Note that the formalism covers more complex forcible interrelationships of physical forces and processes, like magnetohydrodynamics involving the interactions of electromagnetic, mechanical, thermal, and hydrodynamic forces.
It is crucial, each complete process is a force-interralationship, a forcible and energetic relationship of cause (an input change or energy or power or force) to effect (an output change or energy or power or force) which in order to occur requires a specific physical entity, object, system, material, or force field. Now, depending on the physical properties of a given material entity (size, mass, composition, weight, temperature, magnetization, etc.), a given process can be materialized as various physical effects subject to measurements and experimental observations.
Basing on the mathematical model of physical processes, we could develop a unique knowledge innovation product: the global base in physical science for AI, added with functional descriptions readable by machines.
The totality of physical phenomena and reversibility of all physical effects is enabling to create Encyclopedic Knowledge Base in Physics for General AI systems.
(А. Ш. Абдуллаев; База знаний энциклопедического искусственного интеллекта: Об исследовательском прототипе энциклопедической системы по физике, Москва, ВИНИТИ, 1989).
How Modern Physics Reversibility Lost
The reason why the Reversibility Principle of the Physical Universe has been missing as the fundamental law of nature is the matter of scientific methodology: how we see and formalize the cause-effect relationship, the most important concept in empirical sciences. It is often overstated that “the great conceptual revolutions of modern natural science of physics” consisted in displacing the “causal interactions of physical entities” with the “functional relationships of variables””.
Here is a standard approach typified by Nobel Prize laureate Herbert A. Simon claiming the asymmetry of a causal relation, that a strict ordering is its key feature, that it is an asymmetrical relation between variables or their values, a function of one variable (the cause) on to another (the effect). And that, given a system of equations and a set of variables appearing in these equations, one can introduce a series of asymmetric relations among individual equations and variables following such a partial notion of a causal ordering of physical processes.
In physical sciences, theoretical causality is viewed as a lawful relationship of general changes to matter and energy occurring to different objects in different places at different times, involving fundamental processes and physical effects, where the input variables function as causes and the output variables as effects.
On the other side, physical causation, the working causality, will be the actual productive connections among distinct change-occurrences happening to a specific object (or a system of objects) at a unique spatiotemporal location. This level applies to so-called “singular causation”, deterministic or probabilistic, as a temporally ordered asymmetrical and irrefexive relation of individual events, still acting in forward or backward directions.
As a matter of physical science, the efficient interrelationships among physical changes are expressed by symmetrical differential equations containing change-differentials of a state function, such as:
Maxwell’s equations describing the changes of electromagnetic field;
Schrodinger’s wave equation, the basic equation of wave mechanics;
Einstein’s equations describing the changes of gravitation field.
In the equations, change of quantities (or of the state functions f(x), F (x)) is mathematically represented either as a differential d, increment ?, derivative dy/dx with respect to x, or as a variation ?.
This all leads to the following significant conclusion. Underlying all the formal interrelations of physical changes in the state variables, reciprocal forceful relationships determine the structure of the physical world, its phenomena and mechanisms, as well as the physical artifacts, their structures and functions, as applications designed to realize in practice natural effects or processes.
For instance, the operation and the components of such important devices as electric generators, transforming mechanical motions from primary sources to electricity, and electric motors, converting electric energy to mechanical phenomena using electromagnetic induction, is regulated by two convertible principles, Ampere’s law and Faraday’s law. Since the same reversible natural process underlies the laws and the action of the physical artifacts, both electric machines are complementary: motors may work as generators and inversely, generators may function as motors.
The Engine of the Physical World
There are remarkable laboratory experiments directly suggesting or testifying to the Reversal Principle in Nature. And they are as diverse as the classic Faraday experiments of relationships of magnetism, electricity and gravitation, QM test of Bell's inequalities with correlated photons, the asexual genetic cloning of a mammal using adult somatic cells, and the rescue of somatic cells from senescent death.
At first sight, the experimental tests were designed to illustrate different truths of nature, like as. 'An experimental polarization of Einstein-Podolsky-Rosen type correlation' is thought to bear witness of spatial-temporal and causal non-localities of physical quantum reality. Or, the nuclear transplantation test discovered that the genetic material of adult somatic cells doesn't undergone irreversible changes. Or, ageing is not an irreversible process, but must be completed with its opposite process, rejuvenation. The cell aging experimental research established 'a causal relationship between telomere shortening and in vitro cellular senescence'; what became possible by the discovery of the reverse transcriptase subunit of telomerase from eukaryotes.
In fact, the laboratory experiments once more tested that the inherent quality of any natural processes to run both forward and backward also applies to all natural phenomena, electro-magnetic effects, biochemical reactions or quantum physical processes. Faraday’ effects, Bell's inequalities, the asexual genetic cloning of mammals, and the extension of somatic human cells' lifetime, all this do testify to the universal fact of Nature – the process reversal mechanism.
The rule that any natural process (phenomena) has a converse (relation), that any natural phenomenon (physical, chemical and biological) caused by some previous phenomenon is to be reversed in its order of action, has a profound extent and depth. The rule states that the opposite of physicochemical phenomena, where physical change produces chemical change, is the chemo-physical phenomena, where the chemical changing inversely produce changes in the states of physical systems. The same happens with biophysical and physico-organic processes standing in converse relations of actions and influences.
