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arXiv2016

Phil Anderson's Magnetic Ideas in Science

In Philip W. Anderson's research, magnetism has always played a special role, providing a prism through which other more complex forms of collective behavior and broken symmetry could be examined. I discuss his work on magnetism from the 1950s, where his early work on antiferromagnetism led to the pseudospin treatment of superconductivity - to the 70s and 80s, highlighting his contribution to the physics of local magnetic moments. Phil's interest in the mechanism of moment formation, and screening evolved into the modern theory of the Kondo effect and heavy fermions.

cond-mat.str-el↗

arXiv2016

Event ontology in quantum mechanics and downward causation

We show that several interpretations of quantum mechanics admit an ontology of objects and events. This ontology reduces the breach between mind and matter. When humans act, their actions do not appear explainable in mechanical terms but through mental activity: motives, desires or needs that propel them to action. These are examples of what in the last few decades have come to be called "downward causation". Basically, downward causation is present when the disposition of the whole to behave in a certain way cannot be predicted from the dispositions of the parts. The event ontology of quantum mechanics allow us to show that systems in entangled states present emergent new properties and downward causation.

quant-ph↗

arXiv2016

Bell's Universe: A Personal Recollection

My collaboration and friendship with John Bell is recollected. I will explain his outstanding contributions in particle physics, in accelerator physics, and his joint work with Mary Bell. Mary's work in accelerator physics is also summarized. I recall our quantum debates, mention some personal reminiscences, and give my personal view on Bell's fundamental work on quantum theory, in particular, on the concept of contextuality and nonlocality of quantum physics. Finally, I describe the huge influence Bell had on my own work, in particular on entanglement and Bell inequalities in particle physics and their experimental verification, and on mathematical physics, where some geometric aspects of the quantum states are illustrated.

physics.hist-ph↗

arXiv2016

"Dancing with the stars" - astronomy and music in the Torres Strait

Song and dance are a traditional means of strengthening culture and passing knowledge to successive generations in the Torres Strait of northeastern Australia. Dances incorporate a range of apparatuses to enhance the performance, such as dance machines (Zamiyakal) and headdresses (Dhari). The dances, songs, headdresses and dance machines work together to transfer important knowledge about subsistence survival, social structure, and cultural continuity. This paper explores how celestial phenomena inspire and inform music and dance.

physics.hist-ph↗

arXiv2016

The Development of Elementary Quantum Theory from 1900 to 1927

Planck's introduction of the quantum of action in 1900 was followed by 25 years of trial and error in quest of the understanding of the quantum world; different ideas and directions had to be pursued until the path leading to the elementary quantum theory was discovered. Radical changes away from traditional perceptions about natural phenomena were necessary, the entire system of basic concepts in classical physics had to be abandoned and replaced by a new mode of thought. Continuity and determinism of classical laws were no longer applicable on the quantum scale, where dynamical behaviour proceeds by discontinuous and statistical quantum transitions. Albert Einstein laid the essential foundations for the new concept; Max Born made the decisive step further leading to the breakthrough in 1925. The development of the ideas, which eventually resulted in the elementary quantum theory in 1925/26, will be described, relying on original publications and letters written during that period in time by the major contributors. The fundamental laws of Quantum Theory derived by Max Born and Pascual Jordan may mathematically be represented in many different ways, and particular emphasis is given to the distinction between physical content and mathematical representation.

physics.hist-ph↗

arXiv2016

Nancy Cartwright and the Logic of Quantum Mechanics

This paper deals with Nancy Cartwright's views on the measurement problem in Quantum Mechanics, as exposed in her book {\it{How the Laws of Physics Lie}}. She does not accept the logic of Quantum Mechanics. It is argued that her proposals, which are at variance with many facts results and epistemics of Quantum Mechanics are the result of her choice of classical logic, which leads her to propose the transition rate as the fundamental object of Quantum Mechanics. I argue that this is incorrect. The positions which Nancy Cartwright defends on the reduction of the wave packet do not address the fundamental issue, i.e. the duality of a world where quantum and classical objects coexist and interact. I suggest that the main problem with Nancy Cartwright's positions is her difficulty in accepting that the contradiction at the basis of Quantum Mechanics, i.e. the simultaneous corpuscular and wave-like nature of quantum objects, is a fact of nature. Recent experiments, described in this paper, shed a new light on the foundations of Quantum Mechanics and on the topic of this paper. The limits of the no-contradiction principle are discussed; modern dialectical materialism is argued to offer a useful framework for the interplay between knowledge and reality.

physics.hist-ph↗

arXiv2016

The dichotomy between 'practical' and 'theoretical' astronomy in ancient and late antique literature

