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Even if laboratory practice is essential for all scientific branches of knowledge, it is often neglected at High School, due to lack of time and/or resources. To establish a closer contact between school and experimental sciences, the University Sapienza of Roma and the Istituto Nazionale di Fisica Nucleare (INFN) launched the Lab2Go project, with the goal of spreading laboratory practice among students and teachers in high schools., Comment: in Italian

The theme of the influence of Bourbaki's ideas and methodologies on disciplines that transcend the mathematical field has been frequently addressed and, in particular, the reflection on the relationship between Bourbaki and Oulipo has animated a passionate debate within literary criticism. The purpose of this contribution is to investigate the relations between Le Lionnais, Queneau and Roubaud - and more generally Oulipo - and Bourbaki. Through a comparative examination between the two groups, the existence of an undeniable charisma of the "polycephalic mathematician" on the artistic-literary movement was highlighted., Comment: in Italian

The aim of this thesis is to present the notion of spaces whose curvature is bounded above, and to give some of its application in the context of Combinatorial Algebra. The thesis is made of two parts, one of theoretic purpose, and the other applicative. In particular, we present an application to the notion of $CAT(0)$-space and one to the Gromov Theorem for cubical complexes. In the final part we present a new class of discrete groups generalizing the well-known right-angled Artin groups. We concoct a cubical CAT(0)-complex on which the group acts, from whom we extract some algebraic properties of such groups., Comment: 53 pages, in Italian

The question of whether Cosmic Microwave Background (CMB) temperature and polarization data from Planck favor a spatially closed Universe with curvature parameter $\Omega_K<0$ has been the subject of recent intense discussions. Attempts to break the geometrical degeneracy combining Planck data with external datasets such as Baryon Acoustic Oscillation (BAO) measurements all point towards a spatially flat Universe, at the cost of significant tensions with Planck, which make the resulting dataset combination problematic. Settling this issue requires identifying a dataset which can break the geometrical degeneracy while not incurring in these tensions. We argue that cosmic chronometers (CC), measurements of the expansion rate $H(z)$ from the relative ages of massive early-type passively evolving galaxies, are the dataset we are after. Furthermore, CC come with the additional advantage of being virtually free of cosmological model assumptions. Combining Planck 2018 CMB temperature and polarization data with the latest CC measurements, we break the geometrical degeneracy and find $\Omega_K=-0.0054 \pm 0.0055$, consistent with a spatially flat Universe and competitive with the Planck+BAO constraint. Our results are stable against minimal parameter space extensions and CC systematics, and we find no substantial tension between Planck and CC data within a non-flat Universe, making the resulting combination reliable. Our results allow us to assert with confidence that the Universe is spatially flat to the ${\cal O}(10^{-2})$ level, a finding which might possibly settle the ongoing spatial curvature debate, and lends even more support to the already very successful inflationary paradigm., Comment: 30 pages, 6 figures. The busy reader should skip to Fig. 1 and Tab. 3 for the main results, and to Fig. 5 and Tab. 4 if they are interested in the extended parameter space results. "Piatto" = "flat" in Italian, "Note added" between conclusions and acknowledgements explains our choice of title. v2: abstract shortened, references added, version accepted for publication in ApJ. Comments are welcome

I think that the main reason why we do not understand the general principles of how knowledge works (and probably also the reason why we have not yet designed and built efficient machines capable of artificial intelligence), is not the excessive complexity of cognitive phenomena, but the lack of the conceptual and methodological tools to properly address the problem. It is like trying to build up Physics without the concept of number, or to understand the origin of species without including the mechanism of natural selection. In this paper I propose some new conceptual and methodological tools, which seem to offer a real opportunity to understand the logic of cognitive processes. I propose a new method to properly treat the concepts of structure and schema, and to perform on them operations of structural analysis. These operations allow to move straightforwardly from concrete to more abstract representations. With these tools I will suggest a definition for the concept of rule, of regularity and of emergent phenomena. From the analysis of some important aspects of the rules, I suggest to distinguish them in operational and associative rules. I propose that associative rules assume a dominant role in cognition. I also propose a definition for the concept of problem. At the end I will briefly illustrate a possible general model for cognitive systems., Comment: In Italian

