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Quantum Mechanics Mysteries: Reality, Observer, Prediction, Collapse, and Correlated States

Ana Elisa D. Barioni, Felipe Boechat Mazzi, Elsa Bifano Pimenta, Willian Vieira dos Santos, Marco A. P. Lima

Published Jun 3, 2021• 0 citations
OpenAlex

Abstract

How come such a successful theory like Quantum Mechanics has so many mysteries? The history of this theory is replete with dubious interpretations and controversies. The knowledge of its predictions, however, caused the amazing technological revolution of the last hundred years. In its very beginning Einstein pointed out that there was something missing due to contradictions with the relativity theory. So, even though Quantum Mechanics explains all the physical phenomena, due to its mysteries, there were many attempts to find a way to ``complete it, e.g. hidden-variable theories. In this paper, we present these mysteries, with special attention to the concepts of physical reality imposed by quantum mechanics, the role of the observer, prediction limits, definition of collapse, and how to deal with correlated states (the basic strategy for quantum computers and quantum teleportation). The discussion is carried out by accepting that there is nothing important missing. We are just restricted by the limitations imposed by quantum mechanics. The mysteries are cleared out by a proper interpretation of these limitations. This is done by introducing two interpretation rules within the Copenhagen interpretation.

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How come such a successful theory like Quantum Mechanics has so many
mysteries? The history of this theory is replete with dubious interpretations
and controversies. The knowledge of its predictions, however, caused the
amazing technological revolution of the last hundred years. In its very
beginning Einstein pointed out that there was something missing due to
contradictions with the relativity theory. So, even though Quantum Mechanics
explains all the physical phenomena, due to its mysteries, there were many
attempts to find a way to ``complete it, e.g. hidden-variable theories. In
this paper, we present these mysteries, with special attention to the concepts
of physical reality imposed by quantum mechanics, the role of the observer,
prediction limits, definition of collapse, and how to deal with correlated
states (the basic strategy for quantum computers and quantum teleportation).
The discussion is carried out by accepting that there is nothing important
missing. We are just restricted by the limitations imposed by quantum
mechanics. The mysteries are cleared out by a proper interpretation of these
limitations. This is done by introducing two interpretation rules within the
Copenhagen interpretation.
Why does such a successful theory like Quantum Mechanics have so many mysteries? The history of this theory is replete with dubious interpretations and controversies, and yet a knowledge of its predictions, however, contributed to the amazing technological revolution of the last hundred years. In its very beginning Einstein pointed out that there was something missing, due to contradictions with the relativity theory. So, even though Quantum Mechanics explains all the nanoscale physical phenomena, there were many attempts to find a way to “complete” it, e.g. hidden-variable theories. In this paper, we discuss some of those enigmas, with special attention to the concepts of physical reality imposed by quantum mechanics, the role of the observer, prediction limits, a definition of collapse, and how to deal with correlated states (the basic strategy for quantum computers and quantum teleportation). That discussion is carried out within the framework of accepting that there is in fact nothing important missing, rather we are just restricted by the limitations imposed by quantum mechanics. The mysteries are thus explained by a proper interpretation of those limitations, which is achieved by introducing two interpretation rules within the Copenhagen paradigm.
For over nine decades, quantum mechanics has profoundly shaped our understanding of nature, offering explanations for the stability of atoms, the formation of mole cules, the properties of materials, and phenomena such as light or radioactivity. It is essential to modern technologies—from microchips to lasers—and underpins the physics of elementary particles. Yet, despite its successes, it remains a deeply mysterious theory, confronting a central enigma: why does the quantum world behave so differently from everyday reality? Elements such as superposition and quantum entanglement—which allow particles to exist simultaneously in multiple states or remain interconnected regardless of distance—contradict classical world intuitions. This gap between microscopic and macroscopic behavior has given rise to what is known as the “measurement problem,” raising fundamental questions about the nature of reality. Diverging interpretations have led to two major schools of thought: anti-realism, promoted by Niels Bohr, which holds that reality depends on the observer and their interaction with measurement instruments; and realism, supported by Albert Einstein, which argues that quantum mechanics is incomplete and that eality exists independently of observation. Bohr’s complementary philosophy and Heisenberg’s uncertainty principle were central to the formulation of the “Copenhagen interpretation,” which became dominant in the 20th century. However, the persistent opposition of scientists like Einstein and Schrödinger inspired generations of physicists to seek a unification between quantum mechanics and relativity, culminating in new theories such as loop quantum gravity and string theory. Thus, the debate between realism and anti-realism remains alive, and philosophy continues to play a crucial role in exploring the new foundations of physics.
