The observer effect is the fact that observing a situation or phenomenon necessarily changes it. Observer effects are especially prominent in physics where observation and uncertainty are fundamental aspects of modern quantum mechanics. Observer effects are well known in fields other than physics, such as sociology, psychology, linguistics and computer science, but none of these other fields have experienced the same level of publicity and controversy as physics. This may be responsible for the widely held implicit assumption that “real” observer effects are exhibited only by quantum objects and not by classical objects. This misunderstanding may be due, to some extent, to confusing the observer effect with the Heisenberg uncertainty principle and with other quantum uncertainty principles. In fact, observer effects occur in both classical and quantum systems. This article presents a number of examples of observer effects in purely classical processes. It also introduces a framework for understanding and analyzing many of such effects for classical systems. Ignoring observer effects can cause errors in experiments at a macroscopic level where no quantum effects would be discernible. Consequently, there are practical reasons for being careful to address observer effects.
The observer effect is the fact that observing a situation or phenomenon necessarily changes it. Observer effects are especially prominent in physics where observation and uncertainty are fundamental aspects of modern quantum mechanics. Observer effects are well known in fields other than physics, such as sociology, psychology, linguistics and computer science, but none of these other fields have experienced the same level of publicity and controversy as physics. This may be responsible for the widely held implicit assumption that “real” observer effects are exhibited only by quantum objects and not by classical objects. This misunderstanding may be due, to some extent, to confusing the observer effect with the Heisenberg uncertainty principle and with other quantum uncertainty principles. In fact, observer effects occur in both classical and quantum systems. This article presents a number of examples of observer effects in purely classical processes. It also introduces a framework for understanding and analyzing many of such effects for classical systems. Ignoring observer effects can cause errors in experiments at a macroscopic level where no quantum effects would be discernible. Consequently, there are practical reasons for being careful to address observer effects.
A public science essay correcting popular misuse of quantum mechanics. The paper argues that “observer effect” should be replaced in public-facing explanations by “measurement effect,” because quantum measurement concerns physical interaction, detection, decoherence, and record formation rather than human consciousness. It reviews common misunderstandings of the double-slit experiment, Born’s rule, superposition, the uncertainty principle, decoherence, Schrödinger’s cat, Wigner’s friend, entanglement, delayed-choice experiments, quantum erasers, and quantum computing. Keywords:quantum mechanics; quantum measurement; observer effect; measurement effect; decoherence; entanglement; superposition; double-slit experiment; uncertainty principle; quantum mysticism; science communication; quantum computing License recommendation:CC BY 4.0 Suggested category tags:Physics; Quantum Mechanics; Science Communication; Foundations of Quantum Mechanics; Quantum Information
The assumption of an objective world underlying all our experiences is deeply embedded in our everyday thinking and in our language, and has been an unquestioned presupposition of the scientific enterprise for at least four centuries. Yet it is well known that quantum physics raises some highly problematic questions in this respect, questions that are still open, almost a century from the inception of the theory. I would like to propose that these questions stem from deep philosophical assumptions and can be answered in a much more coherent way if we understand the notion of an objective world not as a primary reality, but as an emergent aspect of a primary process that can be described as “experiencing”. A coherent description of the appearance of an objective world in the process of experiencing relies on a certain understanding of what is technically known as the “quantum measurement problem”, i.e. the description of the process of observation in quantum physics, which is the key problematic aspect of the theory. I will propose that the basic features that characterize a quantum observation have a much wider scope, and describe in fact all acquisition of information by an “embodied observer”, in short all experiencing happening in the world. By applying to this larger context work I have done in the more technical frame of the quantum measurement problem it can be shown that the nature of the process of experiencing is such as to inevitably generate the appearance of an objective world. Thus the objectivity of the world, although not primary and ultimately real, is an intrinsic consequence of our “experiential embodiment”, i.e. of the fact that we are in the world and all our experiences correspond to physical happenings in the world. When examined in this perspective, the “paradoxes” of quantum physics are an invitation to abandon the metaphysical assumption of the primacy of the objective dimension of reality. A philosophical position much more in tune with quantum physics views the process of experiencing as the primary source of both subject and object, consciousness and world.