In memory of the famous physicist Bruno Pontecorvo, whereof is just occurred the centenary anniversary of the birth and the twentieth anniversary of the death, this paper traces the scientific and human adventure of the italian scientist, from the pioneering studies of nuclear physics together with his master Enrico Fermi, to the excellent results in particle physics, in particular his research and insights about the neutrino. As much attention is paid to the human experience, his relationship with politics and the choice to embrace the Soviet socialist model. A short portrait to commemorate a scientist symbol of the twentieth century., Comment: in Italian

English. The following document pursues the objective of comparing some useful methods to balance a dataset and obtain a trained model. The dataset used for training is made up of short and medium length sentences, such as simple phrases or extracts from conversations that took place on web channels. The training of the models will take place with the help of the structures made available by the Apache Spark framework, the models may subsequently be useful for a possible implementation of a solution capable of classifying sentences using the distributed environment, as described in "New frontier of textual classification: Big data and distributed calculation" by Massimiliano Morrelli et al. Italiano. Il seguente documento persegue l'obiettivo di mettere a confronto alcuni metodi utili a bilanciare un dataset e ottenere un modello addestrato. Il dataset utilizzato per l'addestramento \`e composto da frasi di lunghezza breve e media, come frasi semplici o estratte da conversazioni avvenute su canali web. L'addestramento dei modelli avverr\`a con l'ausilio delle strutture messe a disposizione dal framework Apache Spark, i modelli successivamente potranno essere utili a un eventuale implementazione di una soluzione in grado di classificare frasi sfruttando l'ambiente distribuito, come descritto in "Nuova frontiera della classificazione testuale: Big data e calcolo distribuito" di Massimiliano Morrelli et al., Comment: in Italian

Application of Benford's law to data on daily new cases of infection by Covid 2019 in some Coutries (Brazil, China, France, Germany, Japan, Italy, United Kingdom, United States of America)., Comment: Text in Italian

This article, written in Italian language, explores the contribution given by Bayes' rule and by subjective probability in the work at Bletchley Park towards cracking Enigma cyphered messages during WWII. -- In questo articolo, scritto in Italiano, esploriamo il contributo dato dal teorema di Bayes e dalle idee della probabilit\`a soggettiva nel lavoro compiuto a Bletchley Park che ha portato a decifrare i messaggi cifrati con macchine Enigma durante la Seconda Guerra Mondiale., Comment: 39 pages, 10 figures, in Italian

The impact of Machine Learning (ML) algorithms in the age of big data and platform capitalism has not spared scientific research in academia. In this work, we will analyse the use of ML in fundamental physics and its relationship to other cases that directly affect society. We will deal with different aspects of the issue, from a bibliometric analysis of the publications, to a detailed discussion of the literature, to an overview on the productive and working context inside and outside academia. The analysis will be conducted on the basis of three key elements: the non-neutrality of science, understood as its intrinsic relationship with history and society; the non-neutrality of the algorithms, in the sense of the presence of elements that depend on the choices of the programmer, which cannot be eliminated whatever the technological progress is; the problematic nature of a paradigm shift in favour of a data-driven science (and society). The deconstruction of the presumed universality of scientific thought from the inside becomes in this perspective a necessary first step also for any social and political discussion. This is the subject of this work in the case study of ML., Comment: Originally published in Italian on the journal The Lab's Quarterly

This report presents an analysis of #hashtags used by Italian Cultural Heritage institutions to promote and communicate cultural content during the COVID-19 lock-down period in Italy. Several activities to support and engage users' have been proposed using social media. Most of these activities present one or more #hashtags which help to aggregate content and create a community on specific topics. Results show that on one side Italian institutions have been very proactive in adapting to the pandemic scenario and on the other side users' reacted very positively increasing their participation in the proposed activities., Comment: in Italian

Starting from Sinclair's 1976 work {\it Automatic Continuity of Linear Operators}, Cambridge University Press, (1976), on automatic continuity of linear operators on Banach spaces, we prove that sequences of intertwining continuous linear maps are eventually constant with respect to the separating space of a fixed linear map. Our proof uses a gliding hump argument. We also consider aspects of continuity of linear functions between locally convex spaces and prove that such that a linear function $T$ from the locally convex space $X$ to the locally convex space $Y$ is continuous whenever the separating space $G(T)$ is the zero vector in $Y$ and for which $X$ and $Y$ satisfy conditions for a closed graph theorem., Comment: Several minor errors corrected. Accepted for publication, November, 2019, in Italian Journal of Pure and Applied Mathematics, to appear in 2021

