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arXiv2009

A contribution to the history of quarks: Boris Struminsky's 1965 JINR publication

The idea that an internal quantum number for quarks, eventually called color, can explain the magnetic moments of baryons within the framework of standard quantum theory, was explicitly stated in a 7th January, 1965 JINR publication by Boris Struminsky (JINR P-1939). A complete translation into English of Struminsky's letter is presented along with page images of the original booklet found in the JINR Library.

physics.hist-ph↗

arXiv2010

At the other end of the sun's path. A new interpretation of Machu Picchu

The Inca citadel of Machu Picchu is usually interpreted as a "royal estate" of the Inca ruler Pachacuti. This idea is challenged here by a critical reappraisal of existing sources and a re-analysis of existing evidences. It is shown that such evidences actually point at a quite different interpretation. This interpretation is suggested, on one side, by several clues coming from the urban layout, the interior arrangement of the town, the ancient access ways, the position with respect to the landscape and the cycles of the celestial bodies in Inca times and, on the other side, by a comparison with known information about the Inca pilgrimage center on the Island of the Sun of the Titicaca lake. Altogether, the abovementioned clues lead to propose that Machu Picchu was intentionally planned and built as a pilgrimage center connected with the Inca "cosmovision".

physics.hist-ph↗

arXiv2009

Copenhagen Interpretation of Quantum Theory and the Measurement Problem

The Copenhagen interpretation of quantum theory is investigated from a philosophical point of view. It is justified the opinion that the philosophical attitude the Copenhagen interpretation is based on is in principle inevitable for a real comprehension of quantum theory. This attitude is mainly related to epistemological arguments. However, the measurement problem often seems not to be treated clearly enough within the interpretation. By referring to the property of the necessity to use macroscopic measurement instruments obeying classical concepts it is made the attempt to solve the measurement problem. According to this consideration the indeterministic character of quantum theory seems to have its origin in a lack of knowledge and thus it appears in a similar but more principle way than in statistical mechanics. It is emphasized the ontological character of the uncertainty relation and the related non locality of quantum theory suggesting that the existence of a position space is not as fundamental as the assumptions of general quantum theory.

physics.hist-ph↗

arXiv2010

Regarding Llewellyn Thomas's paper of 1927 and the "hidden momentum" of a magnetic dipole in an electric field

L. H. Thomas, in his 1927 paper, "The Kinematics of an Electron with an Axis", explained the then-anomalous factor of one-half in atomic spin-orbit coupling as due to a relativistic precession of the electron spin axis. Thomas's explanation required also that the total of the orbit-averaged, or "secular", orbital and spin angular momenta of the electron be a conserved quantity, as he found to be the case for either of two possible equations of translational motion of the magnetic electron. Thomas's finding is seen in the present work to require the "hidden momentum" of the electron intrinsic magnetic moment in the Coulomb field of the proton be omitted from its equation of translational motion. Omission of the hidden momentum is contrary to the position of standard modern electrodynamics texts, and leads to violation of Newton's law of action and reaction, negating Thomas's result. Including the hidden momentum results in linear momentum conservation, but in the presence of Thomas precession, the total angular momentum is not generally conserved. The total angular momentum precesses for non-aligned spin and orbit, even in the absence of externally-applied magnetic field. As Thomas observes that secular angular momentum conservation is a necessary condition for a consistent simultaneous description of spin-orbit coupling and the anomalous Zeeman effect, such is not possible within classical electrodynamics in its absence.

physics.gen-ph↗

arXiv2009

Orientations of the Giant's Churches in Ostrobothnia, Finland

The orientations of 23 Giant's Churches, dating from 2500-2000 BCE, located in Ostrobothnia, Finland, have been measured. Many of them are found to have orientations to the risings and settings of the sun on the main solar dates of the year.

physics.hist-ph↗

arXiv2009

Adler sum rule

The Adler sum rule states that the integral over energy of a difference of neutrino-nucleon and antineutrino-nucleon structure functions is a constant, independent of the four-momentum transfer squared. This constancy is a consequence of the local commutation relations of the time components of the hadronic weak current, which follow from the underlying quark structure of the standard model.

