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Amelia Carolina Sparavigna

Publications and source records attributed to Amelia Carolina Sparavigna.

At least 19 recordsLinked to original sources

Orientation of Entrance and Burial Chamber in the Pyramids of the Egyptian Fourth and Fifth Dynasties

In a recent work, arxiv:2412.20407, we have mentioned two Egyptian kings, Shepseskaf and Userkaf, of the IV and V Dynasties. Here we continue discussing their burial places, that is their pyramids, in a new framework based on the study of orientation of pyramid substructures (entrances, corridors, burial chambers). Shepseskaf and Userkaf opted for the same architectonic solutions, exhibiting a continuity in funerary architecture. After showing the substructure orientations of the pyramids of the IV and V Dynasties, we will stress that the substructure in the Shepseskaf's pyramid, the Mastabat Fara'un, is oriented as in the Fourth Dynasty architecture of pyramids and that it has a layout which is closer to that used by the following Fifth Dynasty. In our discussion, we will start with the first ruler of the Fourth Dynasty, Snefru, who introduced a new form of external and internal layout of the burial complexes of the king, through an evolution based on four attempts, the Seila, Meidum, Bent and Red pyramids. In the final model, the Snefru's Red pyramid, the substructure has a north entrance and a burial chamber east-west oriented. This orientation persisted in the pyramids of the Fourth and Fifth Dynasties, and beyond. The Sekhemkhet (Djoserty) pyramid of the Third Dynasty is also illustrated for comparison, such as some earlier burial monuments. In the discussion here proposed the position of sarcophagus and of the body inside it is also investigated. The sarcophagus has its axis north-south. The body of the deceased king was lying on its left side, extended, head to the north, face towards the east. In this framework, we propose again what we told in arXiv 2016, arxiv:1604.05963, and the layout of pyramids with respect to sunrise on solstices.

physics.hist-ph↗

Two Egyptian Kings, Shepseskaf and Userkaf, and a solar eclipse (2471 BC)

Recently, arXiv published a work by G. Magli about the eclipse of 1 April 2471 BC and a supposed influence of it on the end of the fourth Egyptian dynasty and the beginning of the fifth one. In Magli's arXiv/2412.13640 paper, the eclipse is defined as the 'Shepseskaf eclipse'. Magli considers that this eclipse happened during the reign of the 'last ruler of the 4th dynasty, Shepseskaf'. Some literature is giving the name of further members of this dynasty. Therefore, here we add some references, besides those given in arXiv. We will show that, in this literature, the same eclipse of 2471 BC is linked to king Userkaf of the fifth dynasty. Some observations about chronological data proposed by Magli are also necessary. Since in arxiv/2412.13640 paper we find mentioned by Magli the pyramid of Cheops (that is Akhet Khufu, a name which is generally translated as the Khufu's horizon) and the symbol of the 'solarized' horizon, N27 of the Gardiner's list, it is necessary to stress that the word Akhet was written with the crested ibis, G25, as clearly shown by the Wadi al-Jarf papyri, which are contemporary to Khufu's reign. Mark Lehner, 2001, recognizing a translation problem, rendered Akhet Khufu as the 'Spirit of Khufu'. The use of the crested ibis, in a locution translated as 'dwellers of the horizon' is attested in a Pepi II letter to his vizier Herkhuf, then three centuries after Khufu.

physics.hist-ph↗

Timekeeping at Akhet Khufu, as shown by the Diary of Merer

The discovery of the Diary of Merer (papyri Wadi al-Jarf) allows us to see the Egyptian calendar applied in a logbook. The diary is dated to the 26th year of reign of Khufu and describes Merer and his crew transporting the limestone blocks from the Tura quarries to Akhet Khufu, that is, the pyramid of Khufu (Old Kingdom). We find a calendar with 30-day months, 10-day weeks, five epagomenal days (Tallet, 2017) and Merer's job adapted to the seasons of the year. Seasons and epagomenal days have names according to inscriptions on the east wall of the Tehne tomb of Nj-k'-'nh (Nikaiankh), end of Fourth Dynasty or early Fifth Dynasty. The Diary gives us an overall impression of extreme modernity in the logistics of ancient Egypt. And Merer looks like a person with a reputation for good timekeeping at Akhet Khufu.

