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arXiv2016

Pragmatic Information in Quantum Mechanics

An objective definition of pragmatic information and the consideration of recent results about information processing in the human brain can help overcome some traditional difficulties with the interpretation of quantum mechanics. Rather than attempting to define information ab initio, I introduce the concept of interaction between material bodies as a primary concept. Two distinct categories can be identified: 1) Interactions which can always be reduced to a superposition of physical interactions (forces) between elementary constituents; 2) Interactions between complex bodies which cannot be reduced to a superposition of interactions between parts, and in which patterns and forms (in space and/or time) play the determining role. Pragmatic information is then defined as the correspondence between a given pattern and the ensuing pattern-specific change. I will show that pragmatic information is a biological concept that plays no active role in the purely physical domain; it only does so when a living organism intervenes. The consequences for the foundations of both classical and quantum physics are important and will be discussed in detail. Since by its very definition pragmatic information (the one our brain uses to represent, think about and react to the outside world)cannot operate in the quantum domain, it is advisable to refrain from using it in our mental representation of what is happening 'inside' a quantum system. Although the theoretical framework developed for quantum mechanics handles mathematical entities specifically attributed to a quantum system, the only truly pragmatic information it can provide relates to macroscopic effects on the environment (natural, or artificial as in a measurement instrument) with which the system interacts.

physics.hist-ph↗

arXiv2015

Randomness: quantum versus classical

Recent tremendous development of quantum information theory led to a number of quantum technological projects, e.g., quantum random generators. This development stimulates a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is elaboration of a consistent and commonly accepted interpretation of quantum state. Closely related problem is clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. The second part of this review is devoted to the information interpretation of quantum mechanics (QM) in the spirit of Zeilinger and Brukner (and QBism of Fuchs et al.) and physics in general (e.g., Wheeler's "it from bit") as well as digital philosophy of Chaitin (with historical coupling to ideas of Leibnitz). Finally, we continue discussion on interrelation of quantum and classical randomness and information interpretation of QM.

quant-ph↗

arXiv2016

Local Causality, Probability and Explanation

In papers published in the 25 years following his famous 1964 proof John Bell refined and reformulated his views on locality and causality. Although his formulations of local causality were in terms of probability, he had little to say about that notion. But assumptions about probability are implicit in his arguments and conclusions. Probability does not conform to these assumptions when quantum mechanics is applied to account for the particular correlations Bell argues are locally inexplicable. This account involves no superluminal action and there is even a sense in which it is local, but it is in tension with the requirement that the direct causes and effects of events are nearby.

quant-ph↗

arXiv2017

A strict epistemic approach to physics

The general view is that all fundamental physical laws should be formulated within the framework given by quantum mechanics (QM). In a sense, QM therefore has the character of a metaphysical theory. Consequently, if it is possible to derive QM from more basic principles, these principles should be of general, philosophical nature. Here, we derive the formalism of QM from well-motivated epistemic principles. A key assumption is that a physical theory that relies on entities or distinctions that are unknowable in principle gives rise to wrong predictions. First, an epistemic formalism is developed, using concepts like knowledge and potential knowledge, identifying a physical state $S$ with the potential knowledge of the physical world. It is demonstrated that QM emerges from this formalism. However, Hilbert spaces, wave functions and probabilities are defined in certain well-defined observational contexts only. This means that the epistemic formalism is broader than QM. In the fundamental layer of description, the physical state $S$ is a subset of a state space $\mathcal{S}=\{Z\}$, such that $S$ always contains many elements $Z$. These elements correspond to unattainable states of complete knowledge of the world. The evolution of $S$ cannot be determined in terms of the individual evolution of the elements $Z$, unlike the evolution of an ensemble in classical phase space. The evolution of $S$ is described in terms of sequential time $n\in \mathbf{\mathbb{N}}$, which is updated according to $n\rightarrow n+1$ each time an event occurs, each time potential knowledge changes. Sequential time $n$ can be separated from relational time $t$, which describes distances between events in space-time. There is an entire space-time associated with each $n$, in which $t$ represents the knowledge at sequential time $n$ about the temporal relations between present and past events.

quant-ph↗

arXiv2018

Solution of the Mayan Calendar Enigma

The Mayan calendar is proposed to derive from an arithmetical model of naked-eye astronomy. The Palenque and Copan lunar equations, used during the Maya Classic period (200 to 900 AD) are solution of the model and the results are expressed as a function of the Xultun numbers, four enigmatic Long Count numbers deciphered in the Maya ruins of Xultun, dating from the IX century AD, providing strong arguments in favor of the use of the model by the Maya. The different Mayan Calendar cycles can be derived from this model and the position of the Calendar Round at the mythical date of creation 13(0).0.0.0.0 4 Ahau 8 Cumku is calculated. This study shows the high proficiency of Mayan mathematics as applied to astronomy and timekeeping for divinatory purposes.