English. This document aims to study the best algorithms to verify the belonging of a specific document to a related domain by comparing different methods for calculating the distance between two vectors. This study has been made possible with the help of the structures made available by the Apache Spark framework. Starting from the study illustrated in the publication "New frontier of textual classification: Big data and distributed calculus" by Massimiliano Morrelli et al., We wanted to carry out a study on the possible implementation of a solution capable of calculating the Similarity of a sentence using the distributed environment. Italiano. Il presente documento persegue l'obiettivo di studiare gli algoritmi migliori per verificare l'appartenenza di un determinato documento a un relativo dominio tramite un confronto di diversi metodi per il calcolo della distanza fra due vettori. Tale studio \`e stato condotto con l'ausilio delle strutture messe a disposizione dal framework Apache Spark. Partendo dallo studio illustrato nella pubblicazione "Nuova frontiera della classificazione testuale: Big data e calcolo distribuito" di Massimiliano Morrelli et al., si \`e voluto realizzare uno studio sulla possibile implementazione di una soluzione in grado di calcolare la Similarit\`a di una frase sfruttando l'ambiente distribuito., Comment: in Italian

This short paper focuses on Schr\"oder's contribute towards a structural view of group theory., Comment: in Italian

In this paper, our aim is to discuss the outcome of a ten-year experimental workshop activity carried out by the Center `matematita' (http://www.matematita.it/) with classes of pre-university students of any age. We analyse the potential benefits of this way of teaching and learning mathematics, both from the point of view of students and teachers., Comment: In Italian

We propose in detail Antennas for generating Nondiffracting Beams of Microwaves, for instance with frequencies of the order of few GHz, obtaining fair results even when having recourse to realistic apertures, with a quite reasonable diameter. The present proposal refers to sets of suitable annular slits. The possible applications are various, including remote sensing. The paper is in Italian. [Si propongono in dettaglio Antenne per la generazione di fasci non-diffrattivi di microonde, per frequenze ad esempio dell'ordine della decina di GHz, ottenendo discreti risultati pur ricorrendo ad antenne realistiche di diametro ridotto. La proposta e' quella di usare un set di opportuni Annular Slits. Le applicazioni possibili sono varie, includendo il remore sensing.], Comment: 16 pages with 8 figures. Source-file in LaTeX (in Italian, with English abstract)

English: If the current status of theoretical and experimental knowledge in Nuclear Physics could be reduced to a geographical chart or a planisphere, then our epoch would be in some respect comparable to the end of the Medieval age and in other to the beginning of the Reinassance: epochs in which, together with the consolidated knowledge of the Old World, there have been great and revolutionary expeditions as the discovery of America or the periplus of Cape of Good Hope, explorations aimed at reaching the limits that, along the centuries, have lead to more and more engaging scientific discoveries in more and more far away lands, ending only in the twentieth century with the complete mapping of all the continents. Nuclear Physics is living an analogous adventure on the plane of contrast... - Italian: Se lo stato attuale delle conoscenze teoriche e sperimentali della Fisica Nucleare si potesse ridurre a una carta geografica o un mappamondo, allora la nostra epoca si potrebbe paragonare per certi versi alla fine del Medioevo e per altri al Rinascimento: epoche in cui, accanto alla conoscenza consolidata del Vecchio mondo, ci furono grandi e rivoluzionarie spedizioni come la scoperta dell'America o il periplo del Capo di Buona Speranza, esplorazioni geografiche volte al raggiungimento dei limiti che, nel corso dei secoli, hanno portato a scoperte scientifiche sempre pi\`u avvincenti in terre sempre pi\`u lontane, culminate solo nel ventesimo secolo con la completa mappatura di tutte le terre emerse. La Fisica Nucleare sta vivendo un'avventura analoga sul piano della contrapposizione tra la conoscenza acquisita sui nuclei stabili e la scoperta delle sorprendenti propriet\`a esotiche dei nuclei instabili, pi\`u difficili da produrre, da studiare e da comprendere., Comment: 17 pages, 13 figure, in Italian. This paper aims at popularizing the subject of exotic nuclei. - 17 pagine, 13 figure, in Italiano. Questo articolo ha lo scopo di divulgare il tema dei nuclei esotici

The theory of numbers was supposed to be the less useful branch of mathematics. At the same time, cryptography was thought to be a military or a diplomatic issue. In this note we show how the two concepts are today strictly related and how this link affects our daily activities., Comment: 34 pages, in Italian. Extended version of a paper published by the Italian magazine Progetto Alice, 2010-III, Vol. XI, n.33, 427-462

