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arXiv2019

Sacred Landscape of the Incas in Central Chile: Radial Ceque System Encoded in the Archeological Site Ruinas de Chada

Mounts and hills played a predominant role in all pre-Hispanic Andean cultures, especially for the Inca culture. Through the use of georeferenced orthophotography, we found that the Inca site, Ruinas de Chada, represents the origin of a radial ceque system with alignments connecting, at one end high peaks of mounts at the Andes, and on the other end the summit of small hills in which important shrines were built. These alignments extend over two hundred kilometers, thus we propose that the information codified on this shrine was based on an ancient geodetic science. A sacred geometric relationship is encrypted in the pattern formed by the position of all shrines with high accuracy, in which the Andean Chakana symbol is represented. These findings suggest that the valley of Chada could have been the sacred center of Collasuyu.

physics.hist-ph↗
arXiv2019

Is Quantum Mechanics Self-Interpreting?

Fuchs and Peres (2000) claimed that standard Quantum Mechanics needs no interpretation. In this essay, I show the flaws of the arguments presented in support to this thesis. Specifically, it will be claimed that the authors conflate QM with Quantum Bayesianism (QBism) - the most prominent subjective formulation of quantum theory; thus, they endorse a specific interpretation of the quantum formalism. Secondly, I will explain the main reasons for which QBism should not be considered a physical theory, being it concerned exclusively with agents' beliefs and silent about the physics of the quantum regime. Consequently, the solutions to the quantum puzzles provided by this approach cannot be satisfactory from a physical perspective. In the third place, I evaluate Fuchs and Peres arguments contra the non-standard interpretations of QM, showing again the fragility of their claims. Finally, it will be stressed the importance of the interpretational work in the context of quantum theory.

quant-ph↗
arXiv2019

No-Go Theorems and the Foundations of Quantum Physics

In the history of quantum physics several no-go theorems have been proved, and many of them have played a central role in the development of the theory, such as Bell's or the Kochen-Specker theorem. A recent paper by F. Laudisa has raised reasonable doubts concerning the strategy followed in proving some of these results, since they rely on the standard framework of quantum mechanics, a theory that presents several ontological problems. The aim of this paper is twofold: on the one hand, I intend to reinforce Laudisa's methodological point by critically discussing Malament's theorem in the context of the philosophical foundation of Quantum Field Theory; secondly, I rehabilitate Gisin's theorem showing that Laudisa's concerns do not apply to it.

physics.hist-ph↗
arXiv2019

The Struble-Einstein Correspondence

This article presents hitherto unpublished correspondence of Struble in 1947 with Menger, Chandrasekhar, and eventually Einstein, about a possible observational test supporting Einstein's special relativity against Ritz's emission theory using binary stars. This `Struble effect,' an acceleration Doppler effect in emission theory, appears to have been overlooked, and the historical context, including de Sitter's binary star test of special relativity, is also discussed.

gr-qc↗
arXiv2019

No master (key) No (measurement) problem

Can normal science-in the Kuhnian sense-add something substantial to the discussion about the measurement problem? Does an extended Wigner's-friend Gedankenexperiment illustrate new issues? Or a new quality of known issues? Are we led to new interpretations, new perspectives, or do we iterate the previously known? The recent debate does, as we argue, neither constitute a turning point in the discussion about the measurement problem nor fundamentally challenge the legitimacy of quantum mechanics. Instead, the measurement problem asks for a reflection on fundamental paradigms of doing physics.

quant-ph↗
arXiv2019

Archaeoastronomy in northern Chile: Andean churches of the Arica and Parinacota region

We present the results obtained from the analysis of the precise spatial orientations of almost forty old colonial Christian churches located in the Arica and Parinacota region. This is an extended and difficult to travel area that received little attention from parish priests, and where one might expect some dialogue to have taken place between the Western tradition and the local Aymara culture in regard to the design and construction of temples. We also briefly comment on our plans to explore neighboring areas to the region here studied, which include many additional historical constructions that share similar cultural traditions.

physics.hist-ph↗
arXiv2019

Kepler-9: the First Multi-Transiting System and the First Transit Timing Variations

Kepler-9, discovered by Holman et al. 2010, was the first system with multiple confirmed transiting planets and the first system to clearly show long-anticipated transit timing variations (TTVs). We review the historical circumstances behind the discovery and characterization of these planets and the publication of Holman et al. 2010. It was the first major novel exoplanet discovery of the Kepler Space Telescope mission. The Kepler pipeline identified two Saturn-radius candidates (called Kepler Objects of Interest or KOIs): KOI-377.01 with a 19-day period and KOI-377.02 with a 39-day period. Even with only 9 transits for KOI-377.01 and 6 of KOI-377.02, the transit times were completely inconsistent with a linear ephemeris and showed strongly anti-correlated variations in transit times. Holman et al. 2010 were able to readily show that these objects were planetary mass, confirming them as bona fide planets Kepler-9b and Kepler-9c. As a multi-transiting system exhibiting strong TTVs, the relative planetary properties (e.g., mass ratio, radius ratio) were strongly constrained, opening a new chapter in comparative planetology. KOI-377.03, a small planet with a 1.5-day period, was not initially discovered by the Kepler pipeline, but was identified during the analysis of the other planets and was later confirmed as Kepler-9d through the BLENDER technique by Torres et al. 2011. Holman et al. 2010 included significant dynamical analysis to characterize Kepler-9's particular TTVs: planets near resonance show large amplitude anti-correlated TTVs with a period corresponding to the rotation of the line of conjunctions and an additional "chopping" signal due to the changing positions of the planets. We also review the updated properties of this system and propose ideas for future investigations.