math.HO↗

arXiv2016

Astronomy and landscape at the prehistoric settlement Villaggio dei Faraglioni, Ustica, Sicily

The placement of the Middle Bronze Age settlement Villaggio dei Faraglioni on the Ustica island, one of the best preserved prehistoric village of the Mediterranean area, is analyzed from a cognitive point of view, taking into account archaeoastronomy and landscape archaeology aspects. It turns out that the place might have been selected because of its privileged position with respect to the landscape, better than conforming to utilitarian/defensive considerations, as instead occurs for contemporary, for instance Mycenaean, sites. From the village it was indeed possible to follow the rising and setting of the sun in the months close to the winter solstice on the two elevated peaks existing on the opposite side of the island, in a symmetric way. As a consequence, the inhabitants could determine the day of the winter solstice with an approximation of a few days, using this partial calendar for agricultural and navigational purposes. A possible astronomical orientation of the urban layout is also analyzed

physics.hist-ph↗

arXiv2016

Why trust a theory? Some further remarks (part 1)

I expand on some ideas from my recent review "String theory to the rescue," I discuss my use of Bayesian reasoning. I argue that it can be useful but that it is very far from the central point of the discussion. I then review my own personal history with the multiverse. Finally I respond to some of the criticisms of Ellis and Silk, which initiated this interesting discussion.

hep-th↗

arXiv2016

On operational approach to entanglement and how to certify it

Entangled physical systems are an important resource in quantum information. Some authors claim that in fact all quantum states are entangled. In this paper we show that this claim is incorrect and we discuss in operational way differences existing between separable and entangled states. A sufficient condition for entanglement is the violation of Bell- CHSH-CH inequalities and/or steering inequalities. Since there exist experiments outside the domain of quantum physics violating these inequalities therefore in the operational approach one cannot say that the entanglement is an exclusive quantum phenomenon. We also explain that an unambiguous experimental certification of the entanglement is a difficult task because classical statistical significance tests may not be trusted if sample homogeneity cannot be tested or is not tested carefully enough.

quant-ph↗

arXiv2016

Minkowski and Special Relativity: Does His Spacetime Geometry Explain Space Contraction?

For over a century Minkowskian spacetime has dominated discussions of space contraction and time dilation within special relativity. Brown and Pooley have called into question both the assumptions of Minkowski and the effects his presumed spacetime has upon objects in motion. But while they reject Minkowski, Brown and Pooley do not fill in the missing causal connection between velocity and space contraction and time dilation. To supply this causal connection between object and observer in relative motion we should be focusing on energy difference rather than velocity difference. When different inertial observers at different relative velocities measure the same rod (or clock), each observer registers a different amount of kinetic energy for the object. Following the consequences of this permits a new understanding of relativistic space contraction and time dilation.

physics.hist-ph↗

arXiv2017

Quantum Superpositions and the Representation of Physical Reality Beyond Measurement Outcomes and Mathematical Structures

In this paper we intend to discuss the importance of providing a physical representation of quantum superpositions which goes beyond the mere reference to mathematical structures and measurement outcomes. This proposal goes in the opposite direction to the project present in orthodox contemporary philosophy of physics which attempts to "bridge the gap" between the quantum formalism and common sense "classical reality" --precluding, right from the start, the possibility of interpreting quantum superpositions through non-classical notions. We will argue that in order to restate the problem of interpretation of quantum mechanics in truly ontological terms we require a radical revision of the problems and definitions addressed within the orthodox literature. On the one hand, we will discuss the need of providing a formal redefinition of superpositions which captures explicitly their contextual character. On the other hand, we will attempt to replace the focus on the measurement problem, which concentrates on the justification of measurement outcomes from "weird" superposed states, and introduce the superposition problem which focuses instead on the conceptual representation of superpositions themselves. In this respect, after presenting three necessary conditions for objective physical representation, we will provide arguments which show why the classical (actualist) representation of physics faces severe difficulties to solve the superposition problem. Finally, we will also argue that, if we are willing to abandon the (metaphysical) presupposition according to which 'Actuality = Reality', then there is plenty of room to construct a conceptual representation for quantum superpositions.