This paper collects some reflections about an apparent incongruity between the usual (third-person) understanding of the probability of an event calculated for an extended period of time in the future (e.g., the expected probability of a driver to meet with a car accident in the next $M$ years) and the subjective perception of the same probability/risk that the person involved in that event has, instant by instant during that period of time. Similarities with the classical Zeno's paradoxes come to mind., Comment: 7 pages, no figures. English translation of v2 (in Italian)

This document was created in order to study the algorithms for the categorization of phrases and rank them using the facilities provided by the framework Apache Spark. Starting from the study illustrated in the publication "Classifying textual data: shallow, deep and ensemble methods" by Laura Anderlucci, Lucia Guastadisegni, Cinzia Viroli, we wanted to carry out a study on the possible realization of a solution that uses the distributed environment and allows the classification of phrases. Italiano. Il presente documento persegue l'obiettivo di studiare gli algoritmi per la categorizzazione di frasi e classificarle con l'ausilio delle strutture messe a disposizione dal framework Apache Spark. Partendo dallo studio illustrato nella pubblicazione "Classifying textual data: shallow, deep and ensemble methods" di Laura Anderlucci, Lucia Guastadisegni e Cinzia Viroli si \`e voluto realizzare uno studio sulla possibile implementazione di una soluzione in grado di classificare frasi sfruttando i l'ambiente distribuito., Comment: in Italian

As part of a large Hubble Space Telescope investigation aiming at reaching the faintest stars in the Galactic globular cluster NGC 6752, an ACS/WFC field was the subject of deep optical observations reaching magnitudes as faint as V~30. In this field we report the discovery of Bedin I a dwarf spheroidal galaxy too faint and too close to the core of NGC 6752 for detection in earlier surveys. As it is of broad interest to complete the census of galaxies in the local Universe, in this Letter we provide the position of this new object along with preliminary assessments of its main param eters. Assuming the same reddening as for NGC 6752, we estimate a distance modulus of (m-M)_0 = 29.70+/-0.13 from the observed red giant branch, i.e., 8.7 (+0.5 -0.7) Mpc, and size of ~840x340pc, about 1/5 the size of the LMC. A comparison of the observed colour-magnitude diagram with synthetic counterparts that account for the galaxy distance modulus, reddening and photometric errors, suggests the presence of an old (~13Gyr) and metal poor ([Fe/H]~-1.3) population. This object is most likely a relatively isolated satellite dwarf spheroidal galaxy of the nearby great spiral NGC 6744, or potentially the most distant isolated dwarf spheroidal known with a secure distance., Comment: 5 pages, 1 table, 3 figures (2 in low resolution). Published on MNRAS Letters and freely available https://academic.oup.com/mnrasl/article/484/1/L54/5288002 Related press releases: https://media.stsci.edu/news_release/news/2019-09 and https://www.spacetelescope.org/news/heic1903/ , (and only in italian: https://www.youtube.com/watch?v=VZCop_j3KOo )

The work presents two algorithms of manipulation and comparison between strings whose purpose is the orthographic recognition of the apostrophe and of the compound expressions. The theory supporting general reasoning refers to the basic concept of EditDistance, the improvements that ensure the achievement of the objective are achieved with the aid of tools borrowed from the use of techniques for processing large amounts of data on distributed platforms., Comment: in Italian

English. This document describes the solutions adopted, which arose from the need to transfer a large amount of information between the most famous distributed SQL and NoSQL storage systems to perform analysis and/or modification operations exploiting the peculiarities of the same. The goal was achieved using the Spark engine and studying and using the open source library "Hive Warehouse Connector" made by Hortonworks. It provides new interoperability features between Hive and Spark. The choice fell on these APIs in order to take advantage from Spark's distributed computing through Spark-Sql libraries, to allow a quick reading and writing on the databases chosen by the Network Contacts Systems Engineering Team and to make the stored information available for consultation outside the Ambari cluster. Italiano. Il presente documento descrive le soluzioni adottate, nate dalla necessit\`a di trasferire un elevato numero di informazioni tra i pi\`u famosi sistemi distribuiti di archiviazione SQL e NoSQL per effettuare operazioni di analisi e/o modifica sfruttando le peculiarit\`a degli stessi. L'obiettivo \`e stato raggiunto utilizzando l'engine Spark e studiando e utilizzando la libreria open source "Hive Warehouse Connector" messa a disposizione da Hortonworks che fornisce nuove funzionalit\`a di interoperabilit\`a tra Hive e Spark. La scelta \`e ricaduta su queste API per poter avvalersi del calcolo distribuito di Spark mediante le librerie di Spark-Sql, per consentire una rapida lettura e scrittura sui database scelti dal team di Ingegneria dei Sistemi di Network Contacts al fine di rendere consultabili le informazioni archiviate all'esterno del cluster Ambari., Comment: in Italian

