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Giulio Magli

Publications and source records attributed to Giulio Magli.

At least 37 records · Page 2Linked to original sources

Sirius and the project of the megalithic enclosures at Gobekli Tepe

The megalithic enclosures of Gobekli Tepe (Urfa, Turkey) are the most ancient sacred structures of stone known so far, dating back to the 10 millennium BC. The possible presence of astronomical targets for these structures is analysed, and it turns out that they may have been oriented, or even originally constructed, to celebrate and successively follow the appearance of a new, extremely brilliant star in the southern skies: Sirius.

physics.hist-ph↗

The astronomical orientation of the urban plan of Alexandria

Alexander the Great founded Alexandria in 331 BC. The newly founded town was conceived as an orthogonal grid based on a main longitudinal axis, later called Canopic Road. We analyse here the astronomical orientation of the project and propose that the main axis was deliberately oriented towards the rising sun on the day of birth of Alexander the Great. The argument is admittedly speculative as any Archaeoastronomy argument not backed up by written sources. However, it is nested accurately into the archaeological records and into what is known on the foundation of the town. Further, a topographical analysis is given to sustain the thesis.

physics.hist-ph↗

Reconstruction of ancient conceptual landscapes in the Nile Valley

Conceptual landscapes in Egypt show a remarkable continuity - for as long as 2000 years - in the use of symbols and in the interplay between natural and man-built features. Directionality, both in the sense of succession of elements and of orientation of single buildings and tombs, plays a key role in governing the landscape in accordance with the idea of "cosmic" order, which was the basis of the temporal power of the pharaoh. Comparing satellite image with local surveys and using simple web-based instruments for tracing visibility lines helps in understanding connections and messages which were meant to be clear and obvious in ancient times but may be lost, or forgotten, today. In particular, the prominent role of astronomical and topographical alignments in the planning of successive monuments comes out at sites like Abydos, Giza, Dahshur and at Western Thebes. The way in which the same symbols and elements were elaborated by the "heretic" pharaoh Akhenaten in planning the landscape of his capital at Amarna is also highlighted.

physics.hist-ph↗

A cognitive approach to the topography of the 12th dynasty pyramids

The topography of the royal pyramids of the 12th dynasty is investigated in its historical and chronological context, in order to highlight connections between the architectural choices, the religious ideas and the traditions inspiring the reign of the corresponding pharaohs. A close, explicit connection with the double building projects carried out more than six centuries before by Snefru at Dahshur and at Meidum-Seila comes out. This connection involved geometry, perspective and astronomical alignments in the progressive planning of the pyramidal complexes. In such a context, the architectural choices of the last great king of the dynasty, Amenemhet III - who built two pyramids, one at Dahshur and the other at Hawara - appear to be due mostly to symbolic, as opposed to practical, reasons.

physics.hist-ph↗

Geometry and perspective in the landscape of the Saqqara pyramids

A series of peculiar, visual alignments between the pyramids of the pharaohs of the 4, 5 and 6 Egyptian dynasties exists. These alignments governed from the very beginning the planning of the funerary monuments of successive kings and, in some cases, led to establish building sites in quite inconvenient locations from the technical viewpoint. Explaining the topography of these monuments means therefore also investigating on their symbolic motivations: religion, power, dynastic lineage and social context, as well as getting insights on the skills of the ancient architects in astronomy and geometry. In the present paper we focus on the relationships between the Old Kingdom pyramids at Saqqara.

physics.hist-ph↗

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↗

The role of the sun in the Pantheon's design and meaning

Despite being one of the most recognisable buildings from ancient Rome, the Pantheon is poorly understood. While its architecture has been well studied, its function remains uncertain. This paper argues that both the design and the meaning of the Pantheon are in fact dependent upon an understanding of the role of the sun in the building, and of the apotheosised emperor in Roman thought. Supporting evidence is drawn not only from the instruments of time in the form of the roofed spherical sundial, but also from other Imperial monuments, notably Nero's Domus Aurea and Augustus's complex of structures on the Campus Martius: his Ara Pacis, the "Horologium Augusti", and his Mausoleum. Hadrian's Mausoleum and potentially part of his Villa at Tivoli are drawn into this argument as correlatives. Ultimately, it is proposed that sun and time were linked architecturally into cosmological signposts for those Romans who could read such things.

physics.hist-ph↗

Topography, astronomy and dynastic history in the alignments of the pyramid fields of the Old Kingdom