The case of leading natural science, physical science, studying matter and energy and their interactions, can be fundamental to the argument of process reversibility or convertibility, though with some important reservations. The process reversal shouldn't be confused with the physical notion of reversibility of thermodynamics. For the latter implies reverse changes of a system from a final state to its initial position, like the reversible processes of a mathematical (frictionless) pendulum, where we only observe the inversion of the order of states involving one thing or the inversion of the order of changes again involving one and the same thing, simple or complex.
In fact, a real natural process is to be identified with an efficient interrelation between changes of distinct systems, or distinct processes. Things receiving a change, as passing-away, coming-to-be, alteration, or any another sort of change whatsoever, must be of different sorts, one system may undergo the processes of passing-away, another coming into existence, growth or degeneration, useful or harmful alterations, increase or decrease, forward motion or reverse motion.
For the case of the real pendulum, the physical device consists of two distinct objects (or systems) undergoing distinct changes, a compressed spring and a swinging pendulum, which are acting on each other.
So, there is the thermodynamic reversibility of the way of behavior in the equilibrium state, without exchanging matter or energy, and the universal natural reversibility of the order of actions of force-relationships of energy and power.
To sum up, any physical phenomena has a reversed process, any physical effect has a converse, the reciprocal, reverse, inverse, opposite effect, where the change-cause and the change-effect are turned about in order of interactive relationship.
The reversibility principle is universal in its scope and scale, applying to the dynamics of the whole universe as well. That means if there is "the accelerating expansion of the Universe”, so there must be (or going to be) a cosmic retrogression, or the universe’s retroaction: "the accelerating compression of the Universe”, to reach a true cyclic model of the universe.
Gravity or gravitation, as the universal force of attraction affecting all matter, as with other fundamental forces being both attracted and repelled, must have its counterpart, antigravity, as the proposed “gravitation repulsion” in a number of “dark forces” theories, with nonidentical particles and antiparticles of gravitons and antigravitons, as the massless? carriers of the gravitation fields of attraction and repulsion.
If the entropic regression from order to disorder is about chaotic disruptions of structure and organization of the universe, then its inverse, the entropic progression from disorder to order is about creative disruptions of structure and organization of the universe.
Process Reversibility as the Ground for Symmetry and Conservation
In all, the description of physical phenomena is rested on several basic concepts: matter or substance or body, energy, states, time and space, cause, motion and changes, interactions, and systems, the distinct collections of matter. Most of them are presented as physical quantities:
Matter by mass, as related to weight, and subject the law of conservation: matter is neither created nor destroyed, but converted and reversed;
State by energy, mechanical, potential, kinetic, thermal, atomic, etc., subject to the law of conservation: energy is neither created nor destroyed, but only converted from one form to another;
Change by motion, measured by momentum, velocity and acceleration;
Duration by time, which is numbering change and motion;
Extension by space: the matrix of figures and distance;
Cause by force and force fields, the powerful force-relation, integrating mass, distance, direction, momentum, velocity and acceleration, and defining the operating symmetries, invariances, uniformities, transformations, and the conservation laws.
Most physical quantities, as mass, energy, momentum, electric charge, are subject to the correlated Principle of Conservation and Symmetry stating that nature remains constant with the passage of time, and most physical laws are subject to the Symmetry Principle implying that “all the laws remain valid in any time or place in the world”.
Its ideas of physical symmetry and that processes changing the physical or chemical properties of substances (within an isolated system) leave some total quantities, mass, energy or mass-energy, unchanged or invariant during interactions are correlated with the prime concept of the Force-as-active-reactive-Relationship, the Principle of Reversibility and the Laws of Convertibility.
It is thus allowing predicting the behavior of any system, natural or social, without considering the detailed course of a process, be it a natural process, chemical reaction, biological processes, conscience, a set of responses to social stimuli, or consciousness, mental actions toward natural objects, the environment conservation, or social interactions.
To know the states of systems is to know all the possible properties, measured or observed, while to know the changes of states of systems is to know all the possible actions, alterations and modifications, manifested as different sorts of forces and fluctuations of force fields represented as changes of physical quantities.
To know all the possible relationships among changes is equivalent to knowing the results and outcomes of all possible interactions among systems, and thus being able to explain or predict the behavior of complex physical entities (objects and force fields, gravitational, electromagnetic, nuclear) under the action of given forces.
Reversing All Processes and Converting All Forces and Effects: to Encyclopedic Knowledge Base in Physics
It is the universality of the reversibility of physical processes and convertibility of natural forces and thence their inherent unity inspired Faraday, Maxwell and Einstein to seek unification of all the physical processes by a single set of physical laws.
It is the universality and completeness and reversibility of scientific laws enabled all the variety of modern technological applications.
It is the universality and completeness and reversibility of the conservation principles, like the energy conservation and transformation laws, enabled all kinds and manner of productive applications like energy-conversion systems, from chemical batteries to thermonuclear fusion reactors.
It is the reversibility principle and its correlative of the conservation law of energy determines all the energy changes from one form to another: nuclear, radiant, mass, gravitational, kinetic, thermal, elastic, electrical, and chemical.
Again, it is the reversibility principle and its correlative of the conservation law is enabling the relativity theory, the principle of interdependence of matter, energy, space and time, as mathematically formulated by Einstein.
Currently, there may be about 10000 physical effects specified by a multitude of physical materials, systems, or force fields, of which the most part happens to represent only one-side effects.