In Europe (e.g., in Italy), and in the States, the opinion is widely spreading that the negative consequences of modern progress are the fault of "Science". A lively debate on this topic took place among the famous writer Leonardo Sciascia and Italian physicists like Edoardo Amaldi and Emilio Segre', when Sciascia wrote his known book about the disappearance of Ettore Majorana, a book that presented Majorana (a very reserved theoretical physicist) as an example of the scientist that keeps his discoveries secret when afraid of possible evil applications. We wish to contribute now to such a question, since many special meetings did recently return to it, while celebrating the centenary of Majorana's birth (2006), or 30 years (2005) from Sciascia's book publication. It appeared natural to us to start with the figure of Einstein, who, even if extremely peaceable, supported the atomic bomb construction by his letter to Roosvelt. We discuss first the significance of part of Einsteins's scientific work (which flourished in particular one century ago): We seize this opportunity for presenting a derivation of the "twins paradox", so simple that it has been taught to Senior High School last-year students or University undergraduate students; all the present work, more in general, is addressed mainly to them. In the second part of this paper, we analyse the general meaning of Einstein's contributions to philosophy and pedagogy. The third part is entirely devoted to our main subject, i.e., to discussing the "Responsibility of the Intellectuals". The reader interested chiefly in this last part, can find it re-expounded in a self-contained way in the Appendix. More information in the Contents of this article., Comment: Replaced with minor improvements (typoes, one ref. added,...): 53 pages in Italian, with 7 Figures; source-file in Word. [The occasion for writing this work was a wish to prepare material useful to Senior High School last-year students and Univerity undergraduate students]

Plutarchus, circa 100 AD, in his early book on "astrophysics" --in which he exposed, in a sense, a general theory of gravitation-- wrote the noticeable passage: <>. While Posidonius (circa 135-51 BC) had written: <>. These two examples show how "modern" was part of the ancient Greek physics, frequently overlooked since it is sometimes known through the praiseworthy translations of scholars often competent in humanities, more than in science. [A more extended English summary appears at the beginning of this article, which is in Italian.], Comment: 18 pages, in Italian: but with a more extended summary in English. A preliminary version of this paper did already appear in the journal specified below

In this paper we present three simple applications of probability and highlight and discuss their paradoxical flavour., Comment: Plain LaTeX, 9 pages, one figure. Text in Italian

This is a brief, popular (non-technical) introduction (in Italian language) to the problem of quantum gravity, to the recent perspective of emergent spacetime and to its (potential) realization in the context of group field theories, in which the universe emerges as a condensate of non-spatiotemporal constituents., Comment: 15 pages, 12 (color) figures; Ithaca class file; published (in Italian language) on "Ithaca: Viaggio nella Scienza", ISSN: 2282-8079, ESE (Salento University Publishing) - http://ithaca.unisalento.it/nr-12_2018/index.html

A brief introduction to gravitational waves, addressing those questions that nowadays more and more frequently arise within a large audience (not only of insiders): what is a gravity wave, how can it be detected and, above all, what impact on modern physical theories may have their recent discovery? Interested readers can also find a few simple technical details and insights in the final Appendices., Comment: Published (in Italian language) on "Ithaca: Viaggio nella Scienza", ISSN: 2282-8079, ESE (Salento University Publishing), http://ithaca.unisalento.it/nr-12_2018/index.html

