The Physical Reality of the Quantum Wave Function

Detlef Dürr, Sheldon Goldstein, Nino Zanghı̀

Guolin Wu

Understanding the nature of reality has been a central theme in philosophy for centuries. Classical science presented a well-defined, deterministic view of reality as objects are governed by clear laws. However, quantum mechanics introduced a radically different perspective that suggests a “quantum reality” where particles exhibit wave-like behavior and defy classical intuitions. This chapter delves into the evolution of reality, exploring its characteristics in classical physics and its transformation in the face of quantum mechanics. One key aspect of quantum reality is the wave function, as in whether the wave function is of reality. The Copenhagen interpretation posits that the wave function is a probabilistic tool, rather than a description of the real state of microscopic particles. However, the fundamental principles of quantum control and the very objects it manipulates challenge this view. By directly or indirectly influencing the wave function, quantum control techniques provide compelling evidence for its quantum reality. The PBR theorem suggests that the wave function reflects a real physical state, not merely a mathematical tool. This chapter argues that the wave function is of the “reality of relative entity-structure”. In addition, the “quantum Cheshire cat” experiment further highlights the unusual nature of quantum reality, which shares some connections with the concept of “Tao” in Chinese Taoism that suggests that everything arises from a fundamental nothingness that itself is real. Quantum technology brings forth a “quantum technological reality” characterized by new properties and applications.

Detlef Dürr, Sheldon Goldstein, Zangh\`ı, Nino

We outline how Bohmian mechanics works: how it deals with various issues in the foundations of quantum mechanics and how it is related to the usual quantum formalism. We then turn to some objections to Bohmian mechanics, for example the fact that in Bohmian mechanics there is no back action of particle configurations upon wave functions. These lead us to our main concern: a more careful consideration of the meaning of the wave function in quantum mechanics, as suggested by a Bohmian perspective. We propose that the reason, on the universal level, that there is no action of configurations upon wave functions, as there seems to be between all other elements of physical reality, is that the wave function of the universe is not an element of physical reality. We propose that the wave function belongs to an altogether different category of existence than that of substantive physical entities, and that its existence is nomological rather than material. We propose, in other words, that the wave function is a component of physical law rather than of the reality described by the law.

Steven E. Kaufman

In this article both the inner orientation of emotional and mental experience, as well as the outer orientation of physical experience, are described as a function of our particular position and perspective within the fractal Structure of Reality relative to the particular level of Reality at which each of those different types of experience are created. Additionally, the Relational Structure of Reality is described as the framework that underlies our overall apprehension of mental and physical reality by relating the different levels of Reality to different fundamental aspects of what we apprehend as mental and physical reality. Also described is the relation between what is expressed in quantum physics as the wave function and the underlying Structure of Reality from which that expression is derived, including a description of what occurs within that Relational Structure to produce the event referred to as the collapse of the wave function.

Gennaro Auletta, Gino Tarozzi