Cybernetics is a successful meta‐theory to model the regulation of complex systems from an abstract information‐theoretic viewpoint, regardless of the properties of the system under scrutiny. Fundamental limits to the controllability of an open system can be formalized in terms of the law of requisite variety, which is derived from the second law of thermodynamics and suggests that establishing correlations between the system of interest and a controller is beneficial. These concepts are briefly reviewed, and the chances, challenges and potential gains arising from the generalisation of such a framework to the quantum domain are discussed. image
Cybernetics is a successful meta‐theory to model the regulation of complex systems from an abstract information‐theoretic viewpoint, regardless of the properties of the system under scrutiny. Fundamental limits to the controllability of an open system can be formalized in terms of the law of requisite variety, which is derived from the second law of thermodynamics and suggests that establishing correlations between the system of interest and a controller is beneficial. These concepts are briefly reviewed, and the chances, challenges and potential gains arising from the generalisation of such a framework to the quantum domain are discussed. image
The study of nonequilibrium phenomena in correlated lattice systems has developed into one of the most active and exciting branches of condensed matter physics. This research field provides rich new insights that could not be obtained from the study of equilibrium situations, and the theoretical understanding of the physics often requires the development of new concepts and methods. On the experimental side, ultrafast pump-probe spectroscopies enable studies of excitation and relaxation phenomena in correlated electron systems, while ultracold atoms in optical lattices provide a new way to control and measure the time evolution of interacting lattice systems with a vastly different characteristic time scale compared to electron systems. A theoretical description of these phenomena is challenging because, first, the quantum-mechanical time evolution of many-body systems out of equilibrium must be computed and second, strong-correlation effects which can be of a nonperturbative nature must be addressed. This review discusses the nonequilibrium extension of the dynamical mean field theory (DMFT), which treats quantum fluctuations in the time domain and works directly in the thermodynamic limit. The method reduces the complexity of the calculation via a mapping to a self-consistent impurity problem, which becomes exact in infinite dimensions. Particular emphasis is placed on a detailed derivation of the formalism, and on a discussion of numerical techniques, which enable solutions of the effective nonequilibrium DMFT impurity problem. Insights gained into the properties of the infinite-dimensional Hubbard model under strong nonequilibrium conditions are summarized. These examples illustrate the current ability of the theoretical framework to reproduce and understand fundamental nonequilibrium phenomena, such as the dielectric breakdown of Mott insulators, photodoping, and collapse-and-revival oscillations in quenched systems. Furthermore, remarkable novel phenomena have been predicted by the nonequilibrium DMFT simulations of correlated lattice systems, including dynamical phase transitions and field-induced repulsion-to-attraction conversions.
Despite all negative accounts in many popular and superficial discussions of quantum theory causal and realistic interpretations of the quantum me chanical formalism can be demonstrated to work perfectly well They accept nonlocality as a well established fact and mostly consider a quantum system as analyzable into a local particlelike nonlinearity of a generally nonlocal wavelike mode of some subquantum structure of the vacuum Dirac ether In this view a particle can be considered as being guided along one specific route by the generally nonlocal configurations of superimposed waves which spread along all possible paths of an experimental setup Moreover in the approach of quantum cybernetics an additional focus is on the fact that the energy and momentum of a particle also determine the wave behavior Thus waves and particles are mutually and self consistently defined and quantum cybernetics puts particular emphasis on the circular relationship mediated byplane waves between a quantum system and its macroscopically defined boundary conditions To show how firmly rooted this picture is in the orthodoxquantum theory an example is discussed here on the basis of the standard formalism that makes a systemic approach called for
Purpose As any attempts at explaining quantum theory in terms of simple, local “cause‐and‐effect” models have remained unsatisfactory, approaches from the perspectives of systems theory seem called for, which is rich in a variety of more complex understandings of causality. Design/methodology/approach This paper presents one option for such approaches, which the author has introduced previously as “quantum cybernetics”: considering waves (but not “wave functions”!) and “particles” as mutually dependent system components, and thus defining “organizationally closed systems” characterized by a fundamental circular causality. Using such an approach, a new look can be achieved on both classical and quantum physics. Findings It was found that quantum theory's most fundamental equation, the Schrödinger equation, can actually be derived from classical physics, once the latter is considered anew, i.e. under said approach involving both particles and (Huygens) waves. In fact, the only difference to existing views is that Huygens waves are here considered to be real, physically effective waves in some hypothesized sub‐quantum medium, rather than mere formal tools. Originality/value What is particularly new in the present paper is that quantum systems can be described by what Heinz von Foerster has called “nontrivial machines”, whereas the corresponding classical counterparts turn out to behave as “trivial machines”. This should provide enough stimulus for discussing system theoretical issues also in the context of the foundations of quantum theory.