English. This document is designed to study the data structures that can be used in the Apache Spark framework and to evaluate the best performing ones to implement solutions, in particular we will evaluate advantages / disadvantages deriving from the use of Dataset for job creation. The observation of the results provides further support in evaluating the use of Dataset as an alternative to RDD, in order to understand its strengths and weaknesses. The examination of the results is possible thanks to specifically designed and implemented in Java 1.8 language. The execution of the jobs, entrusted to a suitable distributed environment, will end with the comparison between execution times and results obtained. Italiano. Il presente documento nasce allo scopo di studiare le strutture dati utilizzabili nel framework Apache Spark e valutare quelle pi\`u performanti per implementare soluzioni; valuteremo in articolare i vantaggi / svantaggi derivanti dall'utilizzo dei Dataset nella progettazione dei job. L'osservazione dei risultati fornisce ulteriore supporto nel valutare l'utilizzo dei Dataset in alternativa a RDD, al fine di comprederne i punti di forza e di debolezza. L'esame dei risultati \`e possibile in virt\`u di due casi appositamente pensati e implementati in linguaggio Java 1.8. L'esecuzione dei job, affidata a un adeguato ambiente distribuito, si concluder\`a con il confronto tra tempi di esecuzione e risultati ottenuti., Comment: in Italian

In this paper we study the Connes amenability of the second dual of Arens regular Banach algebras. Of course we provide a partial answer to the question posed by Volker Runde. Also we fined the necessary and sufficient conditions for the second dual of an Arens regular module extension Banach algebra to be Connes amenable when the module is reflexive., Comment: 5 pages. To appear in Italian J. of Pure and Appl. Math

We report on the retrieval of the last missing papers of the "Senatore folder", given by Majorana to one student of his in Naples in 1938, just before his disappearance. The mentioned manuscript is conserved at the Domus Galilaeana in Pisa (Italy), and was written in French, probably for a conference in Leningrad (or in Kharkov) in 1933 (or in 1934). Majorana was invited to attend to such a conference but, actually, he did not tke part to it. The retrieved text deals with quantum electrodynamics by using the formalism of field quantization. It is here reported, for the first time, in translation. An accurate historical and scientific account is given as well., Comment: 16 pages, latex, amsart, in italian

The paper describes methods used for the detection of cosmic rays with energies above 10^18 eV (UHECR, UltraHigh Energy Cosmic Rays). It had been anticipated there would be a cutoff in the energy spectrum of primary cosmic rays around 3 10^19 eV induced by their interaction with the 2.7 K primordial photons. This has become known as the GZK cutoff. However, several showers have been detected with estimated primary energy exceeding this limit., Comment: 4 pages, 4 figures. To appear in the proceedings of 17th Conference on High Energy Physics (IFAE 2005) (In Italian), Catania, Italy, 30 Mar - 2 Apr 2005

In this paper we develop a simple model of the penetration process of a long rod through an uniform target. Applying the momentum and energy conservation laws, we derive an analytical relation which shows how the penetration depth depends upon the density of the rod, given a fixed kinetic energy. This work was sparked off by the necessity of understanding the effectiveness of high density penetrators (e.g. depleted uranium penetrators) as anti-tank weapons., Comment: 8 pages, 4 figures and 2 tables. Text in Italian

This paper describes the semantics and ideas about SKY, a logic programming language intended in order to specify algorithmic strategies for the evaluation of problems., Comment: In italian

In this article (after some brief theoretical considerations) a bird-eye view is presented -with the help of nine figures- of the various experimental sectors of physics in which Superluminal motions seem to appear. In particular, a panorama is presented of the experiments with evanescent waves and/or tunnelling photons, and with the "localized Superluminal solutions" to the Maxwell equations (e.g., with the so-called X-shaped ones). The present paper is sketchy, but is followed by a large enough bibliography to allow the interested reader deepening the preferred topic., Comment: 12 pages plus 8 figures. A version in Italian, to be requested to the author, is available too

The equable, Pythagorean and natural scales are built on the basis of a mathematical logic., Comment: in Italian

Recently the media broadcast the news, together with illustrative videos, of a so-called Japanese method to perform multiplication by hand without using the multiplication tables. "Goodbye multiplication tables" was the headline of several websites, including important ones, where news are however too often `re-posted' uncritically. The easy numerical examples could induce naive internauts to believe that, in a short future, multiplications could be really done without the knowledge of multiplication tables. This is what a girl expresses, with great enthusiasm, to her father. The dialogues described here, although not real, are likely and have been inspired by this episode, being Maddalena the daughter of the author. Obviously the revolutionary value of the new method is easily disassembled, while its educational utility is highlighted to show (or remember) the reasoning on which the method learned in elementary school is based, although mostly applied mechanically., Comment: 14 pages, 15 figures, in Italian, published in Progetto Alice, Rivista di Matematica e Didattica