hep-ph↗

arXiv2009

The fourth Dimension

In different passages of his dialogues, Plato showed deep mathematically-based physical insights. Regrettably most readers overlooked the respective statements, or they utterly did not understand those hints since they were full of philological fallacious terms. Respectable translators misinterpreted such statements and therefore Plato's respective remarks were not recognized as substantial knowledge. Furthermore, Plato often supplemented such basic remarks by diffusely veiled and varied allusions that were often ironically hidden somewhere in his dialogues by inconspicuous double meanings. However, this mode of intentionally coded discrete communication was generally not understood because such irony is not to everyone's taste. However, the attempts to reconstruct Plato's system on the basis of admittedly individually interpreted double meanings lead to a conclusive mathematical-physical cyclical system of dimensions. Additionally it was possible to assign Plato's system of philosophical ideas analogously to this cyclical system. Plato took the verifiability of the mathematical-physical results as proof of the system of his ideas and finally as proof of his ethical creed, the unconditional trust in the 'all surmounting Good.'

physics.gen-ph↗

arXiv2009

The Order of Sir Bondi

The direct and indirect relationship between the British physicist originally from Austria, Sir Hermann Bondi, and Venezuelan physics are presented. Special emphasis is made of his more remarkable human qualities, nobility and humbleness, besides his important contribution to General Relativity and to the European science agencies. Self--declared as a staunch disciple of Popperian philosophy, Bondi defended the "hard and dirty" physics against the "inmaculate and beauty" physics. Attention is focused on two cornerstones of Bondi's work, followed thoroughly by Luis Herrera and disciples in Venezuela.

physics.hist-ph↗

arXiv2009

The question "Are We Alone?" in different cultures

A survey of the worldwide litterature reveals that the question "Are We Alone in the Universe?" has been formulated only in the western litterature. Here I try to understand why it is so. To investigate this problem it is first necessary to clarify what western culture means.

physics.hist-ph↗

arXiv2009

Effective Field Theory, Past and Future

This is a written version of the opening talk at the 6th International Workshop on Chiral Dynamics, at the University of Bern, Switzerland, July 6, 2009, to be published in the proceedings of the Workshop. In it, I reminisce about the early development of effective field theories of the strong interactions, comment briefly on some other applications of effective field theories, and then take up the idea that the Standard Model and General Relativity are the leading terms in an effective field theory. Finally, I cite recent calculations that suggest that the effective field theory of gravitation and matter is asymptotically safe.

hep-th↗

arXiv2009

The mystery of the telescopes in Jan Brueghel the Elder's paintings

Several early spyglasses are depicted in five paintings by Jan Brueghel the Elder completed between 1608 and 1625, as he was court painter of Archduke Albert VII of Habsburg. An optical tube that appears in the Extensive Landscape with View of the Castle of Mariemont, dated 1608-1612, represents the first painting of a telescope whatsoever. We collected some documents showing that Albert VII obtained spyglasses very early directly from Lipperhey or Sacharias Janssen. Thus the painting likely reproduces one of the first man-made telescopes ever. Two other instruments appear in two Allegories of Sight made in the years 1617 and 1618. These are sophisticated instruments and the structure suggests that they may be keplerian, but this is about two decades ahead this mounting was in use.

astro-ph.IM↗

arXiv2010

Nuclear Reactions

Nuclear reactions generate energy in nuclear reactors, in stars, and are responsible for the existence of all elements heavier than hydrogen in the universe. Nuclear reactions denote reactions between nuclei, and between nuclei and other fundamental particles, such as electrons and photons. A short description of the conservation laws and the definition of basic physical quantities is presented, followed by a more detailed account of specific cases: (a) formation and decay of compound nuclei; (b)direct reactions; (c) photon and electron scattering; (d) heavy ion collisions; (e) formation of a quark-gluon plasma; (f) thermonuclear reactions; (g) and reactions with radioactive beams. Whenever necessary, basic equations are introduced to help understand general properties of these reactions. Published in Wiley Encyclopedia of Physics, ISBN-13: 978-3-527-40691-3 - Wiley-VCH, Berlin, 2009.

