Quantum Magic and Quantum Mystery

1989 ◽  
Author(s):  
Roger Penrose ◽  
Martin Gardner
Keyword(s):  
Quantum Theory ◽  
Free Will ◽  
Common Sense ◽  
Physical Reality ◽  
Quantum Level ◽  
Common View ◽  
Classical Physics ◽  
Classical World ◽  
The World ◽  
Mathematical Equations

In classical physics there is, in accordance with common sense, an objective world ‘out there’. That world evolves in a clear and deterministic way, being governed by precisely formulated mathematical equations. This is as true for the theories of Maxwell and Einstein as it is for the original Newtonian scheme. Physical reality is taken to exist independently of ourselves; and exactly how the classical world ‘is’ is not affected by how we might choose to look at it. Moreover, our bodies and our brains are themselves to be part of that world. They, also, are viewed as evolving according to the same precise and deterministic classical equations. All our actions are to be fixed by these equations - no matter how we might feel that our conscious wills may be influencing how we behave. Such a picture appears to lie at the background of most serious 1 philosophical arguments concerned with the nature of reality, of our conscious perceptions, and of our apparent free will. Some people might have an uncomfortable feeling that there should also be a role for quantum theory - that fundamental but disturbing scheme of things which, in the first quarter of this century, arose out of observations of subtle discrepancies between the actual behaviour of the world and the descriptions of classical physics. To many, the term ‘quantum theory’ evokes merely some vague concept of an ‘uncertainty principle’, which, at the level of particles, atoms or molecules, forbids precision in our descriptions and yields merely probabilistic behaviour. Actually, quantum descriptions are very precise, as we shall see, although radically different from the familiar classical ones. Moreover, we shall find, despite a common view to the contrary, that probabilities do not arise at the minute quantum level of particles, atoms, or molecules - those evolve deterministically - but, seemingly, via some mysterious larger-scale action connected with the emergence of a classical world that we can consciously perceive. We must try to understand this, and how quantum theory forces us to change our view of physical reality.

Causality Then and Now

1993 ◽  
Vol 10 (2) ◽  
pp. 165-177
Author(s):  
Karen Harding
Keyword(s):  
Quantum Theory ◽  
Common Sense ◽  
Mechanical Model ◽  
Physical World ◽  
Scientific Data ◽  
The World ◽  
The Common ◽  
The Universe ◽  
The Way

Ate appearances deceiving? Do objects behave the way they do becauseGod wills it? Ate objects impetmanent and do they only exist becausethey ate continuously created by God? According to a1 Ghazlli, theanswers to all of these questions ate yes. Objects that appear to bepermanent are not. Those relationships commonly tefemed to as causalare a result of God’s habits rather than because one event inevitably leadsto another. God creates everything in the universe continuously; if Heceased to create it, it would no longer exist.These ideas seem oddly naive and unscientific to people living in thetwentieth century. They seem at odds with the common conception of thephysical world. Common sense says that the universe is made of tealobjects that persist in time. Furthermore, the behavior of these objects isreasonable, logical, and predictable. The belief that the univetse is understandablevia logic and reason harkens back to Newton’s mechanical viewof the universe and has provided one of the basic underpinnings ofscience for centuries. Although most people believe that the world is accutatelydescribed by this sort of mechanical model, the appropriatenessof such a model has been called into question by recent scientificadvances, and in particular, by quantum theory. This theory implies thatthe physical world is actually very different from what a mechanicalmodel would predit.Quantum theory seeks to explain the nature of physical entities andthe way that they interact. It atose in the early part of the twentieth centuryin response to new scientific data that could not be incorporated successfullyinto the ptevailing mechanical view of the universe. Due largely ...

Determinism and indeterminism

2018 ◽  
Author(s):  
Jeremy Butterfield
Keyword(s):  
Seventeenth Century ◽  
Quantum Theory ◽  
Physical Science ◽  
Physical Theory ◽  
Classical Physics ◽  
Tentative Conclusion ◽  
Open Questions ◽  
The World ◽  
Determinism And Indeterminism

