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1

Neurčité situace a logika

100%

Dvořák P.

Filosofický časopis (Philosophical Journal)

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2015

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vol. 63

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issue 3, Special No: Sedmkrát z logiky a metodologie vědy

9-38

EN

The article surveys and evaluates various approaches to the logic of indeterminate situations. Two types of such situations are discussed: future contingents and quantum indeterminacy. Approaches differ according to whether they can salvage (i) classical tautologies (such as the law of excluded middle) as logical truths, (ii) bivalence and (iii) truth-functionality. What I call “the first solution” denies bivalence and either saves classical logical truths (supervaluations) or truth-functionality (multi-valued approach), but not both. The so-called “second solution”, saving all aforementioned features, harbors difficulties for the contingency of future contingents and is inapplicable in the quantum realm. Finally, the third solution saves bivalence but, at least in the case of quantum logic, abandons truth-functionality.

2

No-signaling in topos formulation and a common ontological basis for classical and non-classical physical theories

100%

Kuś M.

Zagadnienia Filozoficzne w Nauce

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2020

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issue 69

129-143

EN

Starting from logical structures of classical and quantum mechanics we reconstruct the logic of so-called no-signaling theories, where the correlations among subsystems of a composite system are restricted only by a simplest form of causality forbidding an instantaneous communication. Although such theories are, as it seems, irrelevant for the description of physical reality, they are helpful in understanding the relevance of quantum mechanics. The logical structure of each theory has an epistemological flavor, as it is based on analysis of possible results of experiments. In this note we emphasize that not only logical structures of classical, quantum and no-signaling theory may be treated on the same ground but it is also possible to give to all of them a common ontological basis by constructing a “phase space” in all cases. In non-classical cases the phase space is not a set, as in classical theory, but a more general object obtained by means of category theory, but conceptually it plays the same role as the phase space in classical physics.

3

Is Schrödinger's cat dead oa alive?

88%

Grygiel W.

Zagadnienia Filozoficzne w Nauce

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2005

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issue 37

119-139

PL

The Schrödinger's Cat paradox was proposed in 1935 by Edwin Schrodinger, one of the founders of quantum mechanics, as an attempt to visualize the macroscopic realization of a quantum superposition state. A cat is placed in a sealed box together with a vial of poison. A two-state particle (e.g. an electron) is sent into a detector in the box resulting either in a broken or an intact vial and a dead or live cat, respectively. The main problem consists in whether the superposition state of a microscopic particle can be transferred upon the macroscopic cat, that is, whether the cat can exist in a superposition state, being simultaneously dead and alive. Since the standard Copenhagen interpretation is unable to assign any reality to the quantum superposition state, the paradox finds no resolution within the regime of this interpretation. Von Neumann's insistence on the uniform treatment of both microscopic (quantum) and macroscopic (classical) objects according to the laws of quantum mechanics provides a more consistent framework for the resolution of the paradox. In particular, the discovery of the phenomenon of decoherence, whereby the disappearance of the quantum interferences at the macro level is accounted for, suggests the onset of an extremely efficient interference relaxation process (10-23 s) upon the interaction of the two state particle with the detector. As a result, Schrodinger's cat can exist macroscopically either as dead or alive and never as a combination of both. Decoherence not only aids the resolution of the Schrodinger's Cat paradox but also sheds light upon the mechanisms by which the macro-world emerges from the microscopic quantum realm.

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2 Zagadnienia Filozoficzne w Nauce

1 Filosofický časopis (Philosophical Journal)

1 Dvořák P.

1 Grygiel W.

1 Kuś M.

1 2020

1 2015

1 2005

Neurčité situace a logika

No-signaling in topos formulation and a common ontological basis for classical and non-classical physical theories

Is Schrödinger's cat dead oa alive?