Ettore Majorana, perhaps the greatest Italian theoretical physicist of this century (Enrico Fermi compared him to Galilei and Newton), disappeared misteriously from Naples in 1938, when he was 31. In the first part of this work we outline his scientific personality (on the basis of letters, documents, testimonies collected by us in about twenty years) and the significance of some parts of his publications. In the second part of this paper we set forth some brief information about the unpublished scientific manuscripts left by E.Majorana and known to us till this moment (most of which are deposited at the "Domus Galilaeana" in Pisa, Italy), and present a preliminary Catalogue of them prepared in collaboration with M.Baldo and R.Mignani. [The present material is mainly taken from our book "Il Caso Majorana: Epistolario, Documenti, Testimonianze" (Mondadori, Milan, 1987,1991; Di Renzo, Rome, 2000-2008): We address to such a book (c/o www.direnzo.it, "Arcobaleno" series) all the readers interested in more and deeper information; as well as, for more technical topics, to the subsequent volumes reproducing e.g. part of the scientific manuscripts left unpublished by Ettore Majorana: see, for instance, the e-print arXiv:0709.1183v1[physics.hist-ph].], Comment: LaTeX file, in Italian; 81 pages (replaced with some more info on recent literature and about the existing copyrights). A preliminary version of this article appeared in due time in the Journal indicated below

The declination of the Sun along the year varies according to a sinusoid. Around the solstices this curve is approximated by a parabola. In kinematics a parabola is obtained with a constant acceleration. This acceleration has been estimated in the days 21-29 December 2017, from the measurements taken at the meridian line in the Basilica of Santa Maria degli Angeli in Rome made by Francesco Bianchini in 1702 with purpose of measuring the variation of the obliquity of the ecliptic. The parabola equation is fitted to the data to obtain the solstice's instant with an accuracy of one hour. The departure of the measures is within 4 arcsec (the daytime seeing during these solar transits) from the ephemerides of IMCCE. The pipeline of the algorithm used to obtain the angular data of the center of the Sun, starting from the ground measurements affected by the atmospheric refraction, and corrected by the Cassini equation, is described. Bianchini in 1703 reduced the error on the solstices timings by using the difference in right ascension between the Sun and a star observed at the same meridian line even in daytime (as he did with Sirius in June-July 1703). The present one is an absolute measurement, without stellar references. The meridian diameter is averagely measured 24 arcsec less than the true value, with 20 arcsec of standard deviation, because of different luminosity contrasts in the sky and in the Basilica. Conversely the center of the image is much better defined (the contrast acts symmetrically without moving the center of the image), allowing an accuracy to the nearest arcsecond in the determination of the true obliquity., Comment: 9 pages, 2 figure, 4 links to video of the phenomenon. In Italian with extended English abstract

During the last 50 years we have been witness of an extraordinary revolution in the knowledge and understanding of our star thanks to the development of Helioseismology, the study of solar oscillations. Similar to what happens on the Earth during earthquakes, the interior of the Sun is continuously pervaded by seismic waves which produce small oscillations on the photosphere. These oscillations bring the signature of several processes which happen in the interior of the solar structure and the seismic frequencies of the oscillation modes detected on the solar surface are directly related to physical parameters of the internal layers crossed by the seismic waves. The study of oscillations represents, then, the only method to infer directly the internal structure and dynamics of the Sun. This article will present the general characteristics of solar oscillations, the main important results and the advances obtained in stellar physics thanks to the methods of Helioseismology., Comment: in Italian

Around year 2000 the centenary of Planck's thermal radiation formula awakened interest in the origins of quantum theory, traditionally traced back to the Planck's conference on 14 December 1900 at the Berlin Academy of Sciences. A lot of more accurate historical reconstructions, conducted under the stimulus of that recurrence, placed the birth date of quantum theory in March 1905 when Einstein advanced his light quantum hypothesis. Both interpretations are yet controversial, but science historians agree on one point: the emergence of quantum theory from a presumed "crisis" of classical physics is a myth with scarce adherence to the historical truth. This article, written in Italian language, was originally presented in connection with the celebration of the World Year of Phyics 2005 with the aim of bringing these scholarly theses to a wider audience. --- Tradizionalmente la nascita della teoria quantistica viene fatta risalire al 14 dicembre 1900, quando Planck present\`o all'Accademia delle Scienze di Berlino la dimostrazione della formula della radiazione termica. Numerose ricostruzioni storiche pi\`u accurate, effettuate nel periodo intorno al 2000 sotto lo stimolo dell'interesse per il centenario di quell'avvenimento, collocano invece la nascita della teoria quantistica nel marzo del 1905, quando Einstein avanz\`o l'ipotesi dei quanti di luce. Entrambe le interpretazioni sono tuttora controverse, ma gli storici della scienza concordano su un punto: l'emergere della teoria quantistica da una presunta "crisi" della fisica classica \`e un mito con scarsa aderenza alla verit\`a storica. Con questo articolo in italiano, presentato originariamente in occasione delle celebrazioni per il World Year of Phyics 2005, si \`e inteso portare a un pi\`u largo pubblico queste tesi gi\`a ben note agli specialisti., Comment: 11 pages, 2 figures, in Italian, published on Apr. 8, 2005 on the SISSA online magazine "Biblioteca dei 500", ISSN 1722-4306, in website "ULISSE - nella rete della scienza", available at http://ulisse.sissa.it/biblioteca/saggio/2005/Ubib050401s002/at_download/file/Ubib050401s002.pdf (service discontinued as of Jan. 2011)