Over the centuries, the doctrine of determinism has been understood, and assessed, in different ways. Since the seventeenth century, it has been commonly understood as the doctrine that every event has a cause; or as the predictability, in principle, of the entire future. To assess the truth of determinism, so understood, philosophers have often looked to physical science; they have assumed that their current best physical theory is their best guide to the truth of determinism. It seems that most have believed that classical physics, especially Newton’s physics, is deterministic. And in this century, most have believed that quantum theory is indeterministic. Since quantum theory has superseded classical physics, philosophers have typically come to the tentative conclusion that determinism is false. In fact, these impressions are badly misleading. The above formulations of determinism are unsatisfactory. Once we use a better formulation, we see that there is a large gap between the determinism of a given physical theory, and the bolder, vague idea that motivated the traditional formulations: the idea that the world in itself is deterministic. Admittedly, one can make sense of this idea by adopting a sufficiently bold metaphysics; but it cannot be made sense of just by considering determinism for physical theories. As regards physical theories, the traditional impression is again misleading. Which theories are deterministic turns out to be a subtle and complicated matter, with many open questions. But broadly speaking, it turns out that much of classical physics, even much of Newton’s physics, is indeterministic. Furthermore, the alleged indeterminism of quantum theory is very controversial: it enters, if at all, only in quantum theory’s account of measurement processes, an account which remains the most controversial part of the theory.

scholarly journals On the Need for a Certain Physicality from Quantum Theory

2017 ◽  
Vol 13 (3) ◽  
pp. 4747-4750
Author(s):  
Devin Hardy
Keyword(s):  
Quantum Theory ◽  
Large Scale ◽  
Translational Motion ◽  
Physical Reality ◽  
Physical World ◽  
The World ◽  
Fundamental Error ◽  
Future Outcomes ◽  
Physical Mechanics ◽  
Mathematical Construct

Many attempts have been made at the unification of General Relativity (GR) and Quantum Theory (QT), but there is a fundamental error made with these attempts, as we will discuss. What is the point of such theories? Well, obviously to describe the physical world we live in. QT describes what happens on the tiny scale, and GR describes what happens to bodies on a large scale. The fundamental error in unifying the two subjects is that QT doesn’t provide the physical happenings for GR to work, or in other words, QT describes why the world is the way it is, but not how, and this does not philosophically suffice in GR. Must we simply give up, in that the subjects are two different entities? I think the answer is that we mustn’t. I think that we should put one theory in terms of the basic mechanics of the other, perhaps by simplifying, or perhaps by taking the physical reality to be our guide. Do I believe QT describes the world? Accurately. Do I believe that QT is the physical truth? Of course not… it is simply a mathematical construct to provide a model that allows for us to predict future outcomes. I will begin very simplistic, but the goal for the first part of the paper is to Classically describe the physical mechanics of QT. I will stick with particles in their ground state, and hence no translational motion.

Determinism and indeterminism

2018 ◽  
Author(s):  
Jeremy Butterfield
Keyword(s):  
Seventeenth Century ◽  
Quantum Theory ◽  
Philosophy Of Science ◽  
Physical Science ◽  
Physical Theory ◽  
Possible Worlds ◽  
Classical Physics ◽  
Tentative Conclusion ◽  
The World ◽  
Determinism And Indeterminism

Over the centuries, the doctrine of determinism has been understood, and assessed, in different ways. Since the seventeenth century, it has been commonly understood as the doctrine that every event has a cause; or as the predictability, in principle, of the entire future. To assess the truth of determinism, so understood, philosophers have often looked to physical science; they have assumed that their current best physical theory is their best guide to the truth of determinism. Most have believed that classical physics, especially Newton’s physics, is deterministic. And in this century, most have believed that quantum theory is indeterministic. Since quantum theory has superseded classical physics, philosophers have typically come to the tentative conclusion that determinism is false. In fact, these impressions are badly misleading, on three counts. First of all, formulations of determinism in terms of causation or predictability are unsatisfactory, since ‘event’, ‘causation’ and ‘prediction’ are vague and controversial notions, and are not used (at least not univocally) in most physical theories. So if we propose to assess determinism by considering physical theories, our formulation of determinism should be more closely tied to such theories. To do this, the key idea is that determinism is a property of a theory. Imagine a theory that ascribes properties to objects of a certain kind, and claims that the sequence through time of any such object’s properties satisfies certain regularities. Then we say that the theory is deterministic if and only if for any two such objects: if their properties match exactly at a given time, then according to the theory, they will match exactly at all future times. Second, this improved formulation reveals that there is a large gap between the determinism of a given physical theory, and the bolder, vague idea that motivated the traditional formulations: the idea that the world as a whole, independent of any single theory, is deterministic. Admittedly, one can make sense of this idea by adopting a sufficiently bold metaphysics: namely, a metaphysics that accepts the idea of a theory of the world as a whole, so that its objects are possible worlds, and determinism becomes the requirement that any two possible worlds described by the theory that match exactly at a given time also match exactly at all future times. But this idea cannot be made sense of using the more cautious strategy of considering determinism as a feature of a given physical theory. Third, according to this more cautious strategy, the traditional consensus is again misleading. Which theories are deterministic turns out to be a subtle and complicated matter, with many questions still open. But broadly speaking, it turns out that much of classical physics, even much of Newton’s physics, is indeterministic. Furthermore, the alleged indeterminism of quantum theory is very controversial: it enters, if at all, only in quantum theory’s account of measurement processes, an account which remains the most controversial part of the theory. These subtleties and controversies mean that physics does not pass to philosophers any simple verdict about determinism. But more positively, they also mean that determinism remains an exciting topic in the philosophy of science.

