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arXiv2015

The Hydrogen Atom: a Review on the Birth of Modern Quantum Mechanics

The purpose of this work is to retrace the steps that were made by scientists of XX century, like Bohr, Schrodinger, Heisenberg, Pauli, Dirac, for the formulation of what today represents the modern quantum mechanics and that, within two decades, put in question the classical physics. In this context, the study of the electronic structure of hydrogen atom has been the main starting point for the formulation of the theory and, till now, remains the only real case for which the quantum equation of motion can be solved exactly. The results obtained by each theory will be discussed critically, highlighting limits and potentials that allowed the further development of the quantum theory.

physics.hist-ph↗
arXiv2015

Optimizing the Ptolemaic Model of Planetary and Solar Motion

Ptolemy-s planetary model is an ancient geocentric astronomical model, describing the observed motion of the Sun and the planets. Ptolemy accounted for the deviations of planetary orbits from perfect circles by introducing two small and equal shifts into his model. We show that Ptolemy-s choice of shifts allowed him to approximate the true eccentricity of planetary orbits only in the first order, linear in eccentricity. We show that, if the shifts were tuned in the ratio 5/3, the model precision could be improved substantially, perhaps delaying its rejection. The best achievable precision is quadratic in eccentricities. Although, to achieve it fully, one would have to introduce Ptolemaic shifts in the epicycles as well as in deferents the planets.

physics.hist-ph↗
arXiv2015

A structural theory of everything

In this paper it is argued that Barad's Agential Realism, an approach to quantum mechanics originating in the philosophy of Niels Bohr, can be the basis of a 'theory of everything' consistent with a proposal of Wheeler that observer-participancy is the foundation of everything. On the one hand, agential realism can be grounded in models of self-organisation such as the hypercycles of Eigen, while on the other agential realism, by virtue of the 'discursive practices' that constitute one aspect of the theory, implies the possibility of the generation of physical phenomena through acts of specification originating at a more fundamental level. Included in phenomena that may be generated by such a mechanism are the origin and evolution of life, and human capacities such as mathematical and musical intuition.

physics.gen-ph↗
arXiv2015

Haag's Theorem as a Reason to Reconsider Direct-Action Theories

It is argued that the severe consequences of Haag's inconsistency theorem for relativistic quantum field theories can be successfully evaded in the direct-action approach. Some recent favorable comments of John Wheeler, often mistakenly presumed to have abandoned his own (and Feynman's) direct-action theory, together with the remarkable immunity of direct-action quantum electrodynamics to Haag's theorem, suggest that it may well be a good time to rehabilitate direct action theories. It is also noted that, as extra dividends, direct-action QED is immune to the self-energy problem of standard gauge field QED, and can also provide a solution to the problem of gauge arbitrariness.

quant-ph↗
arXiv2015

Symmetries, Symmetry Breaking, Gauge Symmetries

The concepts of symmetry, symmetry breaking and gauge symmetries are discussed, their operational meaning being displayed by the observables {\em and} the (physical) states. For infinitely extended systems the states fall into physically disjoint {\em phases} characterized by their behavior at infinity or boundary conditions, encoded in the ground state, which provide the cause of symmetry breaking without contradicting Curie Principle. Global gauge symmetries, not seen by the observables, are nevertheless displayed by detectable properties of the states (superselected quantum numbers and parastatistics). Local gauge symmetries are not seen also by the physical states; they appear only in non-positive representations of field algebras. Their role at the Lagrangian level is merely to ensure the validity on the physical states of local Gauss laws, obeyed by the currents which generate the corresponding global gauge symmetries; they are responsible for most distinctive physical properties of gauge quantum field theories. The topological invariants of a local gauge group define superselected quantum numbers, which account for the $θ$ vacua.

physics.hist-ph↗
arXiv2015

No-localidad, multiuniverso y principio cosmologico en un modelo simple de espacio-tiempo

Here we analyze the physical concepts of non-locality, multi-universe, and cosmological principle in the framework of a space-time discrete model previously developed. In previous developments of this model we have elucidated as derivative concepts those of time, space-time, reference frame, particle, interaction between systems of particles, field, interaction between fields, detector of particle, and wave function. We start from the primitive concept of preparticle and four postulates alluding simple concepts. The fundamental postulate says that space-time points can be represented by equivalent classes of points of crossing between particles having the same structure. In this way each point of space-time is represented by an equivalent class corresponding to a different structure from the one of any other equivalent class representing a space-time point. We have considered a new way to define system of observation and detector of particles, which leads to non- local properties of the space-time model considered. Finally we have speculated about dark matter and dark energy in the frame work of our model.

physics.gen-ph↗
arXiv2015

General and Stronger Uncertainty Relation

Recently, Maccone and Pati [Phys. Rev. Lett. {\bf 113}, 260401 (2014)] derived few inequalities among variances of incompatible operators which they called stronger uncertainty relations, stronger than Heisenberg-Robertson or Schrodinger uncertainty relations. Here we generalize their study to get infinite number of such inequalities and propose that only one of them may be the correct uncertainty relation between incompatible operators. We get back well known uncertainty relations of Heisenberg-Robertson and Schrodinger under certain limits. We also reexamine the conclusions of Maccone and Pati and comment on their work.