This study examines how David Bohm’s quantum theoretical principles, embodied in wholeness, implicate order, and holomovement provide innovative frameworks for reconceptualizing sustainable development. Current approaches remain constrained by mechanistic paradigms that fragment economic, environmental, and social systems, limiting transformative solutions to recurring global crises. Through systematic conceptual analysis and cross-disciplinary literature review, this research develops consciousness-based models that transcend fragmented thinking and separated domains by applying quantum metaphysical principles in socio-economic systems in an integrated manner. Comparative systems analysis reveals significant parallels between quantum mechanical principles and economic behavior, demonstrating how Bohm’s framework addresses sustainability challenges through the epistemological and ontological transformation of information rather than mere technical optimization. Generalization and illustrative modeling show how implicate order dynamically enables economic coherence, organizational intelligence, and systemic governance. Expressions are derived for unfolding sustainable development operators and kinematic transformations evolving with quantum economics. Two central quantities emerge: active and passive information, exhibiting close analogies with gravitational pull and sustainability potential, bounded by thermodynamic laws and entropy principles. This formulation corresponds to and transcends the quantum law of syllogism, bridging information theory, quantum mechanics, and sustainability metrics. The 2025 coherence–entropy sustainable development scores findings correlatively unify Shannon entropy, Bohmian coherence, and Feynman extremals. A sustainability law of syllogism was suggested, confirming the systemic coherence of the scores. The Appendix validates Bohm’s concepts, facilitating paradigm shifts from mechanistic control to participatory transformation, establishing theoretical foundations for quantum-informed economics, consciousness-based management, and holistic responses to global sustainability challenges that have become increasingly urgent since Bohm’s original discoveries.
The control of open quantum systems and their associated quantum thermodynamic properties is a topic of growing importance in modern quantum physics and quantum chemistry research. This unique and self-contained book presents a unifying perspective of such open quantum systems, first describing the fundamental theory behind these formidably complex systems, before introducing the models and techniques that are employed to control their quantum thermodynamics processes. A detailed discussion of real quantum devices is also covered, including quantum heat engines and quantum refrigerators. The theory of open quantum systems is developed pedagogically, from first principles, and the book is accessible to graduate students and researchers working in atomic physics, quantum information, condensed matter physics, and quantum chemistry.
Abstract The measurement problem remains one of the most unresolved foundational issues in quantum mechanics. Existing interpretations successfully preserve predictive formalism while diverging sharply on ontology, observer status, and collapse mechanics. This paper proposes a formal framework in which consciousness functions not as an emergent byproduct of material systems but as the rendering condition under which physical determinacy becomes possible. Consciousness is modeled as a substrate-dependent operator Ĉ acting upon quantum potential Ψ and substrate state tensor S to produce rendered physical reality ℛ through recursive temporal processing. This work introduces a two time architecture separating rendering meta time τᵣ from measured physical time τₘ. Within this structure the second law of thermodynamics emerges not as a primitive physical postulate but as a necessary condition for stable recursive rendering. A modified Lindblad master equation incorporating a consciousness coupling channel γ_c(S) is proposed together with a biologically constrained substrate fidelity parameter B grounded in quantum coherence preservation. The proposed advances several experimentally accessible predictions including a decoherence resilience prediction distinguishing conscious observation from equivalent non conscious measurement apparatuses under controlled conditions and an anesthesia transition paradigm for threshold crossing analysis. Open mathematical problems are identified explicitly including the eigenvalue structure of Ĉ, bootstrap conditions for initial rendering, and formal derivation of recursive scaling laws. The paper does not claim completion of the mathematical formalism. It proposes instead a structured theoretical research program situated at the intersection of quantum foundations, information theory, thermodynamics, philosophy of mind, and quantum biology.