scholarly journals TEORIA FISICA E SUA REALIFICAZIONE. CASO DI STUDIO: LA CAUSALITÀ

2019 ◽  
Author(s):  
Giacomo Mauro D'Ariano
Keyword(s):  
Quantum Theory ◽  
Joint Probability ◽  
Classical Case ◽  
Causal Connection ◽  
Objective Reality ◽  
Quantum Theories ◽  
Nature Of Time ◽  
Object Ontology ◽  
Block Universe

I will discuss realism of classical and quantum theories, assessing the untenability of the object ontology, and proposing its substitution with the notion of system used in operational theories, notion that represents a theoretical connection between two events. Within operational theories the distinction between theory and objective reality is well defined: the theory provides the mathematical description of systems and events, and predicts the joint probability of the events; objective reality is identified with the collection of events that actually occurred. I then analyse some cases of realification of the theory – namely the fallacy of identifying theory with reality. In particular, the cases of the notion of causality and causal connection between events are analysed, emphasising their purely theoretical nature, contrarily to the widespread connotation of objectivity. I re-establish the role of causality in physics as a theorem of quantum theory, and hence also of classical theory (which is a restriction of quantum theory), showing how it represents a probabilistic generalisation of the same concept used in special relativity, and discussing why such notion may trivialise in the classical case. I end with a critique of David Albert’s Past Hypothesis about the nature of time, and of the resulting Block Universe vision of space-time, to reaffirm Reality of Time.

scholarly journals The quantum theory of time, the block universe, and human experience

2018 ◽  
Vol 376 (2123) ◽  
pp. 20170316 ◽  
Author(s):  
Joan A. Vaccaro
Keyword(s):  
Quantum Theory ◽  
Foundations Of Quantum Mechanics ◽  
Human Experience ◽  
Present Moment ◽  
Ongoing Research ◽  
Physical Universe ◽  
Phenomenological Consequence ◽  
Nature Of Time ◽  
The Universe ◽  
Block Universe

Advances in our understanding of the physical universe have dramatically affected how we view ourselves. Right at the core of all modern thinking about the universe is the assumption that dynamics is an elemental feature that exists without question. However, ongoing research into the quantum nature of time is challenging this view: my recently introduced quantum theory of time suggests that dynamics may be a phenomenological consequence of a fundamental violation of time reversal symmetry. I show here that there is consistency between the new theory and the block universe view. I also discuss the new theory in relation to the human experience of existing in the present moment, able to reflect on the past and contemplate a future that is yet to happen. This article is part of a discussion meeting issue ‘Foundations of quantum mechanics and their impact on contemporary society’.

scholarly journals Causality re-established

2018 ◽  
Vol 376 (2123) ◽  
pp. 20170313 ◽  
Author(s):  
Giacomo Mauro D’Ariano
Keyword(s):  
Quantum Theory ◽  
Classical Theory ◽  
Recent Literature ◽  
Foundations Of Quantum Mechanics ◽  
Classical Case ◽  
The Status ◽  
Interpretation Of Quantum Theory ◽  
False Idea ◽  
Block Universe ◽  
Probabilistic Theories

Causality has never gained the status of a ‘law’ or ‘principle’ in physics. Some recent literature has even popularized the false idea that causality is a notion that should be banned from theory. Such misconception relies on an alleged universality of the reversibility of the laws of physics, based either on the determinism of classical theory, or on the multiverse interpretation of quantum theory, in both cases motivated by mere interpretational requirements for realism of the theory. Here, I will show that a properly defined unambiguous notion of causality is a theorem of quantum theory, which is also a falsifiable proposition of the theory. Such a notion of causality appeared in the literature within the framework of operational probabilistic theories. It is a genuinely theoretical notion, corresponding to establishing a definite partial order among events, in the same way as we do by using the future causal cone on Minkowski space. The notion of causality is logically completely independent of the misidentified concept of ‘determinism’, and, being a consequence of quantum theory, is ubiquitous in physics. In addition, as classical theory can be regarded as a restriction of quantum theory, causality holds also in the classical case, although the determinism of the theory trivializes it. I then conclude by arguing that causality naturally establishes an arrow of time. This implies that the scenario of the ‘block Universe’ and the connected ‘past hypothesis’ are incompatible with causality, and thus with quantum theory: they are both doomed to remain mere interpretations and, as such, are not falsifiable, similar to the hypothesis of ‘super-determinism’. This article is part of a discussion meeting issue ‘Foundations of quantum mechanics and their impact on contemporary society’.