physics.pop-ph↗

q-Gaussian Tsallis line shapes and Raman spectral bands

q-Gaussians are probability distributions having their origin in the framework of Tsallis statistics. A continuous real parameter q is characterizing them so that, in the range 1 < q < 3, the q-functions pass from the usual Gaussian form, for q close to 1, to that of a heavy tailed distribution, at q close to 3. The value q=2 corresponds to the Cauchy-Lorentzian distribution. This behavior of q-Gaussian functions could be interesting for a specific application, that regarding the analysis of Raman spectra, where Lorentzian and Gaussian profiles are the line shapes most used to fit the spectral bands. Therefore, we will propose q-Gaussians with the aim of comparing the resulting fit analysis with data available in literature. As it will be clear from the discussion, this is a very sensitive issue. We will also provide a detailed discussion about Voigt and pseudo-Voigt functions and their role in the line shape modeling of Raman bands. We will show a successfully comparison of these functions with q-Gaussians. The role of q-Gaussians in EPR spectroscopy (Howarth et al., 2003), where the q-Gaussian is given as the ''Tsallis lineshape function'', will be reported. Two examples of fitting Raman D and G bands with q-Gaussians are proposed too.

physics.gen-ph↗

Decomposition of waves in time series of data related to Covid-19

Here it is proposed a decomposition in components of the''waves'' which appear in the time series of data related to Covid-19 pandemic. The decomposition is based on functions of \k{appa}-statistics; in particular the \k{appa}-Weibull is used. Fitted data are those of the ''waves'' ranging from August 2020 to April 2021 in the United Kingdom, from September 2020 to May 2021 in Ireland, and from September 2020 to June 2021 in Italy. For the United Kingdom, the time series of daily infection shows a wave composed by two peaks. Among the many factors involved in the spread of infection, it seems that, in driving the onset of the second peak, the main role was played by the emergence of Alpha variant of Sars-Cov-2. Therefore, the proposed decomposition of waves in the time series is applied to study the role of Alpha variant in the spread of infection. For what concerns data from Ireland, if we decompose the analysed ''wave'' in three components, we can observed that for one of them the role of the Alpha variant was relevant for sure. In the case of Italy, the effect is less evident, because it was spread over a larger time interval.

physics.soc-ph↗

Bononia, the Roman Bologna: Archaeoastronomy and Chronology

In an article written by Giulio Magli on the orientation of the Roman towns, Bononia, the Roman Bologna, is given as a specific example to support Magli's thesis on the existence of preferred solar alignments of the urban layout. Assuming that the Roman towns had been oriented to the sunrise on a given day of the year, Magli suggested possible preferred alignments according to Roman festivals, in particular the festival of Terminalia. Of Bononia, we know the date of foundation as Roman colony in 189 BC, given by Livy. We will show that, according to Roman chronology and Republican calendar, it is impossible that Bononia had been oriented to the sunrise on the day given by Livy. The discrepancy is huge. Moreover, the direction of the decumanus cannot match the dates of Terminalia for 189 BC. However, if we consider that the layout that we see today is that of a recolonization under Octavian, we can have a certain agreement between the direction of the decumanus and the sunrise on the day of Terminalia (within three days), and a perfect agreement with the day of the festival of Armilustrium. In the proposed discussion, we will stress in particular the problem of the discrepancy between the historical dates of Roman chronology and the Julian dates, those that we can find according to an astronomical analysis. This problem is general and must be properly considered in any archaeoastronomical analysis of Roman towns.

physics.hist-ph↗

Julia Augusta Taurinorum, an archaeoastronomical reload

Discussion of an astronomical orientation of Turin as Julia Augusta Taurinorum, based on the results previously given in 2012 and available at arXiv:1206.6062, and here refined according to the local natural horizon, the refraction of atmosphere, and the use of software Stellarium. Besides the evaluation of a possible astronomical orientation, the use of the azimuth of Via Garibaldi, which is corresponding to the Roman decumanus, shows that the town is following the geometrical rules of Roman varatio.

physics.pop-ph↗

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↗

The Roman Colonia Marciana Ulpia Traiana Thamugadi (Timgad) and Trajan's Birthday

It is told that the Roman Colonia Marciana Ulpia Traiana Thamugadi, that is Timgad in Algeria, had been oriented to the sunrise on the day of Trajan's birthday, that is 18 September 100 AD. Here we use software CalSKY to investigate the sunrise azimuth and compare it to the direction of the decumanus of the Roman town.

physics.pop-ph↗

Supernova 1572 and other newly observed stars in the literature of the time

SN 1572, also known as the Tycho's Nova, was a supernova largely reported and discussed in the literature of the time. Here we talk about this literature. In the latest texts, we find also mentioned the Kepler's Nova, today known as SN 1604, and other newly observed stars. We discuss them too.