quant-ph↗
arXiv2015

The de Broglie Wave as Evidence of a Deeper Wave Structure

It is argued that the de Broglie wave is not the wave usually supposed, but the relativistically induced modulation of an underlying carrier wave that moves with the velocity of the particle. In the rest frame of the particle this underlying structure has the form of a standing wave. De Broglie also assumed the existence of this antecedent standing wave, but it would appear that he failed to notice its survival as a carrier wave in the Lorentz transformed wave structure. Identified as a modulation, the de Broglie wave acquires a physically reasonable ontology, evidencing a more natural unity between matter and radiation than might otherwise be contemplated, and avoiding the necessity of recovering the particle velocity from a superposition of such waves. Because the Schrödinger and other wave equations for massive particles were conceived as equations for the de Broglie wave, this interpretation of the wave is also relevant to such issues in quantum mechanics as the meaning of the wave function, the nature of wave-particle duality, and the possibility of well-defined particle trajectories.

physics.hist-ph↗
arXiv2017

Some Generalities About Generality

We survey a variety of cosmological problems where the issue of generality has arisen. This is aimed at providing a wider context for many claims and deductions made when philosophers of science choose cosmological problems for investigation. We show how simple counting arguments can be used to characterise parts of the general solution of Einstein's equations when various matter fields are present and with different spatial topologies. Applications are described to the problem of singularities, static cosmological models, cosmic no hair theorems, the late-time isotropisation of cosmological models, and the number of parameters needed to describe a general astronomical universe.

gr-qc↗
arXiv2015

Causarum Investigatio and the Two Bell's Theorems of John Bell

"Bell's theorem" can refer to two different theorems that John Bell proved, the first in 1964 and the second in 1976. His 1964 theorem is the incompatibility of quantum phenomena with the joint assumptions of Locality and Predetermination. His 1976 theorem is their incompatibility with the single property of Local Causality. This is contrary to Bell's own later assertions, that his 1964 theorem began with the assumption of Local Causality, even if not by that name. Although the two Bell's theorems are logically equivalent, their assumptions are not. Hence, the earlier and later theorems suggest quite different conclusions, embraced by operationalists and realists, respectively. The key issue is whether Locality or Local Causality is the appropriate notion emanating from Relativistic Causality, and this rests on one's basic notion of causation. For operationalists the appropriate notion is what is here called the Principle of Agent-Causation, while for realists it is Reichenbach's Principle of common cause. By breaking down the latter into even more basic Postulates, it is possible to obtain a version of Bell's theorem in which each camp could reject one assumption, happy that the remaining assumptions reflect its weltanschauung. Formulating Bell's theorem in terms of causation is fruitful not just for attempting to reconcile the two camps, but also for better describing the ontology of different quantum interpretations and for more deeply understanding the implications of Bell's marvellous work.

quant-ph↗
arXiv2016

Generalized Quantum Theory, Contextual Emergence and Non-Hierarchic Alternatives

The concept of emergence is critically analyzed in particular with respect to the assumed emergence of mental properties from a neuronal basis. We argue that so-called contextual emergence is needed to avoid an eliminatory reductionism. Quantum-like features of the emergent qualities are to be expected. As a consequence, non-causal relations like entanglement correlations have to be considered as full fledged elements of reality. "Observable extension" is proposed as a contextual alternative to emergence avoiding the asymmetry between purportedly basic and emergent properties.

physics.hist-ph↗
arXiv2015

Revisiting the Majorana Relativistic Theory of Particles with Arbitrary Spin

In 1932 Ettore Majorana published an article proving that relativity allows any value for the spin of a quantum particle and that there is no privilege for the half integer spin. The Majorana idea was so innovative for the time that the scientific community understood its importance only towards the end of the thirties. This paper aims to highlight the depth of the scientific thought of Majorana that, well in advance of its time, opened the way for modern particle physics and introduced for the first time the idea of a universal quantum equation, able to explain the behavior of particles with arbitrary spin and of any nature, regardless the value of their speed. It will be analyzed in detail and made explicit all the steps that lead to the physical mathematical formulation of the Majorana theory. A part of these steps require basic knowledge of quantum physics but not for this should be regarded as trivial since they show the physical meaning hidden into the structure of the equation. Moreover, the explicit method for the construction of the infinite matrices will be given, by which the infinite components of the wave functions representing the fundamental and excited states of the particle are calculated.