scholarly journals A no-go theorem for theories that decohere to quantum mechanics

2018 ◽  
Vol 474 (2214) ◽  
pp. 20170732 ◽  
Author(s):  
Ciarán M. Lee ◽  
John H. Selby
Keyword(s):  
Quantum Mechanics ◽  
Quantum Theory ◽  
Incomplete Information ◽  
Experimental Evidence ◽  
Fundamental Theory ◽  
Classical Physics ◽  
Lack Of Information ◽  
The World ◽  
Physical Principles ◽  
Effective Description

To date, there has been no experimental evidence that invalidates quantum theory. Yet it may only be an effective description of the world, in the same way that classical physics is an effective description of the quantum world. We ask whether there exists an operationally defined theory superseding quantum theory, but which reduces to it via a decoherence-like mechanism. We prove that no such post-quantum theory exists if it is demanded that it satisfy two natural physical principles: causality and purification . Causality formalizes the statement that information propagates from present to future, and purification that each state of incomplete information arises in an essentially unique way due to lack of information about an environment. Hence, our result can be viewed either as evidence that the fundamental theory of Nature is quantum or as showing in a rigorous manner that any post-quantum theory must abandon causality, purification or both.

scholarly journals Is Mind Quantum?

2021 ◽  
Author(s):  
Stuart Kauffman ◽  
Dean Radin
Keyword(s):  
Free Will ◽  
Active Role ◽  
Physical World ◽  
Present Evidence ◽  
Classical Physics ◽  
Substance Dualism ◽  
The World ◽  
The Mind ◽  
Excluded Middle ◽  
Oriented Approach

If all aspects of the mind-brain relationship were adequately explained by classical physics, then there would be no need to propose alternative views. But faced with possibly unresolvable puzzles like qualia and free will, other approaches are required. We propose a non-substance dualism theory, following a suggestion by Heisenberg, whereby the world consists of both ontologically real Possibles that do not obey Aristotle’s law of the excluded middle, and ontologically real Actuals, that do obey the law of the excluded middle. Measurement converts Possibles into Actuals. This quantum-oriented approach solves numerous puzzles about the mind-brain relationship, but it also raises the intriguing possibility that some aspects of mind are nonlocal, and that mind plays an active role in the physical world. We suggest that the mind-brain relationship is partially quantum, and we present evidence supporting that proposition.

scholarly journals Nature Has No Elementary Particles and Makes No Measurements or Predictions: Quantum Measurement and Quantum Theory, from Bohr to Bell and from Bell to Bohr

Entropy ◽  
2021 ◽  
Vol 23 (9) ◽  
pp. 1197
Author(s):  
Arkady Plotnitsky
Keyword(s):  
Field Theory ◽  
Quantum Theory ◽  
Quantum Measurement ◽  
Physical Reality ◽  
Quantum Field ◽  
Quantum Object ◽  
Classical Physics ◽  
Quantum Phenomenon ◽  
Quantum Objects ◽  
Quantum Phenomena

This article reconsiders the concept of physical reality in quantum theory and the concept of quantum measurement, following Bohr, whose analysis of quantum measurement led him to his concept of a (quantum) “phenomenon,” referring to “the observations obtained under the specified circumstances,” in the interaction between quantum objects and measuring instruments. This situation makes the terms “observation” and “measurement,” as conventionally understood, inapplicable. These terms are remnants of classical physics or still earlier history, from which classical physics inherited it. As defined here, a quantum measurement does not measure any preexisting property of the ultimate constitution of the reality responsible for quantum phenomena. An act of measurement establishes a quantum phenomenon by an interaction between the instrument and the quantum object or in the present view the ultimate constitution of the reality responsible for quantum phenomena and, at the time of measurement, also quantum objects. In the view advanced in this article, in contrast to that of Bohr, quantum objects, such as electrons or photons, are assumed to exist only at the time of measurement and not independently, a view that redefines the concept of quantum object as well. This redefinition becomes especially important in high-energy quantum regimes and quantum field theory and allows this article to define a new concept of quantum field. The article also considers, now following Bohr, the quantum measurement as the entanglement between quantum objects and measurement instruments. The argument of the article is grounded in the concept “reality without realism” (RWR), as underlying quantum measurement thus understood, and the view, the RWR view, of quantum theory defined by this concept. The RWR view places a stratum of physical reality thus designated, here the reality ultimately responsible for quantum phenomena, beyond representation or knowledge, or even conception, and defines the corresponding set of interpretations quantum mechanics or quantum field theory, such as the one assumed in this article, in which, again, not only quantum phenomena but also quantum objects are (idealizations) defined by measurement. As such, the article also offers a broadly conceived response to J. Bell’s argument “against ‘measurement’”.