astro-ph.EP↗
arXiv2019

Alternative Decohering Histories in Quantum Mechanics

We continue our efforts to understand, within the framework of the quantum mechanics of the universe as a whole, the quasiclassical realm of familiar experience as a feature emergent from the Hamiltonian of the elementary particles and the initial condition of the universe. Quantum mechanics assigns probabilities to exhaustive sets of alternative decoherent histories of the universe. We introduce and define the notion of strong decoherence. We replace the notion of maximal sets of alternative decohering histories by defining the more useful concept of "full" sets of alternative strongly decohering histories. These full sets fall into equivalence classes each of which is characterized by a basis in Hilbert space. Finally we describe our continuing efforts to find measures of classicality --- measures that could be applied to such full sets of alternative strongly decohering so as to characterize a quasiclassical realm.

quant-ph↗
arXiv2019

Tokyo Wheeler or the Epistemic Preconditions of the Renaissance of Relativity

During the period identified as the Rebirth of General Relativity, John Wheeler was instrumental in retrieving the physics of gravity that had become hidden behind the mathematical formalism. For Wheeler himself the change in point of view was not from mathematics to physics; his thinking about gravity arose from, and was largely guided by, physical problems about elementary particles. We recount his development from the view of fields as derivable from particles, to fields as the more fundamental entities in nature. During the more than 10 years of his search for "particles first" Wheeler did not write an orderly sequence of accounts as his views developed, but the story could be pieced together from letters. and particularly from his extensive but seldom sequential notebook entries.

physics.hist-ph↗
arXiv2019

On the Philosophical Foundations of Physics: An Experimentalist's Perspective

Since I first became enthralled with physics as a teenager, I've been intrigued by the philosophical aspects of the discipline. As I approached the end of my career as an experimental physicist and observational astronomer (I'm now retired), I decided to return to these philosophical matters, some of which were still perturbing me, to see if I could finally make enough sense of them to quiet my discomfort. I've more or less succeeded in this quest in large part, I believe, because of my experimentalist background and a concomitant proclivity for pragmatic explanation. My purpose in this essay is to sketch a pragmatic worldview with which one might be able to approach fundamental philosophical and interpretational problems. You might ask how I can possibly expect to say anything meaningful in the less than 50 pages of the present essay? On the other hand, it might be an advantage to avoid the depth and precision that would limit flexibility in dealing with the philosophical conundrums I seek to resolve. In any case, I here offer my thoughts on the philosophical foundations of physics.

physics.hist-ph↗
arXiv2019

Einstein's biggest mistake?

What, if any, was Einstein's biggest mistake, the one most affecting our physics today? There is a perhaps apocryphal story, recounted by George Gamow, that he counted his cosmological constant as his biggest blunder. We now know his hypothesized cosmological constant to be correct. His lifelong rejection of quantum mechanics, an interesting side-story in the evolution of 20th-century physics, is a candidate. None of these introduced difficulties in how our physics is done today. It can be argued that his biggest actual mistake, one that affects many subfields of physics and chemistry and bewilders students today, occurred in his naming of his A and B coefficients.

physics.hist-ph↗
arXiv2019

The comprehensive theory of light

Modern attempts to understand light go back to Newton who considered light to be particles, the so called corpuscular theory, and the other school of Huygens, Young and others. Huygens and Young viewpoint emphasised the wave property. This difference of opinions persisted for close to two centuries till Maxwell theory solidly established light as a wave phenomenon associated with Electromagnetism. A serious schism so to speak was introduced into the theory of light with the understanding of "Light gas", the so called Black Body radiation. Einstein's photon hypothesis and Bose's successful derivation of the Planck spectrum put the corpuscular theory back in place, while classical description continues to be used as well. One may then wonder if this being a classical limit may have to be corrected when dealing with quantum phenomena. To most people's surprise, the classical description was in fact a subset of the full quantum description, and the classical states of light could be shown to be subsumed within the fully quantum description without having to take the limit of Planck's constant h going to zero. This was the resolution provided by E. C. G. Sudarshan's Diagonal representation as the most general formalism for dealing with light.

