrate behavior minimizing unpredictability in the external environment, as demonstrated in the experiment.

In fact, this line of work formalized and mathematized the physics-based ideas of the first-generation ontology of the systemic approach, although due to the scale-free nature of the theory, other time scales can also be considered: life cycles of systems and their evolution. The concept of measurement as interactions of systems, rather than passive perception/observation, was developed in quantum physics to address the observer's problem. Interaction of systems leading to change, i.e., creation, is described as the reverse of measurement. This means that any interaction, even molecules as systems with their environment, can be seen as measurement or creation: a molecule is a proto-agent that somehow perceives/cognizes/ measures and/or creates/alters the surrounding world while maintaining its stability in compliance with the principle of minimizing free energy.

This line of reasoning (perception/measurement opposed to change/creation, both being system interactions) was carried out in constructor theory proposed by Deutsch and developed by various researchers in quantum gravity, as scale-free descriptions are particularly needed there. A constructor is a physical device that can maintain its own constancy/stability for a long time, while changing the environment with predefined sequences of operations (e.g., a catalyst molecule, or a robot with a universal computer, or a living being - sufficiently advanced constructors can replicate themselves, participate in evolution). Scale-free physical theories, based on the idea of information-related changes as computations, have proven to be very productive.