This chapter is a refresher on the fundamental concepts of quantum mechanics. One essential difference between classical and quantum mechanics is that in classical mechanics, we are used to deterministic and precise laws stemming from the fact that the act of measurement can be ignored. Indeed, for all practical purposes, the interaction with the macroscopic system to be measured can be rendered negligibly small. However, at very small scales, the situation changes radically. The assumption that the measurement is ignorable is not true for micro-objects. In order to perform a measurement, we must interact with the system we are measuring. We discovered experimentally that nature has an objective scale, encoded by Planck's constant, that limits our ability to perform perturbation-free measurements. All we can do is perform many measurements on identically prepared systems, which would allow us to determine the probability of a given outcome. Micro-objects behave non-intuitively, described by new laws, those of quantum mechanics. In this chapter, we will briefly cover the postulates of quantum mechanics and introduce the Schrodinger and Heisenberg pictures of quantum mechanics.
Introduction: the study considers the problem of observer’s status during specific quantum-mechanical experiments, in which the empirical result directly depends on the participation of the experimenter's mind. Here the problem arises of the connection between the mind of the observer and the quantum-mechanical description of physical reality. The paper pays attention to modern trends in physics and philosophy devoted to the study of this phenomenon. Some aspects of the philosophical interpretation of the mind as a quantum mechanism are presented. Materials and Methods: the research materials demonstrate an overview of several common quantum-philosophical theories. Attempts have been made to search for the connection of quantum phenomena with the mechanisms of the functioning of human mind. The experimental background of quantum physics is demonstrated, providing material for analyzing the possibility of applying modern quantum theory to the question of identifying the relationship of the quantum approach and describing the problem of the influence of the observer’s mind on the result of a physical experiment. Results: the concept of quantum mechanics, taking into account the latest achievements and results of physics, philosophy and psychology, allows us to consider the mind of the observer as an integral part of the mechanism responsible for the formation of the surrounding physical reality. The anthropic principle of participation considered in the work gives the observer's mind a special role allowing to form a quantum-mechanical description of physical reality. Discussion and conclusions: it is shown that the mind of the observer plays an important role in quantum theory. Moreover, mind as a psychic phenomenon may be in fact identical with the quantum-mechanical concept of choosing an alternative. Given the fact that the brain's thought processes influence the measurement results, it can be assumed that mind changes quantum probabilities. This assumption allows us to take a different look at the concept of reality itself.
This is a multi-disciplinary paper. It borro ws ideas from mathemat ics, engineering software, and digital communicat ion engineering. Uncertainty principle is at the foundation of quantum mechanics. (A) It is well known that this principle is a consequence of Fourier transform (FT). The FT is based on infinity assumption. As infinity is not realistic and mean ingful in nature, and in engineering, we show that replacing in fin ity by any finite value changes the lower bound of the uncertainty principle to any desired accuracy number. (B) The paper points out, that uncertainty principle vio lates a very fundamental and well known concept in mathematics: the infinite d imensionality property of functions over finite intervals. (C) It is important to realize that no engineering experiment can prove any theory. Engineering is created out of objects of nature. Nature does not and cannot make any assumptions. Thus all engineering experimental setups will auto matically eliminate all assumptions from all theories. To establish this obvious and logical fact, we discuss many laws of nature, which modern microprocessor based engineering systems implement. Therefore it is not possible to prove uncertainty principle by any physical experiment, because the principle has many assumptions. (D) We exp lore several published proofs of uncertainty principle, including Heisenberg's and Operator theoretic, and analyze the assumptions behind them to show that this theory cannot be a law of nature. The paper ignores the relativistic effects.
Any complete theory of physical reality must allow for the ubiquitous phenomenon of subjective experience at some level, or risk being conceptually incoherent. However, as long as the ontological status of subjectivity itself remains unresolved, the topic will be seen as more within the purview of philosophy than of physics. Towards a resolution of this issue within empirically motivated physical theory, this article introduces an operational definition that ultilizes the general consensus that subjective mental states, whatever else is controversial about them, at least correlate in some way to physical states. It is shown here that implementing this underappreciated assumption within the framework of a physical theory in fact leads to wide-ranging consequences. In particular, a correlation requires there exist a well-defined mapping from a space of subjective mental states onto a space of information-bearing elements of some physical theory. Given the peculiar nature of subjective states as inherently private appearances, any empirical identification of states must be performed by the experiencing subject. It is argued that such an operationally defined 'self-measuring' act leads unavoidably to an 'uncertainty principle' that is analogous in some intriguing ways to Heisenberg's principle for quantum mechanics. A model is then introduced for subjective states as algorithmically incomputable numbers. Additionaally, an inequality similar to Bell's theorem may be derived, indicating an analogy with the violations of local reality and the ontology of observables within quantum mechanics.