nucl-th↗

arXiv2009

Theory and Applications of Coulomb Excitation

Because the interaction is well-known, Coulomb excitation is one of the best tools for the investigation of nuclear properties. In the last 3 decades new reaction theories for Coulomb excitation have been developed such as: (a) relativistic Coulomb excitation, (b) Coulomb excitation at intermediate energies, and (c) multistep coupling in the continuum. These developments are timely with the advent of rare isotope facilities. Of special interest is the Coulomb excitation and dissociation of weakly-bound systems. I review the Coulomb excitation theory, from low to relativistic collision energies. Several applications of the theory to situations of interest in nuclear physics and nuclear astrophysics are discussed.

nucl-th↗

arXiv2009

Orientation of the northern gate of the Goseck Neolithic rondel

The two southernmost gates of the Goseck rondel, built by the Stichbandkeramik culture around 4800 BCE, were oriented to the winter solstice sunrise and sunset. The northern gate of the rondel deviates a few degrees from the Meridian line. It is suggested that this deviation from the cardinal direction is due a stellar orientation towards Edasich, which was the pole star at the time, and is thus related to the concept of the world pillar and the pole star as the top of it.

physics.hist-ph↗

arXiv2009

Matter from Space

General Relativity offers the possibility to model attributes of matter, like mass, momentum, angular momentum, spin, chirality etc. from pure space, endowed only with a single field that represents its Riemannian geometry. I review this picture of `Geometrodynamics' and comment on various developments after Einstein.

physics.hist-ph↗

arXiv2009

Naming the extrasolar planets

Extrasolar planets are not named and are referred to only by their assigned scientific designation. The reason given by the IAU to not name the planets is that it is considered impractical as planets are expected to be common. I advance some reasons as to why this logic is flawed, and suggest names for the 403 extrasolar planet candidates known as of Oct 2009. The names follow a scheme of association with the constellation that the host star pertains to, and therefore are mostly drawn from Roman-Greek mythology. Other mythologies may also be used given that a suitable association is established.

astro-ph.EP↗

arXiv2010

ETTORE MAJORANA: Introduzione a vita & opere (ETTORE MAJORANA: An introduction to his life and work)

This agile small "book" (in Italian) is an introduction to the life and work of Ettore Majorana, the brightest Italian theoretical physicist of the XX century, regarded by Enrico Fermi as the best theoretician of his time in the world. It consists of ten smooth chapters, only few of them being moderately technical, and of three Appendices: (i) about his inaugural lecture on physics at the University of Naples; (ii) about some notes of his, on the role of the statistical laws in physics and in the social sciences; and (iii) with a recapitulatory biographic outline. The present material is mainly taken from our previous book "Il Caso Majorana: Epistolario, Documenti, Testimonianze", first published (1987, 1991) by Mondadori, Milan, and recently (2000, 2002, 2008) published by Di Renzo Editore, Rome. That book presented practically all the serious documents existing on Majorana's life & work [indeed, almost all the biographical documents have been discovered or collected, during a few decades, by the present author, who was the first to publish them]. Actually, we might address to such a book (c/o www.direnzo.it, "Arcobaleno" series) all the readers interested in more and deeper information.

physics.pop-ph↗

arXiv2009

Phenomenological Quantum Gravity

If the history of science has taught us anything, it's that persistence and creativity makes the once impossible possible. It has long been thought experimental tests of quantum gravity are impossible. But during the last decade, several different approaches have been proposed that allow us to test, if not the fundamental theory of quantum gravity itself, so at least characteristic features this theory can have. For the first time we can probe experimentally domains in which quantum physics and gravity cohabit, in spite of our failure so far to make a convincing marriage of them on a theoretical level.

physics.pop-ph↗