In Plato's dialogues Republic and Laws, the most important disciplines for the best education of the rulers of the city are identified with arithmetic, geometry and astronomy. Those disciplines, however, are not intended for practical applications, but to reach the truth and see the form of good. In particular, another dialogue, Epinomis, stresses on the relevance of astronomy itself as main discipline, since it coincides with the study of the gods, that is, the planets and the heaven. According to Epinomis, the wise astronomer does not observe the risings and settings of stars for practical applications such as the farmer calendar, but he studies the orbits of the planets. Therefore, the 'practical' astronomy of farmers appears intrinsically less important than the 'theoretical' one, i.e. the study of the planetary motions. We discuss the possibly far-reaching negative implications of such a specific discrimination. We report some examples taken from Greek and Latin literature illustrating the difficulties of a coherent description of the risings and settings of stars that was attempted by scholars, and should have been of little help for farming. We conclude by pointing out the practical importance of astronomy (intended in a broad sense) even today, and of the dangers of the separation or discrimination of disciplines and sub-disciplines for the culture during the present global economic crisis.

physics.hist-ph↗

arXiv2016

Yokohama to Ruby Valley : Around the World in 80 Years. II

We two had year-long research leaves in Japan, working together fulltime with several Japanese plus Tony De Groot back in Livermore and Harald Posch in Vienna. We summarize a few of the high spots from that very productive year ( 1989-1990 ), followed by an additional fifteen years' work in Livermore, with extensive travel. Next came our retirement in Nevada in 2005, which has turned out to be a long-term working vacation. Carol narrates this part of our history together.

physics.hist-ph↗

arXiv2017

Unscrambling the Omelette of Quantum Contextuality (PART 1): Preexistent Properties or Measurement Outcomes?

In this paper we attempt to analyze the physical and philosophical meaning of quantum contextuality. We will argue that there exists a general confusion within the foundational literature arising from the improper "scrambling" of two different meanings of quantum contextuality. While the first one, introduced by Bohr, is related to an epistemic interpretation of contextuality which stresses the incompatibility (or complementarity) of certain measurement situations described in classical terms; the second meaning of contextuality is related to a purely formal understanding of contextuality as exposed by the Kochen-Specker (KS) theorem which focuses instead on the constraints of the orthodox quantum formalism in order to interpret projection operators as preexistent or actual (definite valued) properties. We will show how these two notions have been scrambled together creating an "omelette of contextuality" which has been fully widespread through a popularized "epistemic explanation" of the KS theorem according to which: The measurement outcome of the observable A when measured together with B or together with C will necessarily differ in case [A, B] = [A, C] = 0, and [B, C] /= 0. We will show why this statement is not only improperly scrambling epistemic and formal perspectives, but is also physically and philosophically meaningless. Finally, we analyze the consequences of such widespread epistemic reading of KS theorem as related to statistical statements of measurement outcomes.

quant-ph↗

arXiv2016

Archaeoastronomy and the chronology of the Temple of Jupiter at Baalbek

One of the most complex architectural feats ever conceived is the magnificent temple of Jupiter at Baalbek, Lebanon. Several issues remain unsolved about this site, and in particular the chronology and dating of the two podia and the true nature of the cult. We present here some hints coming from orientation and from other features of the temple, which seem to point to a unified project of both podia, originally conceived under Herod the Great.

physics.hist-ph↗

arXiv2016

The Story of the Neutrino

This is an elementary review of the history and physics of neutrinos. The story of the discovery of neutrino mass through neutrino oscillations is described in some detail. Experiments on solar neutrinos and atmospheric neutrinos played an important part. Recent advances are summarized and future developments are indicated.

physics.pop-ph↗

arXiv2016

Life, Intelligence and Multiverse

Hypothetical existence of other universes gives an opportunity not only to extend the scope of physics, but the scope of biology, SETI, and METI as well. Some steps of the development of alien life concept shall be briefly summarized, then the multiverse proposal shall be used as a framework of interpretation to introduce an extended taxonomy of possible or at least imaginable types of life and intelligence based on either different biochemistry or physics. Some consequences shall be presented about SETI and METI in connection with both multiverse hypothesis and anthropic principle.

physics.hist-ph↗

arXiv2016

The Transactional Interpretation and its Evolution into the 21st Century: An Overview

This essay provides a historical, philosophical, and critical overview of the development of the Transactional Interpretation of Quantum Mechanics (TI). It is separated into two parts. Part I presents the history and development of TI from 1986 up to 2016 (the time of writing). Part II lays out current areas of divergence among researchers in TI.

quant-ph↗

arXiv2018

On the nature of discrete space-time: The atomic theory of space-time and its effects on Pythagoras's theorem, time versus duration, inertial anomalies of astronomical bodies, and special relativity at the Planck scale

