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arXiv2019

The Relativistic Transactional Interpretation: Immune to the Maudlin Challenge

The Transactional Interpretation has been subject at various times to a challenge based on a type of thought experiment first proposed by Maudlin. It has been argued by several authors that such experiments do not in fact constitute a significant problem for the transactional picture. The purpose of this work is to point out that, when the relativistic level of the interpretation is considered, Maudlin-type challenges cannot even be mounted, since the putative 'slow-moving offer wave,' taken as subject to contingent confirmation, does not exist. This is a consequence of the Davies relativistic quantum-mechanical version of the direct-action theory together with the asymmetry between fermionic field sources and bosonic fields. The Maudlin challenge therefore evaporates completely when the relativistic level of the theory is taken into account.

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arXiv2017

Galileo (1564-1642) and Kepler (1571-1630): the modern scientist and the mystic

The art of advertising one's scientific achievements, of which Galileo was an early master, is a trademark of successful modern science. Dedicated believers and mystics of science, such as Kepler, are less popular. Yet, an alleged rigorous rationalist like Wolfgang Pauli found in his later troubled life a kinship to Kepler's "archetypal ideas".

physics.hist-ph↗

arXiv2017

Time in the theory of relativity: inertial time, light clocks, and proper time

In a way similar to classical mechanics where we have the concept of inertial time as expressed in the motions of bodies, in the (special) theory of relativity we can regard the inertial time as the only notion of time at play. The inertial time is expressed also in the propagation of light. This gives rise to a notion of clock, the light clock, which we can regard as a notion derived from the inertial time. The light clock can be seen as a solution of the theory, which complies with the requirement that a clock to be so must have a rate that is independent of its past history. Contrary to Einstein's view, we do not need the concept of clock as an independent concept. This implies, in particular, that we do not need to rely on the notions of atomic clock or atomic time in the theory of relativity.

physics.hist-ph↗

arXiv2016

The Ancient Astronomy of Easter Island: Aldebaran and the Pleiades

There is a good cause to assert that the Easter Islanders constantly watched Aldebaran and the Pleiades in the past. The Russian scholar Irina K. Fedorova and the American scholar Georgia Lee were the first who contributed significantly to the archaeoastronomical studies of these celestial bodies. I have decoded the Mataveri calendar completely. The ceremonial platform Hekii 2 was oriented on Aldebaran and nearby stars. The disappearance of the Pleiades during the dawn period in the north at the end of August could be an important mark before the arrival of sooty terns and before the elections of the next bird-man. The calculated dates of several solar eclipses have been used for composing the chronology of Easter Island from 1771 till 1867 A.D.

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arXiv2016

The theory of the Double Solution: Dynamical issues in quantum systems in the semiclassical regime

The "dynamical mismatch" observed in quantum systems in the semiclassical regime challenge the Pilot wave model. Indeed the dynamics and properties of such systems depend on the trajectories of the classically equivalent system, whereas the de Broglie-Bohm trajectories are generically non-classical.\ In this work we examine the situation for the model favoured by de Broglie, the theory of the Double Solution (DS). We will see that the original DS model applied to semiclassical systems is also prone to the dynamical mismatch.\ However we will argue that the DS theory can be modified in order to yield propagation of the singularity in accord with the underlying classical dynamics of semiclassical systems.

quant-ph↗

arXiv2016

What do we learn from computer simulations of Bell experiments?

Contrary to counterfactual definiteness quantum theory teaches us that measuring instruments are not passively reading predetermined values of physical observables. Counterfactual definiteness allows proving Bell inequalities. If the contextual character of quantum measurements is correctly taken into account the proofs of these inequalities may not be done. In recent computer simulations of idealized Bell experiment predetermined successive outcomes of measurements for each setting and predetermined time delays of their registrations are calculated. Time windows and time delays are used to select various samples. Correlations, estimated using these selected samples are consistent with the predictions of quantum theory and the time window dependence is similar to the dependence observed in some real experiments. It is an important example how correlations can be explained without evoking quantum non-locality. However by using a suitable post-selection one may prove anything. Since before the post-selection generated samples may not violate Bell inequalities as significantly as finite samples generated using quantum predictions thus one may not conclude that counterfactual definiteness is not able to distinguish classical from quantum physics. Moreover we show that for each choice of a time window there exists a contextual hidden variable probabilistic model consistent with the post-selection procedure used by the authors what explains why they are able to reproduce quantum predictions.