It is known since the 19 century that in the layout of the pyramid field of the pharaohs of the 4 th Egyptian dynasty at Giza, a main axis exists. Indeed, the south-east corners of these monuments align towards the site of the temple of Heliopolis, which was plainly visible in ancient times. It was later discovered that a similar situation occurs in the main pyramid field of the subsequent dynasty at Abu Sir. Here, the northwest corners of three chronologically successive pyramids again voluntarily align towards Heliopolis. However, the temple was in this case not visible, due to the rock outcrop today occupied by the Cairo citadel which blocks the view. In the present paper, a interdisciplinary approach based on historical, topographical and archaeoastronomical analysis is developed in an attempt at understanding such peculiar features, which governed from the very beginning the planning of these wonderful monuments. A general pattern actually arises, which appears to have inspired the choice of the sites and the disposition on the ground of almost all the funerary complexes of the kings during the Old Kingdom. In particular, this pattern helps to explain the choices in the location of the funerary complexes of Niuserre in Abusir and of Unas in Saqqara.

physics.hist-ph↗

Aligned electromagnetic excitations of a black hole and their impact on its quantum horizon

We show that elementary aligned electromagnetic excitations of black holes, as coming from exact Kerr-Schild solutions, represent light-like beam pulses which have a very strong back reaction on the metric and change the topology of the horizon. Based on York's proposal, that elementary deformations of the BH horizon are related with elementary vacuum fluctuations, we analyze deformation of the horizon caused by the beam-like vacuum fluctuations and obtain a very specific feature of the topological deformations of the horizon. In particular, we show how the beams pierce the horizon, forming a multitude of micro holes in it. A conjecture is taken into consideration, that these specific excitations are connected with the conformal-analytic properties of the Kerr geometry and are at the base of the emission mechanism.

hep-th↗

The dynamical behaviour of homogeneous scalar-field spacetimes with general self-interaction potentials

The dynamics of homogeneous Robertson--Walker cosmological models with a self-interacting scalar field source is examined here in full generality, requiring only the scalar field potential to be bounded from below and divergent when the field diverges. In this way we are able to give a unified treatment of all the already studied cases - such as positive potentials which exhibit asymptotically polynomial or exponential behaviors - together with its extension to a much wider set of physically sensible potentials. Since the set includes potentials with negative inferior bound, we are able to give, in particular, the analysis of the asymptotically anti De Sitter states for such cosmologies.

gr-qc↗

Possible astronomical references in the planning of the Great Hopewell Road

The possible existence of astronomical references in the planning of the so-called Great Hopewell Road, a 90 Kilometres straight road composed of two parallel earthen embankments which, according to recent surveys, likely connected the Hopewell ceremonial centres of Newark and Chillicothe, Ohio, are investigated. It turns out that a very peculiar, although simple, set of astronomical alignments took place in connection with the road during possible periods of its construction. The possibility of a non-fortuitous connection is thus proposed and analysed.

physics.hist-ph↗

A calendar Quipu of the early 17th century and its relationship with the Inca astronomy

The so-called Miccinelli documents are a set of documents which were written by Jesuit scholars in Peru within the first half of the 17th century. Among such documents, one contains the depiction of a Quipu, that is, a device made out of cords of different nature and colors which, with the help of nodes, were used by the Incas for storing data. This Quipu is claimed by the author, Blas Valera, to be a reproduction of the Inca calendar of the year of the Spanish conquest. We give here a complete analysis of the astronomical events occurred in Cusco in that year, showing that they actually correspond closely to the data reported in the Quipu, and compare the calendrical information - such as the names and the rituals of each month - with those given by other documents, especially the Nuova Coronica by G. Poma de Ayala. The possible relevance of the document for the knowledge of the original Inca lore of the sky is discussed in details.

physics.hist-ph↗

Akhet Khufu: archaeo-astronomical hints at a common project of the two main pyramids of Giza, Egypt

The architectural complexes composed by the two main pyramids of Giza together with their temples are investigated from an inter-disciplinary point of view, taking into account their astronomical alignments as well as their relationships with the visible landscape. Combining already known facts together with new clues, the work strongly supports the idea that the two complexes were conceived as parts of a common project.

physics.hist-ph↗

On the orientation of Roman towns in Italy

As is well known, several Roman sources report on the existence of a town foundation ritual, inherited from the Etruscans, which allegedly included astronomical references. However, the possible existence of astronomical orientations in the layout of Roman towns has never been tackled in a systematic way. As a first step in this direction, the orientation of virtually all Roman towns in Italy (38 cities) is studied here. Non-random orientation patterns emerge from these data, aiming at further research in this field.

physics.pop-ph↗

Rotating "Black Holes" with Holes in the Horizon

Kerr-Schild solutions of the Einstein-Maxwell field equations, containing semi-infinite axial singular lines, are investigated. It is shown that axial singularities break up the black hole, forming holes in the horizon. As a result, a tube-like region appears which allows matter to escape from the interior without crossing the horizon. It is argued that axial singularities of this kind, leading to very narrow beams, can be created in black holes by external electromagnetic or gravitational excitations and may be at the origin of astrophysically observable effects such as jet formation.

gr-qc↗