physics.hist-ph↗
arXiv2015

The contribution of Giordano Bruno to the principle of relativity

The trial and condemnation of Giordano Bruno was mainly based on arguments of philosophical and theological nature, and therefore different from Galilei's. Such elements contribute to unfairly devalue the scientific contribution of Bruno and do not properly account in particular for his contribution to physics. This paper discusses the contribution of Bruno to the principle of relativity. According to common knowledge, the special principle of relativity was first enunciated in 1632 by Galileo Galilei in his Dialogo sopra i due massimi sistemi del mondo (Dialogue concerning the two chief world systems), using the metaphor today known as "Galileo's ship": in a boat moving at constant speed, the mechanical phenomena can be described by the same laws holding on Earth. We shall show that the same metaphor and some of the examples in Galilei's book were already contained in the dialogue La cena de le Ceneri (The Ash Wednesday Supper) published by Giordano Bruno in 1584. In fact, Giordano Bruno largely anticipated the arguments of Galilei on the relativity principle. It is likely that Galilei was aware of Bruno's work, and it is possible that the young Galilei discussed with Bruno, since they both stayed in Venezia for long periods in 1592.

physics.hist-ph↗
arXiv2015

The Consistent Histories Formalism and the Measurement Problem

In response to a recent rebuttal of [1] presented in [2], we defend the claim that the Consistent Histories formulation of quantum mechanics does not solve the measurement problem. In order to do so, we argue that satisfactory solutions to the problem must not only not contain anthropomorphic terms (such as measurement or observer) at the fundamental level, but also that applications of the formalism to concrete situations (e.g., measurements) should not require any input not contained in the description of the situation at hand at the fundamental level. Our assertion is that the Consistent Histories formalism does not meet the second criterion. We also argue that the so-called second measurement problem, i.e., the inability to explain how an experimental result is related to a property possessed by the measured system before the measurement took place, is only a pseudo-problem. As a result, we reject the claim, defended in [2], that the capacity of the Consistent Histories formalism to solve it should count as an advantage over other interpretations.

quant-ph↗
arXiv2015

Operationalization of Basic Observables in Mechanics

This novel approach to the foundation of the physical theory begins with Hermann von Helmholtz fundamental analysis of basic measurements. We explain the mathematical formalism from the operationalization of basic observables. According to Leibniz resp. Galilei we define energy, momentum and mass from the elemental comparison "more capability to work than" (against same test system) and "more impact than" (in a collision) and develop Helmholtz program for direct quantification. From vivid pre-theoretic (principle of inertia, impossibility of perpetuum mobile, relativity principle) and measurement methodical principles we derive the fundamental equations of mechanics.

physics.hist-ph↗
arXiv2015

The water clock of the Bronze Age (Northern Black Sea Coast)

In the article presents the results of the multidisciplinary study conducted with the help of archaeological, physical and astronomical methods. The aim of the study was to analyze and interpret marks and drawings applied to the surface of the vessel of the Bronze Age (Srubna culture) found near the Staropetrovsky village (Donetsk region, Ukraine) near the border between the Donetsk and Lugansk regions. The carried out calculations and measurements possible to prove that staropetrovsky vessel is the most ancient water clock, discovered on the territory of Europe, and have approximately the same age as the oldest known ancient Egyptian water clock. Such vessels - water clocks were needed for Srubna population to mark sundial, which had recently been discovered in the Northern Black Sea Coast. Based on the analysis of marks on the outside of the vessel, it was revealed that Staropetrovsky vessel is unique ancient complex device for measuring time and at the same time using a water clock, and with the help of a sundial, allows to monitor of the uneven apparent motion of the Sun long before the existing written evidence about such monitoring. Series of marks on the outer surface of the vessel and on its corolla was associated with the star Sirius and its heliacal rising. Given in this paper the results of astronomical calculations allow to state that astronomical beginning of the year recorded since the heliacal rising of Sirius at the Srubna population of the Northern Black Sea Coast. Keywords: archaeoastronomy, modeling, Srubna culture, vessel, marks, water clock, sundial, equation of time, Sirius, heliacal rising.

physics.hist-ph↗
arXiv2015

The Descent of Math

A perplexing problem in understanding physical reality is why the universe seems comprehensible, and correspondingly why there should exist physical systems capable of comprehending it. In this essay I explore the possibility that rather than being an odd coincidence arising due to our strange position as passive (and even more strangely, conscious) observers in the cosmos, these two problems might be related and could be explainable in terms of fundamental physics. The perspective presented suggests a potential unified framework where, when taken together, comprehenders and comprehensibility are part of causal structure of physical reality, which is considered as a causal graph (network) connecting states that are physically possible. I argue that in some local regions, the most probable states are those that include physical systems which contain information encodings - such as mathematics, language and art - because these are the most highly connected to other possible states in this causal graph. Such physical systems include life and - of particular interest for the discussion of the place of math in physical reality - comprehenders capable of making mathematical sense of the world. Within this framework, the descent of math is an undirected outcome of the evolution of the universe, which will tend toward states that are increasingly connected to other possible states of the universe, a process greatly facilitated if some physical systems know the rules of the game. I therefore conclude that our ability to use mathematics to describe, and more importantly manipulate, the natural world may not be an anomaly or trick, but instead could provide clues to the underlying causal structure of physical reality.

physics.hist-ph↗