Quantum Mechanics, almost 80 years after its arrival, is a well established and experimentally not falsified theory. It has predicted and explained a whole series of natural phenomena of a very delicate nature. But its interpretation has not gained universal acceptance. Many scientists have considered the conceptual framework of quantum theory to be unsatisfactory. The very foundations of Quantum Mechanics is a matter that needs to be resolved in order to achieve and gain a deep physical understanding of the underlying physical procedures that constitute our world.
Quantum Mechanics, almost 80 years after its arrival, is a well established and experimentally not falsified theory. It has predicted and explained a whole series of natural phenomena of a very delicate nature. But its interpretation has not gained universal acceptance. Many scientists have considered the conceptual framework of quantum theory to be unsatisfactory. The very foundations of Quantum Mechanics is a matter that needs to be resolved in order to achieve and gain a deep physical understanding of the underlying physical procedures that constitute our world.
This paper deals with the problem of the interpretation of quantum mechanics, the nature of physical theory, and the future of physics. First, the question of why there are so many different interpretations of quantum mechanics proposed and accepted by outstanding quantum experts is treated. This requires a discussion of the relation between physics and philosophy and drawing a distinction between a physical formalism and a physical explanation. The Copenhagen interpretation is considered, criticized, and found to be unsatisfactory in some respects. Finally, an interpretation that contains ideas from previous interpretations but which may itself be new, is proposed. Hopefully, this is superior to the previous interpretations. It has, I believe, the advantage of logical clarity. In the process of doing this, I introduce a theory of levels of physical theory, according to which microscopic physical theory, as it develops in successive stages, becomes more and more adaptable to explaining—or at least taking cognizance of—fundamental biological or ultimately psychological phenomena.
The previous chapters contain many examples of the successful application of quantum mechanics to the solution of real physical problems. These represent only a small sample of the wide range of experimental results, spanning just about all areas of physics and chemistry and beyond, that have been successfully explained by quantum theory. So far at least, no quantum-mechanical prediction has been experimentally falsified. Despite these successes, however, many scientists have considered the basic conceptual framework of the subject to be unsatisfactory, and repeated attempts have been made to reinterpret quantum mechanics, or even replace it with a different theory whose philosophical and conceptual basis could be considered more acceptable. In the present chapter we shall explain the reasons for this dissatisfaction and outline some of the reinterpretations and alternative approaches that have been devised. Inevitably many of the questions that arise in this area are matters of opinion rather than fact and, for this reason, some physicists consider that they belong more properly to the realm of philosophy than of physics. However, the conceptual basis of quantum mechanics is so fundamental to our whole understanding of the nature of the physical universe that it should surely be important for physicists to understand the nature of the problems involved, if nothing else.1,2 16.1 THE CONCEPTUAL PROBLEMS In this section we outline some of the main areas of difficulty with a view to more detailed discussion later in the chapter.
Quantum mechanics, a cornerstone of modern physics, elucidates the behavior of particles at the most fundamental level. This paper delves into the foundational aspects and diverse interpretations of quantum mechanics, shedding light on its enigmatic principles and implications. Beginning with a comprehensive overview of the mathematical framework underlying quantum mechanics, including wave functions, operators, and probabilistic interpretations, the study explores key foundational principles such as superposition, uncertainty, and entanglement. Moreover, it critically examines various interpretations of quantum mechanics, including the Copenhagen interpretation, many-worlds interpretation, and pilot-wave theory, elucidating their philosophical underpinnings and empirical consequences. Through a synthesis of theoretical analysis and empirical evidence, this paper navigates the intricate landscape of quantum mechanics, offering insights into its profound implications for our understanding of reality.
The quantum of action was found more then a century ago, but until now the meaning of quantum theory is often claimed to be “unclear” or even “not truly understandable.” Another prejudice is that quantum theory is only relevant for the range of atomic and sub-atomic phenomena. After a century of successful applications without any evidence at odds with the predictions of quantum theory, and in view of the fact that at present quantum theory is at the economic bottom of about one third of the Gross National Product, the need for a comprehensive and even popular understanding of the principles of quantum theory, preferably dispensing with the burden of the full mathematical apparatus, is more urgent than ever. Interestingly, there is a connection between quantum theory and your daily-life experience, suggesting to extend and generalize the Copenhagen interpretation in such a way that the observer and his consciousness is no longer excluded from scientific description. Moreover, Quantum theory is easier to understood, if one realizes that its range of applicability surpasses widely that of quantum mechanics, comparable to the way classical physics surpasses classical mechanics. The essential new aspect is the role of abstract quantum information, referred to as Protyposis. The idea that quantum information can have an ontological status equivalent to matter or energy was developed more than half a century ago, but it is only rather recently that, in view of the success of experimental work, the relevance of quantum information has been widely acknowledged. The concept of abstract quantum information is especially helpful in the understanding of the measuring process.
Abstract In the previous chapters we have shown many successful applications of quantum mechanics, and it would be a major problem not having this excellent theory available. Despite these successes, however, the basic conceptual framework has been considered by many scientists to be unsatisfactory. In this chapter we will outline the standard Copenhagen –G öttingen interpretation and some of the alternative approaches. Quantum mechanics has to be seen as a major part of more basic quantum field theories. Inevitably, many of the questions that arise are matters of opinion rather than of fact, and therefore many physicists consider that they belong more properly to philosophy than to physics. However, the conceptual basis of quantum mechanics is so fundamental to our understanding of nature that it should surely be important to physicists as well. The conception of determinism differs substantially from classical physics because quantum theory predicts only the relative probabilities of different outcomes. The feature of non-locality is another new concept which makes space-like separated events instantaneously entangled.
The foundations and meaning of quantum theory became a central issue to Albert Einstein and Niels Bohr since the onset of their impassioned debate in the 1920s, enriched by the contributions of many other distinguished scientists and philosophers.The questions are not settled down at all, despite the great achievements of the theory, its impressive accordance with experiment and predictive power.The fundamental and technological applications range from cosmology to biology, with the development of invaluable instruments and the design of new materials.Is quantum mechanics a complete or an incomplete theory?Is there an objective reality independent of the observer or is the reality created by the measurements?Are hidden-variable theories justifiable?Is there a quantum theory founded in a local-causal and non-linear approach that formally contains the orthodox linear theory as a special case?Can such a formulation unify classical and quantum physics?Are Heisenberg's uncertainty relations valid in all cases?Here, the subject is addressed as an adaptation of our contribution to the Colloquium "Quantal aspects in Chemistry and Physics.