Physics, Time, and Qualia

2021 ◽  
Vol 28 (9) ◽  
pp. 36-51
Author(s):  
M. Cortes ◽  
L. Smolin
Keyword(s):  
Quantum Theory ◽  
Quantum Gravity ◽  
Conscious Awareness ◽  
The World ◽  
Quantum Event ◽  
Nature Of Time

We suggest that four of the deepest problems in science are closely related and may share a common resolution. These are (1) the foundational problems in quantum theory, (2) the problem of quantum gravity, (3) the role of qualia and conscious awareness in nature, (4) the nature of time. We begin by proposing an answer to the question of what a quantum event is: an event is a process in which an aspect of the world which has been indefinite becomes definite. We build from this an architecture of the world in which qualia are real and consequential and time is active, fundamental, and irreversible.

Fundamentality

2017 ◽  
Author(s):  
Richard Healey
Keyword(s):  
Quantum Theory ◽  
High Energy Physics ◽  
Physical Property ◽  
Natural World ◽  
High Energy ◽  
Quantum Field Theories ◽  
Fundamental Physics ◽  
The World ◽  
Energy Physics

The metaphor that fundamental physics is concerned to say what the natural world is like at the deepest level may be cashed out in terms of entities, properties, or laws. The role of quantum field theories in the Standard Model of high-energy physics suggests that fundamental entities, properties, and laws are to be sought in these theories. But the contextual ontology proposed in Chapter 12 would support no unified compositional structure for the world; a quantum state assignment specifies no physical property distribution sufficient even to determine all physical facts; and quantum theory posits no fundamental laws of time evolution, whether deterministic or stochastic. Quantum theory has made a revolutionary contribution to fundamental physics because its principles have permitted tremendous unification of science through the successful application of models constructed in conformity to them: but these models do not say what the world is like at the deepest level.

scholarly journals The Invariant Set Postulate: a new geometric framework for the foundations of quantum theory and the role played by gravity

2009 ◽  
Vol 465 (2110) ◽  
pp. 3165-3185 ◽  
Author(s):  
T. N. Palmer
Keyword(s):  
Quantum Theory ◽  
Science Fiction ◽  
State Space ◽  
Fractal Geometry ◽  
Quantum Physics ◽  
Nonlinear Dynamical Systems ◽  
Physical Reality ◽  
Invariant Set ◽  
Geometric Framework

A new law of physics is proposed, defined on the cosmological scale but with significant implications for the microscale. Motivated by nonlinear dynamical systems theory and black-hole thermodynamics, the Invariant Set Postulate proposes that cosmological states of physical reality belong to a non-computable fractal state-space geometry I , invariant under the action of some subordinate deterministic causal dynamics D I . An exploratory analysis is made of a possible causal realistic framework for quantum physics based on key properties of I . For example, sparseness is used to relate generic counterfactual states to points p ∉ I of unreality, thus providing a geometric basis for the essential contextuality of quantum physics and the role of the abstract Hilbert Space in quantum theory. Also, self-similarity, described in a symbolic setting, provides a possible realistic perspective on the essential role of complex numbers and quaternions in quantum theory. A new interpretation is given to the standard ‘mysteries’ of quantum theory: superposition, measurement, non-locality, emergence of classicality and so on. It is proposed that heterogeneities in the fractal geometry of I are manifestations of the phenomenon of gravity. Since quantum theory is inherently blind to the existence of such state-space geometries, the analysis here suggests that attempts to formulate unified theories of physics within a conventional quantum-theoretic framework are misguided, and that a successful quantum theory of gravity should unify the causal non-Euclidean geometry of space–time with the atemporal fractal geometry of state space. The task is not to make sense of the quantum axioms by heaping more structure, more definitions, more science fiction imagery on top of them, but to throw them away wholesale and start afresh. We should be relentless in asking ourselves: From what deep physical principles might we derive this exquisite structure? These principles should be crisp, they should be compelling. They should stir the soul. Chris Fuchs ( Gilder 2008 , p. 335)