In this work, resolutions will be given for commonly stated problems associated with a model that assumes that space and time are discretized (i.e., atomized). This model is in contrast to the continuous space-time model that is used in all common physical theories and equations -- a model that assumes that spatial coordinates and time are continuous variables. The resolutions to the problems are arrived at, not by proposing any new theories or postulates, but by strictly adhering to: Ernst Mach's principle of non-absolute space, the tenets of logical positivism, quantum mechanics and general relativity. The problems associated with discrete space-time addressed in this paper include: Lorentz contraction (time dilation) of the ostensibly smallest spatial (temporal) interval, maintaining isotropy, violations of causality, and conservation of energy and momentum. Importantly, this work yields modifications to the standard formulae for time dilation and length contraction, with these modifications preserving the quantums of space and time and allowing for temporary travel at the speed of light. Also given are: a resolution to Weyl's tile argument, a modification of the 2500 year old Pythagoras's theorem, a reassessment of Henri Bergson's theory advocating a distinction between the time durations measured by scientists and an immutable "Time", and a discussion of whether Einstein's light-clocks are as ideal as most scientist believe. Also included is a demonstration of how discrete space imposes order upon John Wheeler's quantum foam such that the foam becomes a gravity crystal permeating all space and producing measurable inertial anomalies of astronomical bodies.

physics.class-ph↗

arXiv2016

How the green light was given for gravitational wave search

The recent detection of gravitational waves by the LIGO/VIRGO team is an incredibly impressive achievement of experimental physics. It is also a tremendous success of the theory of General Relativity. It confirms the existence of black holes; shows that binary black holes exist; that they may collide and that during the merging process gravitational waves are produced. These are all predictions of General Relativity theory in its fully nonlinear regime. The existence of gravitational waves was predicted by Albert Einstein in 1916 within the framework of linearized Einstein theory. Contrary to common belief, even the very \emph{definition} of a gravitational wave in the fully nonlinear Einstein theory was provided only after Einstein's death. Actually, Einstein had arguments against the existence of nonlinear gravitational waves (they were erroneous but he did not accept this), which virtually stopped development of the subject until the mid 1950s. This is what we refer to as the \emph{Red Light} for gravitational waves research. In the following years, the theme was picked up again and studied vigorously by various experts, mainly Herman Bondi, Felix Pirani, Ivor Robinson and Andrzej Trautman, where the theoretical obstacles concerning gravitational wave existence were successfully overcome, thus giving the `Green Light' for experimentalists to start designing detectors, culminating in the recent LIGO/VIRGO discovery. In this note we tell the story of this theoretical breakthrough. Particular attention is given to the fundamental 1958 papers of Trautman, which seem to be lesser known outside the circle of General Relativity experts. A more detailed technical description of these 2 papers is given in the Appendix.

physics.hist-ph↗

arXiv2017

Can we Falsify the Consciousness-Causes-Collapse Hypothesis in Quantum Mechanics?

In this paper we examine some proposals to disprove the hypothesis that the interaction between mind and matter causes the collapse of the wave function, showing that such proposals are fundamentally flawed. We then describe a general experimental setup retaining the key features of the ones examined, and show that even a more general case is inadequate to disprove the mind-matter collapse hypothesis. Finally, we use our setup provided to argue that, under some reasonable assumptions about consciousness, such hypothesis is unfalsifiable.

quant-ph↗

arXiv2016

The theoretical physics ecosystem behind the discovery of the Higgs boson

The discovery of the Higgs boson in 2012 was one of the most significant developments of science in the last half century. A simplified history has Peter Higgs positing it in the mid-1960s followed by a long wait while experimentalists progressively turned up collider energies until it appeared several decades later. However, in order for both the hypothesis and the experimental discovery to occur, a vast and complex theory ecosystem had to thrive in the years before Higgs's hypothesis and in the years that followed, building up to its discovery. It is further claimed that the Higgs boson hypothesis was an immoderate speculation, and therefore faith in theory argumentation and speculation was mandatory for the discovery program to proceed and reach its fulfillment. The Higgs boson could not have been discovered experimentally by accident.

physics.hist-ph↗

arXiv2016

Reconstructing the Star Knowledge of Aboriginal Tasmanians

The canopy of stars is a central presence in the daily and spiritual lives of Aboriginal Tasmanians. With the arrival of European colonists, Tasmanian astronomical knowledge and traditions were interrupted and dispersed. Fragments can be found scattered in the ethnographic and historical record throughout the nineteenth century. We draw from ethnohistorical documents to analyse and reconstruct Aboriginal astronomical knowledge in Tasmania. This analysis demonstrates that stars, the Milky Way, constellations, dark nebula, the Sun, Moon, meteors, and aurorae held cultural, spiritual, and subsistence significance within the Aboriginal cultures of Tasmania. We move beyond a monolithic view of Aboriginal astronomical knowledge in Tasmania, commonly portrayed in previous research, to lay the groundwork for future ethnographic and archaeological fieldwork with Aboriginal elders and communities.

physics.hist-ph↗