We suggest a lecture on Newtonian gravity, discussing how the use of the scientific method allows to rule out some of the models for the shape of Earth leaving a spherical Earth as the only possibility, in agreement with empirical observation. In particular, we suggest to focus on a physical quantity, namely the gravitational acceleration, that can be both computed theoretically and measured in experiments. Rather than insisting on the numerical code for the evaluation of the gravitational acceleration -- that can be computed anyway in any numerical analysis course -- we want to focus on the formal setting of the problem, emphasizing the importance of having a mathematical formulation capable of quantitative predictions, present the result and discuss it both qualitatively and quantitatively, comparing it with daily experience. We let the student notice that assuming a non-spherical Earth would result in a parallel component of the gravitational acceleration, in disagreement with measurement; moreover, in case we consider a disk-shaped Earth we show that this parallel component becomes more and more important as the boundaries of Earth are approached by an observer. Finally, we make quantitative predictions on how this abnormal component of the gravitational force would affect the free fall motion. We think that the topics discussed here can be presented both in high school and university classes of general physics, as well as in introductory classes about the scientific method., Comment: Lecture in Italian language, intended to be used in high school and university classes on general physics, as well as in introductory courses on the scientific method. 15 pages, 8 figures, uses gdf latex class

The article describes the algorithm used to define the electricity price in day-ahead and itraday energy markets in Italy. Details of Matlab implementation of one of its simplified versions, capable of producing good results in a extremely short time, are then provided and numerical results are discussed., Comment: in Italian

Sylvester factor, an essential part of the asymptotic formula of Hardy and Littlewood which is the extended Goldbach conjecture, regarded as strongly multiplicative arithmetic function, has several remarkable properties., Comment: 7 pages, in Italian, 4 figures

The research was proposed to exploit and extend the relational and contextual nature of the information assets of the Catasto Gregoriano, kept at the Archivio di Stato in Rome. Developed within the MODEUS project (Making Open Data Effectively Usable), this study originates from the following key ideas of MODEUS: to require Open Data to be expressed in terms of an ontology, and to include such an ontology as a documentation of the data themselves. Thus, Open Data are naturally linked by means of the ontology, which meets the requirements of the Linked Open Data vision., Comment: in Italian

Automatic verification deals with the validation by means of computers of correctness certificates. The related tools, usually called proof assistants or interactive provers, provide an interactive environment for the creation of formal certificates whose correctness can be assessed in a purely automatic way. Such systems have applications both in mathematics, where certificates are proofs of theorems, and in computer science, where certificates testify the correctness of a given software with respect to its specification., Comment: in Italian

In the article, we will report on the recovery of a Melloni's optical bench built at the end of 1800 by the "macchinista" Filippo Caliri in the "belle \'epoque" of Palermo. A scientific instrument of particular historical and didactic interest belonging to the collection of Liceo Classico Statale "Umberto I" of Palermo. In the article, we will discuss the technical aspects of the interventions carried out. In questo articolo discuteremo del recupero di uno strumento scientifico di particolare interesse storico-didattico appartenente alla Collezione del Liceo Classico Statale "Umberto I" di Palermo: un raro banco ottico del Melloni costruito alla fine del 1800 nella Palermo della "belle \'epoque" dal "macchinista" Filippo Caliri. Nell'articolo discuteremo gli aspetti tecnici degli interventi conservativi effettuati., Comment: 10 pages, 5 embedded figures, in Italian language