II. Your Present Moment in Spacetime

2021 ◽  
Vol 2021 (06) ◽  
pp. 0626
Author(s):  
Conrad Dale Johnson
Keyword(s):  
Quantum Physics ◽  
Distributed Processing ◽  
Processing System ◽  
Physical World ◽  
Measuring Instruments ◽  
Present Moment ◽  
Local Measurement ◽  
Hyperbolic Structure ◽  
Objective Reality ◽  
Block Universe

This essay extends the argument begun in "Why Quantum Mechanics Makes Sense," exploring the conditions under which a physical world can define and communicate information. I argue that like the structure of quantum physics, the principles of Special and General Relativity can be understood as reflecting the requirements of a universe in which things are observable and measurable. I interpret the peculiar hyperbolic structure of spacetime not as the static, four-dimensional geometry of an unobservable "block universe", but as the background metric of an evolving web of communicated information that we, along with all our measuring instruments and recording devices, actually experience in our local "here and now." Our relativistic universe is conceived as a parallel distributed processing system, in which a common objective reality is constantly being woven out of many kinds of facts determined separately in countless local measurement-contexts.

Consequence and ‘Cause’: Thirteenth-Century Reflections on the Nature of Consequences

Vivarium ◽  
2018 ◽  
Vol 56 (3-4) ◽  
pp. 320-339
Author(s):  
Joke Spruyt
Keyword(s):  
Thirteenth Century ◽  
Causal Connection ◽  
Fundamental Feature ◽  
Functional Characterisation ◽  
Henry Of Ghent

Abstract Thirteenth-century views on consequences have not yet received much attention. Authors of this period deserve closer scrutiny, because of their profound interest in the nature of consequence. The fundamental feature of a consequence was captured in the claim that its antecedent is the cause of its consequent. At the same time authors systematically discussed consequences in terms of truth-preservation. This paper considers the requirements of syllogistic argument and consequences in general, including the role of ‘cause’ in the identification of syllogisms proper, looks at different descriptions of consequence, moves on to discussions of the syncategorema ‘si’ – in syncategoremata treatises by Peter of Spain, Henry of Ghent, Nicholas of Paris and William of Sherwood, as well as some sophismata tracts – and explores what thirteenth-century authors make of the truth-functional characterisation of consequence, showing how it clashes with the authors’ insistence on a causal connection between antecedent and consequent.

Subsequent and Subsidiary? Rethinking the Role of Applications in Establishing Quantum Mechanics

2015 ◽  
Vol 45 (5) ◽  
pp. 641-702 ◽  
Author(s):  
Jeremiah James ◽  
Christian Joas
Keyword(s):  
Molecular Structure ◽  
Quantum Mechanics ◽  
Quantum Theory ◽  
Classical Mechanics ◽  
Theory Construction ◽  
Science Pedagogy ◽  
Old Quantum Theory ◽  
The Common ◽  
Complete Quantum

As part of an attempt to establish a new understanding of the earliest applications of quantum mechanics and their importance to the overall development of quantum theory, this paper reexamines the role of research on molecular structure in the transition from the so-called old quantum theory to quantum mechanics and in the two years immediately following this shift (1926–1928). We argue on two bases against the common tendency to marginalize the contribution of these researches. First, because these applications addressed issues of longstanding interest to physicists, which they hoped, if not expected, a complete quantum theory to address, and for which they had already developed methods under the old quantum theory that would remain valid under the new mechanics. Second, because generating these applications was one of, if not the, principal means by which physicists clarified the unity, generality, and physical meaning of quantum mechanics, thereby reworking the theory into its now commonly recognized form, as well as developing an understanding of the kinds of predictions it generated and the ways in which these differed from those of the earlier classical mechanics. More broadly, we hope with this article to provide a new viewpoint on the importance of problem solving to scientific research and theory construction, one that might complement recent work on its role in science pedagogy.

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