Quantum mechanics is an immensely successful theory, occupying a unique position in the history of science. It has solved mysteries ranging from macroscopic superconductivity to the microscopic theory of elementary particles and has provided deep insights into the nature of vacuum on the one hand and the description of the nucleon on the other. Whole new fields such as quantum optics and quantum electronics owe their very existence to this body of knowledge. However, despite the stunning successes of quantum mechanics, there is no general agreement on the conceptual foundations and interpretation of the subject. The theory provides unambiguous information about the outcome of a measurement of a physical object. However, many feel that it does not provide a satisfactory answer to the nature of the “reality” we should attribute to the physical objects between the acts of measurement. The conceptual difficulty comes about because the wave function |ψ〉 is usually given by a coherent superposition of various distinguishable experimental outcomes. If we denote the collection of states that represent the possible outcomes of an experiment by |ψ j 〉, then |ψ〉 = ∑ j c j |ψ j 〉 where c j = 〈ψ j |ψ〉. The probability of the outcome |ψ j 〉 is P j =|c j | 2 . In the process of measurement, the so called collapse of the wave function takes place and a single, definite state |ψ i 〉 of the physical object is chosen. The difficulty comes about in the interpretation of the mechanism by which this definite state is chosen from amongst all the possible outcomes.
Preface to the 2nd edition. Preface. Acknowledgements. Reality in the quantum world: The quantum revolutions External reality The potential barrier and the breakdown of determinism The experimental challenge to reality Summary of chapter one. Quantum theory: The description of a particle in quantum theory The wavefunction The potential barrier according to quantum mechanics Interference Other applications of quantum theory Summary of chapter two. Quantum theory and external reality: Review of the problem The ensemble interpretation of quantum mechanics The wavefunction as a measure of our knowledge The wavefunction as part of external reality Measurement in quantum theory Interference and macroscopic objects Can quantum mechanics be changed so that it will reduce wavefunctions? Summary of chapter three. Consciousness: The relevance of conscious observers: What is a conscious observer? Does wavefunction reduction require conscious observers? God as the conscious observer The many-worlds interpretation Summary of chapter four. Hidden variables and non-locality: Review of hidden-variable theories The pilot wave The Einstein-Podolsky-Rosen thought experiment Bell's theorem Experimental verification of the non-local predictions of quantum theory Can signals travel faster than light Summary of chapter five. The mysteries of the quantum world: Where are we now? Quantum theory and relativity Where do we go next? Early history and the Copenhagen interpretation A bibliography and some recent opinions A final plea for reality A last look at the wavefunction Conclusions. Recent developments: Models with explicit collapse The Bohm model Many worlds Time and quantum theory A peculiarly quantum measurement Locality. Appendices. Index.
Modern scientists describe the universe in terms of two basic partial theories: firstly, the general theory of relativity proposed by Albert Einstein, and secondly, the theory of quantum mechanics. This theory introduces an immense reality and simultaneously creates complex questions for the world of physics. Quantum mechanics is an incompletable knowledge however scientists are finding the basic theories from this theory. They propose complex mathematical expressions from quantum mechanics to prove the basic law of atoms. Quantum mechanics is the entire knowledge of subatomic particles such as electrons, protons, and neutrons. Quantum mechanics reveals that what we see is just a part of a deeper reality. Then we can grasp from this theory that the material world is not the completed reality; there are other things beyond human physical senses. The concept of quantum mechanics describes particles that can exist in multiple states. The concept of quantum mechanics is directly proportional to contemporary world technologies. The super specialty of this theory is that scientists cannot be explained universe without quantum mechanics. The uncertainty principle of Heisenberg in quantum mechanics suggests that there are limits to what we can know about a particle state of an atom. Humans cannot yet find out what it looks like and how we can imagine the existence of subatomic particles in an atom. That was an unseen dynamite for humans' perspective observation of the material world.
This paper deals with the development of, and the current discussion about, the interpretation of quantum mechanics. The following topics are discussed: 1. The Copenhagen Interpretation, 2. Formal Problems of Quantum Mechanics, 3. Process of Measurement and the Equation of Motion, 4. Macroscopic Level of Description, 5. Search for Hidden Variables, 6. The Notion of “Reality” and Epistemology of Quantum Mechanics, 7. Quantum Mechanics and the Explanation of Life. The Bohr-Einstein dialogue on the validity of the quantum mechanical description of physical reality lasted over two decades. Since the early nineteen fifties, Wiper has provided much of the point and counterpoint of the continuing discussion on the interpretation and epistemology of quantum mechanics. We have explored Wiper's views in some detail against the background of historical development and current debate.