physics.hist-ph↗

Magnetic Compasses and Chinese Architectures

In this paper, we are discussing the effect of the use of magnetic compasses on the orientation of ancient Chinese architectonical complexes. As Czech researchers proposed in 2011, assuming these complexes ideally oriented by the ancient architects along north-south direction, in the case that the surveys were made by means of magnetic compasses, we can find the axes of the complexes deviating from the cardinal direction, according to the local magnetic declination that existed at the time the structures were built. Following this idea, here we discuss some examples of possible alignments obtained by means of magnetic compasses, concluding that the Chinese surveyors adopted, during the Ming dynasty, a method based on the magnetic compasses. The architects of the antecedent Yuan Dynasty probably used an astronomical method.

physics.hist-ph↗

A method for the segmentation of images based on thresholding and applied to vesicular textures

In image processing, a segmentation is a process of partitioning an image into multiple sets of pixels, that are defined as super-pixels. Each super-pixel is characterized by a label or parameter. Here, we are proposing a method for determining the super-pixels based on the thresholding of the image. This approach is quite useful for studying the images showing vesicular textures.

cs.CV↗

A possible role of Alpha Crucis in the astronomical landscape of Silbury Hill

The paper is proposing a possible link between the construction of the Silbury Hill, the prehistoric artificial mound near Avebury, and the observation of Alpha Crucis, the main star of the Crux constellation, which was slowly disappearing from the local sky due to the precession of the Earth's axis. For the discussion, we used simulations of the local astronomical landscape made by means of Stellarium software.

physics.hist-ph↗

Evaluating Urbanization from Satellite and Aerial Images by means of a statistical approach to the texture analysis

Statistical methods are usually applied in the processing of digital images for the analysis of the textures displayed by them. Aiming to evaluate the urbanization of a given location from satellite or aerial images, here we consider a simple processing to distinguish in them the 'urban' from the 'rural' texture. The method is based on the mean values and the standard deviations of the colour tones of image pixels. The processing of the input images allows to obtain some maps from which a quantitative evaluation of the textures can be obtained.

cs.CV↗

Vito Volterra and his commemoration for the centenary of Faraday's discovery of electromagnetic induction

The paper presents a memoir of 1931 written by Vito Volterra on the Italian physicists of the nineteenth century and the researches these scientists made after the discoveries of Michael Faraday on electromagnetism. Here, the memoir entitled "I fisici italiani e le ricerche di Faraday" is translated from Italian. It was written to commemorate the centenary of Faraday's discovery of the electromagnetic induction. Besides being a remarkable article on the history of science, it was also, in a certain extent, a political paper. In fact, in 1931, the same year of the publication of this article, Mussolini imposed a mandatory oath of loyalty to Italian academies. Volterra was one of the very few professors who refused to take this oath of loyalty. Because of the political situation in Italy, Volterra wanted to end his paper sending a message to the scientists of the world, telling that the feeling of admiration and gratitude that in Italy the scientists had towards "the great thinker and British experimentalist" was profound and unanimous.

physics.hist-ph↗

Overlapping Circles Grid Drawn with Compass and Straightedge on an Egyptian Artifact of 14th Century BC

The study of the mathematics and geometry of ancient civilizations is a task which seems to be very difficult or even impossible to fulfil, if few written documents, or none at all, had survived from the past. However, besides the direct information that we can have from written documents, we can gain some indirect evidence on mathematics and geometry also from the analysis of the decorations we find on artifacts. Here, for instance, we will show that ancient Egyptians were able of making geometric constructions using compass and straightedge, quite before the Greek Oenopides of Chois, who lived around 450 BC, had declared some of their basic principles. In fact, a wood panel covered by an overlapping circles grid pattern, found in the tomb of Kha, an architect who served three kings of 18th Dynasty (1400-1350 BC), evidences that some simple constructions with compass and straightedge were used in ancient Egypt about nine centuries before Oenopides' time.

math.HO↗

Khufu, Khafre and Menkaure Pyramids and the Sun

In this paper we discuss the orientation of the Egyptian pyramids at Giza with respect to sunrises and sunsets, using SunCalc.net software. We can see that Khufu and Khafre pyramids had been positioned in a manner that, from each pyramid, it was always possible to observe the points of the horizon where the sun was rising and setting on each day of the year. A discussion for the Menkaure pyramid is also proposed.

physics.hist-ph↗

Depletion Gilding: An Ancient Method for Surface Enrichment of Gold Alloys

Ancient objects made of noble metal alloys, that is, gold with copper and/or silver, can show the phenomenon of surface enrichment. This phenomenon is regarding the composition of the surface, which has a percentage of gold higher than that of the bulk. This enrichment is obtained by a depletion of the other elements of the alloy, which are, in some manner, removed. This depletion gilding process was used by pre-Columbian populations for their 'tumbaga', a gold-copper alloy, to give it the luster of gold.

physics.pop-ph↗