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arXiv2016

Matching the Unmatchable. Complexity Theory and Quantum Theory

This is a philosophical paper. It claims that there is a gap to be filled in the relationship between complexity theory (CT) and quantum theory (QT). This gap concerns two very distinct understandings of time. The paper provides the ground for filling up such gap. Indeed, most works on complexity at large focus on the macroscopic world, leaving behind the importance of the microscopic world. This paper specifies what both worlds consist of, and argues that a solid account of the world, i.e. complexity, must necessarily take into account both dimensions of reality.

physics.hist-ph↗

arXiv2016

Collapse or no collapse? What is the best ontology of quantum mechanics in the primitive ontology framework?

Recalling the state of the art in the interpretation of quantum physics, this paper emphasizes that one cannot simply add a collapse parameter to the SchrÃ¶dinger equation in order to solve the measurement problem. If one does so, one is also committed to a primitive ontology of a configuration of matter in physical space in order to have something in the ontology that constitutes the determinate measurement outcomes. The paper then argues that in the light of this consequence, the collapse postulate loses its attractiveness in comparison to an ontology of persisting particles moving on continuous trajectories according to a deterministic law.

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arXiv2016

Against free will in the contemporary natural sciences

The claim of the freedom of the will (understood as an individual who is transcendent to Nature) in the name of XXth century scientific knowledge, against the perspective of XVIIIth-XIXth century scientific materialism, is analysed and refuted in the present paper. The hypothesis of reductionism finds no obstacle within contemporary natural sciences. Determinism in classical physics is irrefutable, unless classical physics is itself refuted. From quantum mechanics, some authors argue that free will is possible because there is an ontological indeterminism in the natural laws, and that the mind is responsible for the wave function collapse of matter, which leads to a choice among the different possibilities for the body. However, here I defend the opposite thesis because indeterminism does not imply free will, and because the considerations about an autonomous mind sending orders to the body is against neuroscience or evolutionary theories about human beings. The quantum theory of measurement can be interpreted without the intervention of human minds, but other fields of science cannot contemplate the mentalist scenario. A fatalistic or materialist view, which denies the possibility of a free will, makes much more sense in scientific terms.

physics.hist-ph↗

arXiv2016

The golden age of Calcutta physics: Difficulties in reconstructing the history

Classes started in the newly established Physics Department of Calcutta University Science College in 1916. Raman, Bose and Saha were three young members of the small physics faculty consisting of barely half a dozen faculty members. Within about one decade, three extraordinary discoveries came from these young men---Saha ionization equation in 1920, Bose statistics in 1924, Raman effect in 1928. However, fortunes of Calcutta University quickly got intertwined with India's freedom struggle led by Mahatma Gandhi exactly at the same time and the physics group got tragically disrupted. Indian physics never succeeded in reaching that height again. This paper discusses the difficulties in reconstructing a critical history of this Calcutta school of physics during the very short epoch of unmatched brilliance.

physics.hist-ph↗

arXiv2017

The Ancient Astronomy of Easter Island: The Mamari Tablet Tells (Part 1)

The ancient priest-astronomers constantly watched many heavenly bodies. The record about Halley's Comet of 1682 A.D. has been decoded completely. Good agreement between it and the results of European astronomers is seen. The records about Halley's Comet of 1835 A.D. as well as about the sun, the moon, Mars and Saturn have been deciphered as well. The obtained information is the basis in order to understand some aspects of the bird-man cult.

physics.hist-ph↗

arXiv2017

The Reception of the Copernican Revolution Among Provençal Humanists of the Sixteenth and Seventeenth Centuries

We discuss the reception of Copernican astronomy by the Provençal humanists of the XVIth-XVIIth centuries, beginning with Michel de Montaigne who was the first to recognize the potential scientific and philosophical revolution represented by heliocentrism. Then we describe how, after Kepler's Astronomia Nova of 1609 and the first telescopic observations by Galileo, it was in the south of France that the New Astronomy found its main promotors with the humanists and "amateurs éclairés", Nicolas-Claude Fabri de Peiresc and Pierre Gassendi. The professional astronomer Jean-Dominique Cassini, also from Provence, would later elevate the field to new heights in Paris.

physics.hist-ph↗

arXiv2017

Ockham's razor and the interpretations of quantum mechanics

Ockham's razor is a heuristic concept applied in philosophy of science to decide between two or more feasible physical theories. Ockham's razor operates by deciding in favour of the theory with least assumptions and concepts; roughly speaking, the less complex theory. Could Ockham's razor not easily treat the different interpretations as theories and decide in favour of the one with fewest assumptions? We provide an answer to this question by means of examples of applications in literature and the discussion of its historical origin. We review the historical context of Ockham's razor and its connection to medieval philosophical struggles, discuss the essence of its parsimonious core and put it in relation with modern struggles in the context of interpretational issues in Quantum Mechanics. Due to the lack of experimental evidences in string theory, a new field of modern heuristics arose in the last years. We will discuss these heuristics in the context of Ockham-related heuristic methods and analyse the connection of these heuristics with the interpretations of Quantum Mechanics.