physics.hist-ph↗
arXiv2019

Bose's derivation, the crucial link to quantum mechanics

In this brief note I address the question not frequently asked, namely, why did it take two decades between Einstein's first proposal of photons and derivation of the full Planck formula from first principles of Statistical Mechanics, albeit with a fundamental new approach to counting of states. Secondly, why did it fall to an independent inquirer, S. N. Bose, in far away Dacca to arrive at the correct derivation of this formula, arguably a most crucial one of the first half of the twentieth century? Reasonable hypotheses are proposed for answers to both. I also argue that the timing of Bose's communication to Einstein played a crucial role in Einstein's approval of de Broglie's thesis and hence the emergence of the definitive version of quantum mechanics in the late 1920's.

physics.hist-ph↗
arXiv2019

Vortices and atoms in the Maxwellian era

The mathematical study of vortices began with Herman von Helmholtz's pioneering study in 1858. It was pursued vigorously over the next two decades, largely by British physicists and mathematicians, in two contexts: Maxwell's vortex analogy for the electromagnetic field and William Thomson's (Lord Kelvin) theory that atoms were vortex rings in an all-pervading ether. By the time of Maxwell's death in 1879, the basic laws of vortices in a perfect fluid in three-dimensional Euclidean space had been established, as had their importance to physics. Early vortex studies were embedded in a web of issues spanning the fields we now know as "mathematics" and "physics" - fields which had not yet become institutionally distinct disciplines but overlapped. This paper investigates the conceptual issues with ideas of force, matter, and space, that underlay mechanics and led to vortex models being an attractive proposition for British physicists, and how these issues played out in the mathematics of vortices, paying particular attention to problems around continuity. It concludes that while they made valuable contributions to hydrodynamics and the nascent field of topology, the British ultimately failed in their more physical objectives.

math.HO↗
arXiv2019

On a recently proposed dating of the foundation of Julia Augusta Taurinorum (Torino)

Recently, a preprint [arXiv:1901.08545] and a series of news announced that Torino, as the roman Augusta Taurinorum, was founded on 30 January 9 BC. The assumption is based on the coincidence of the Julian date, obtained by means of astronomical calculations, and the date of the inauguration, by Augustus, of the Ara Pacis in Rome (historical date). Here we show that, in the framework proposed in [1], the abovementioned date of the foundation is impossible. The impossibility is based on the following fact. The Julian date (30 January 9 BC), proposed by the authors in [arXiv:1901.08545], cannot definitely be the historical 30 January 9 BC of the Julian Calendar.

physics.hist-ph↗
arXiv2019

Killing Science Fiction: Why Conscious States Cannot Be Copied or Repeated

Several philosophical problems arising from the physics of consciousness, including identity, duplication, teleportation, simulation, self-location, and the Boltzmann Brain problem, hinge on one of the most deeply held but unnecessary convictions of physicalism: the assumption that brain states and their corresponding conscious states can in principle be copied. In this paper I will argue against this assumption by attempting to prove the Unique History Theorem, which states, essentially, that conscious correlations to underlying quantum mechanical measurement events must increase with time and that every conscious state uniquely determines its history from an earlier conscious state. By assuming only that consciousness arises from an underlying physical state, I will argue that the physical evolution from a first physical state giving rise to a conscious state to a second physical state giving rise to a later conscious state is unique. Among the consequences of this theorem are that: consciousness is not algorithmic and a conscious state cannot be uploaded to or simulated by a digital computer; a conscious state cannot be copied by duplicating a brain or any other physical state; and a conscious state cannot be repeated or created de novo. These conclusions shed light on the physical nature of consciousness by rendering moot a variety of seemingly paradoxical philosophy and science fiction problems.

physics.hist-ph↗
arXiv2019

Naturalness as a reasonable scientific principle in fundamental physics

I aim to clarify the physical content and significance of naturalness. Physicists' earliest understanding of naturalness, as an autonomy of scales (AoS) requirement provides the most cogent definition of naturalness and I will assert that i) this provides a uniform notion which undergirds a myriad prominent naturalness conditions, ii) this is a reasonable criterion to impose on EFTs and iii) the successes and violations of naturalness are best understood when adhering to this notion of naturalness. I argue that this principle is neither an aesthetic nor a sociologically-influenced principle. I contend that naturalness may only be plausibly argued to be an aesthetic/sociological principle when formal measures of naturalness and their use in physics communities are conflated with the central dogma of naturalness - the former may indeed be argued to be sociologically-influenced and somewhat arbitrary - but these formal measures of naturalness are in fact less successful than AoS naturalness. I put forward arguments as to why AoS naturalness is well-defined and why it was reasonable for physicists to endorse this naturalness principle on both theoretical and empirical grounds. Up to date, no compelling reasons have appeared as to why the laws of nature should generically decoupling into quasi-autonomous physical domains. A decoupling of scales in the quantum realm is often claimed to be entailed by the Decoupling Theorem (Cao and Schweber (1993)), yet I will show that this theorem is too weak to underwrite quasi-autonomous physical domains in quantum field theories because one should additionally impose that parameters be natural. Violations of naturalness would then have ontological import - unnatural parameters would not be accurately described by EFTs but rather by field theories exhibiting some kind of UV/IR interplay.

physics.hist-ph↗