The purpose of this paper is, first of all, to indicate the manner in which these quantum concepts were introduced into physical theory and finally coordinated into a consistent interpretation, the Copenhagen interpretation. This is accomplished by an introductory examination of the development of quantum mechanics.
Of all the many rival interpretations of quantum mechanics, none is more important or influential than the Copenhagen interpretation. Unfortunately, there is no one Copenhagen interpretation of quantum mechanics. If one uses the expression, and everyone does, one should not think of the Copenhagen interpretation as a single consistent interpretation of the theory. Philosophers of physics tend to use the expression ‘the Copenhagen interpretation of quantum mechanics’ as a label covering a variety of different interpretations all of which either originate with Niels Bohr or were invented by him, his colleagues and guests at the Institute for Theoretical Physics in Copenhagen beginning in the middle 1920s. Perhaps one should say that the Copenhagen interpretation in this diffuse sense goes back farther than this, back even before the rise of the new quantum mechanics. Heisenberg tells the story of a boat trip he, Bohr, and some friends took from Copenhagen to the island of Fyn around the time when the then new quantum mechanics was being developed. Bohr, ‘full of the new interpretation of quantum theory’, talked of ‘the difficulties of language, of the limitations of all our means of expressing ourselves’ and of how these limitations had been expressed ‘in the foundation of atomic theory in a mathematically lucid way’. ‘Finally,’ Heisenberg ends the story, ‘one of the friends remarked drily, “But, Niels, this is not really new, you said exactly the same ten years ago”
The Copenhagen Interpretation of quantum mechanics has become the standard way of explaining the physical philosophical meaning of the mathematics of microscopic behavior. It developed from the thought of people who attended the Institute for Theoretical Physics of the University of Copenhagen during the 40 years that Niels Bohr directed it, from 1920 to 1962. Bohr took a large part in developing the Copenhagen Interpretation, he didn't escape all controversy over it (although the quote above is a bit of an exaggeration). Bohr did die before the experimental theoretical developments that have transposed the debate over the appropriateness adequacy of the Copenhagen Interpretation into a new key, he may well have been lucky to have escaped when he did. There is no authoritative codification of CI [the Copenhagen Interpretation], write T Gornitz C. E von Weizsacker of the Max Planck Institute in Starnberg, West Germany in' their formal presentation to the recent Loyola Conference on Mathematical Interpretational Problems in Relativistic Quantum Theory, and under the conditions of its origin there probably could not be one.... All prominent authors of the time who wrote on these questions, like Bohr, [Werner] Heisenberg, [Wolfgang] Pauli, J[ohn] v[on] Neumann on one side, [Albert] Einstein [Erwin] Schrodinger on the other, fell, so we feel, into some stammering when they tried to express their own positions. Nevertheless there is what might be called a Copenhagen attitude. It concentrates on observable phenomena, makes statistics probability central to its understanding, considers quantum mechanics primarily a theory of knowledge or information becomes a kind of physica negativa (analogous to a theologia negativa) in trying not to say too much about things that can't be seen or felt. For example, it doesn't much care whether the orbits of electrons in atoms are real or not and, in fact, tends to regard them as unreal. It appears in most textbooks as the standard way of looking at things.
The interpretation of quantum mechanics has been controversial since the introduction of quantum theory in the 1920s. Although the Copenhagen interpretation is commonly accepted, its usual formulation suffers from some serious drawbacks. Based mainly on Bohr's concepts, the formulation assumes an independent and essential validity of classical concepts running in parallel with quantum ones, and leaves open the possibility of their ultimate conflict. In this book, Roland Omnes examines a number of recent advances, which, combined, lead to a consistent revision of the Copenhagen interpretation. His aim is to show how this interpretation can fit all present experiments, to weed out unnecessary or questionable assumptions, and to assess the domain of validity where the older statements apply. The text offers a self-contained treatment of interpretation (in nonrelativistic physics) in a manner accessible to both physicists and students. Although some hard results are included, the concepts and mathematical developments are maintained at an undergraduate level. This book enables readers to check every step, apply the techniques to new problems and make sure that no paradox or obscurity
Heisenberg is one of the founders of quantum mechanics, and one of the pioneers and intellectual leaders of the Copenhagen interpretation of quantum mechanics. He proposed in two seminal papers in 1925 and 1927, the fundamentals of matrix mechanics (1925) as the first formalism of quantum mechanics, and then the uncertainty relations (1927) as one of the essential components of the Copenhagen interpretation. The purpose of this paper is to formulate Heisenberg's philosophical approaches during the formation of quantum mechanics and its Copenhagen interpretation. The main question of the paper is whether philosophical approaches can be formulated in the development of quantum mechanics through Heisenberg's works? To answer this question, two seminal papers by Heisenberg (1925 and 1927) are examined. The research method of the paper is based on the content analysis of the text (physics) of Heisenberg's papers. The findings of this study show that three crucial principles - observability, correspondence, and analogy-can be formulated from Heisenberg's 1925 paper, which has played a key role in the formation of the fundamentals of matrix mechanics. Moreover, from his 1927 paper, some issues are addressed including interpretation, understanding and classical-quantum relation, the role of experience and measurement, the subject of causality, as well as reality. Finally, it is concluded that through these works of Heisenberg, four philosophical approaches can be formulated including empiricism, Unificationism, indeterminism, and anti-causality, as well as anti-realism, which themselves include other sub-approaches.