quant-ph↗

arXiv2017

Conservation, Inertia, and Spacetime Geometry

As Harvey Brown emphasizes in his book Physical Relativity, inertial motion in general relativity is best understood as a theorem, and not a postulate. Here I discuss the status of the "conservation condition", which states that the energy-momentum tensor associated with non-interacting matter is covariantly divergence-free, in connection with such theorems. I argue that the conservation condition is best understood as a consequence of the differential equations governing the evolution of matter in general relativity and many other theories. I conclude by discussing what it means to posit a certain spacetime geometry and the relationship between that geometry and the dynamical properties of matter.

physics.hist-ph↗

arXiv2017

Enhanced Quantization: The Right way to Quantize Everything

Canonical quantization relies on Cartesian, canonical, phase-space coordinates to promote to Hermitian operators, which also become the principal ingredients in the quantum Hamiltonian. While generally appropriate, this procedure can also fail, e.g., for covariant, quartic, scalar fields in five-and-more spacetime dimensions (and possibly four spacetime dimensions as well), which become trivial; such failures are normally blamed on the `problem' rather than on the 'quantization procedure'. In Enhanced Quantization the association of $c$-numbers to $q$-numbers is chosen very differently such that: (i) there is no need to seek classical, Cartesian, phase-space coordinates; (ii) every classical, contact transformation is applicable and no change of the quantum operators arises; (iii) a new understanding of the importance of 'Cartesian coordinates' is established; and (iv) although discussed elsewhere in detail, the procedures of enhanced quantization offer fully acceptable solutions yielding non-trivial results for quartic scalar fields in four-and-more spacetime dimensions. In early sections, this paper offers a wide-audience approach to the basic principles of Enhanced Quantization using simple examples; later, several significant examples are cited for a deeper understanding. An historical note concludes the paper.

quant-ph↗

arXiv2017

Fundamental Theories and Epistemic Shifts: Can History of Science Serve as a Guide?

The present discussion concerning certain fundamental physical theories (such as string theory and multiverse cosmology) has reopened the demarcation problem between science and non-science. While parts of the physics community see the situation as a beginning epistemic shift in what defines science, others deny that the traditional criterion of empirical testability can or should be changed. As demonstrated by the history of physics, it is not the first time that drastic revisions of theory assessment have been proposed. Although historical reflection has little to offer modern physicists in a technical sense, it does offer a broader and more nuanced perspective on the present debate. This paper suggests that history of science is of some indirect value to modern physicists and philosophers dealing with string theory, multiverse scenarios, and related theoretical ideas.

physics.hist-ph↗

arXiv2017

Emergence and Reductionism: an awkward Baconian alliance

This article discusses the relationship between emergence and reductionism from the perspective of a condensed matter physicist. Reductionism and emergence play an intertwined role in the everyday life of the physicist, yet we rarely stop to contemplate their relationship: indeed, the two are often regarded as conflicting world-views of science. I argue that in practice, they compliment one-another, forming an awkward alliance in a fashion envisioned by the Renaissance scientist, Francis Bacon. Looking at the historical record in classical and quantum physics, I discuss how emergence fits into a reductionist view of nature. Often, a deep understanding of reductionist physics depends on the understanding of its emergent consequences. Thus the concept of energy was unknown to Newton, Leibnitz, Lagrange or Hamilton, because they did not understand heat. Similarly, the understanding of the weak force awaited an understanding of the Meissner effect in superconductivity. Emergence can thus be likened to an encrypted consequence of reductionism. Taking examples from current research, including topological insulators and strange metals, I show that the convection between emergence and reductionism continues to provide a powerful driver for frontier scientific research, linking the lab with the cosmos.

physics.hist-ph↗

arXiv2017

The Ancient Astronomy of Easter Island: The Mamari Tablet Tells (Part 2)

The beginning of the calendar record inscribed on the Mamari tablet has been dated to the day of the summer solstice of December 20, 1680 A.D. The moon was not visible earlier at night. Because of a possible solar eclipse it was a perilous day, a precursor of the future misfortunes: the motion of Halley's Comet of 1682 A.D. and the rebellion of the western tribes. The new data about the watchings of the star Antares have been obtained, too.

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