scholarly journals On Determinism, Causality, and Free Will: Contribution from Physics

2021 ◽  
Vol 69 (4) ◽  
pp. 5-24
Author(s):  
Grzegorz Karwasz
Keyword(s):  
Quantum Mechanics ◽  
Free Will ◽  
Recent Article ◽  
Sufficient Conditions ◽  
Human Action ◽  
Human Mind ◽  
Divine Action ◽  
Classical Physics ◽  
The World ◽  
Principle Of Causality

Determinism, causality, chance, free will and divine providence form a class of interlaced problems lying in three domains: philosophy, theology, and physics. Recent article by Dariusz Łukasiewicz in Roczniki Filozoficzne (no. 3, 2020) is a great example. Classical physics, that of Newton and Laplace, may lead to deism: God created the world, but then it goes like a mechanical clock. Quantum mechanics brought some “hope” for a rather naïve theology: God acts in gaps between quanta of indetermination. Obviously, any strict determinism jeopardizes the existence of free will. Yes, but only if human mind follows the laws of physics and only if nothing exists outside the physical limits of space and time. We argue that human action lies in-between two worlds: “earth” and “heavens” using the language of Genesis. In that immaterial world, outside time and space constraints, there is no place for the chain of deterministic events. We discuss, in turn, that the principle of causality, a superior law even in physics, reigns also in the non-material world. Though, determinism in the material universe and causality in both worlds seem to be sufficient conditions, to eliminate “chaotic”, or probabilistic causes from human (and divine) action.

scholarly journals The End of a Classical Ontology for Quantum Mechanics?

Entropy ◽  
2020 ◽  
Vol 23 (1) ◽  
pp. 12
Author(s):  
Peter W. Evans
Keyword(s):  
Quantum Mechanics ◽  
Quantum Theory ◽  
Physical Reality ◽  
Fundamental Ontology ◽  
Hidden Variable ◽  
Variable Approach ◽  
The World ◽  
Obvious Consequence ◽  
The Cost ◽  
Causal Structures

In this paper, I argue that the Shrapnel–Costa no-go theorem undermines the last remaining viability of the view that the fundamental ontology of quantum mechanics is essentially classical: that is, the view that physical reality is underpinned by objectively real, counterfactually definite, uniquely spatiotemporally defined, local, dynamical entities with determinate valued properties, and where typically ‘quantum’ behaviour emerges as a function of our own in-principle ignorance of such entities. Call this view Einstein–Bell realism. One can show that the causally symmetric local hidden variable approach to interpreting quantum theory is the most natural interpretation that follows from Einstein–Bell realism, where causal symmetry plays a significant role in circumventing the nonclassical consequences of the traditional no-go theorems. However, Shrapnel and Costa argue that exotic causal structures, such as causal symmetry, are incapable of explaining quantum behaviour as arising as a result of noncontextual ontological properties of the world. This is particularly worrying for Einstein–Bell realism and classical ontology. In the first instance, the obvious consequence of the theorem is a straightforward rejection of Einstein–Bell realism. However, more than this, I argue that, even where there looks to be a possibility of accounting for contextual ontic variables within a causally symmetric framework, the cost of such an account undermines a key advantage of causal symmetry: that accepting causal symmetry is more economical than rejecting a classical ontology. Either way, it looks like we should give up on classical ontology.

scholarly journals Stable Facts, Relative Facts

2021 ◽  
Vol 51 (1) ◽  
Author(s):  
Andrea Di Biagio ◽  
Carlo Rovelli
Keyword(s):  
Quantum Theory ◽  
Linear Evolution ◽  
Classical World ◽  
The World

AbstractFacts happen at every interaction, but they are not absolute: they are relative to the systems involved in the interaction. Stable facts are those whose relativity can effectively be ignored. In this work, we describe how stable facts emerge in a world of relative facts and discuss their respective roles in connecting quantum theory and the world. The distinction between relative and stable facts resolves the difficulties pointed out by the no-go theorem of Frauchiger and Renner, and is consistent with the experimental violation of the Local Friendliness inequalities of Bong et al.. Basing the ontology of the theory on relative facts clarifies the role of decoherence in bringing about the classical world and solves the apparent incompatibility between the ‘linear evolution’ and ‘projection’ postulates.

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