quant-ph↗

arXiv2018

Stirling Stuff

Robert Stirling's patent for what was essentially a new type of engine to create work from heat was submitted in 1816. Its reception was underwhelming and although the idea was sporadically developed, it was eclipsed by the steam engine and, later, the internal combustion engine. Today, though, the environmentally favourable credentials of the Stirling engine principles are driving a resurgence of interest, with modern designs using modern materials. These themes are woven through a historically based narrative that introduces Robert Stirling and his background, a description of his patent and the principles behind his engine, and discusses the now popular model Stirling engines readily available. These topical models, or alternatives made 'in house', form a good platform for investigating some of the thermodynamics governing the performance of engines in general.

physics.hist-ph↗

arXiv2016

Archaeoastronomy in the Khmer heartland

The heartland of the Khmer empire is literally crowded by magnificent monuments built in the course of many centuries. These monuments include the world-famous state-temples, such as Angkor Wat, but also many other temples and huge water reservoirs. Using Google Earth data as well as GIS data and reconstructing the ancient sky with Stellarium, we investigate here on the relationships of astronomy with orientation and topography in a systematic fashion, following the methods of modern Archaeoastronomy and strictly keeping at a bay vague or esoteric proposals put forward by many authors in the past. As a result, a very clear pattern of cardinal orientation and alignment arises, connected with the temple's symbolism and the management of power by the Khmer kings. As a bonus, the comparison with the Angkor monuments allows to put forward a explanation for the anomalous orientation of the unique two peripheral state temples of Cambodia.

physics.hist-ph↗

arXiv2019

Hawking Radiation and Analogue Experiments: A Bayesian Analysis

We present a Bayesian analysis of the epistemology of analogue experiments with particular reference to Hawking radiation. First, we prove that such experiments can be confirmatory in Bayesian terms based upon appeal to 'universality arguments'. Second, we provide a formal model for the scaling behaviour of the confirmation measure for multiple distinct realisations of the analogue system and isolate a generic saturation feature. Finally, we demonstrate that different potential analogue realisations could provide different levels of confirmation. Our results provide a basis both to formalise the epistemic value of analogue experiments that have been conducted and to advise scientists as to the respective epistemic value of future analogue experiments.

physics.hist-ph↗

arXiv2016

The infinite turn and speculative explanations in cosmology

Infinity, in various guises, has been invoked recently in order to `explain' a number of important questions regarding observable phenomena in science, and in particular in cosmology. Such explanations are by their nature speculative. Here we introduce the notions of relative infinity, closure, and economy of explanation and ask: to what extent explanations involving relative or real constructed infinities can be treated as reasonable?

physics.hist-ph↗

arXiv2016

Towards better understanding of QBism

Recently I posted a paper entitled "External observer reflections on QBism". As any external observable, I was not able to reflect some features of QBism properly. Therefore comments which I received from one of its creators, C. Fuchs, are very valuable - to understand better the views of QBists. Some of QBism features are very delicate and to extract them from articles of QBists is not a simple task. Therefore I hope that the second portion of my reflection on QBism (or better to say my reflections on Fuchs' reflections on my reflections) might be interesting and useful for other experts in quantum foundations and quantum information theory (especially by taking into account my previous aggressively anti-QBism position). In the present paper I correct some of my previously posted critical comments on QBism. At the same time better understanding of QBists views on some problems leads to improvement and strengthening of other critical comments.

quant-ph↗

arXiv2016

Nature's Book Keeping System

Establishing how one should describe and study natures fundamental degrees of freedom is a notoriously difficult problem. It is tempting to assume that the number of bits (or qubits) needed in a given Planckian 3-volume, or perhaps 2-volume, is a fixed finite number, but this ansatz does not make the problem much easier. We come not even close to solving this problem, but we propose various ingredients in phrasing the questions, possibilities and limitations that may serve as starting points.

hep-th↗

arXiv2016

The future's not ours to see

An account of determinism and indeterminism in physics, addressed to non-physicist readers, leading up to proposals for how to understand statements about the future and single-event probability, motivated by quantum mechanics.

physics.hist-ph↗

arXiv2016

The Ancient Astronomy of Easter Island: Mars and Sweet Potatoes

The role of the monument Moai a Mata Mea at Easter Island in the fertility cult has been explained. The own late statue that belonged to the ruling Miru group can provisionally be dated back to ca. 1691 A.D. on the backbone of the archaeoastronomical studies as well as the written sources. Some data about watchings of the total solar eclipse of September 16, 1773 A.D. and Halley's Comet of 1682 A.D. are presented as well. A new information on the early settlement of Rapanui is of our interest, too.

physics.hist-ph↗