El pensamiento clásico en la poesía española de hoy: el Platón de los poetas

[ES]La poesía contemporánea, capaz de establecer un diálogo constante con distintas tradiciones y épocas diversas, contiene interesantes lecturas de la filosofía platónica que son rastreables en la obra de autores como Aurora Luque, Chantal Maillard, María Sanz, Josefa Parra o Alberto Tesán y que revitalizan por tanto el pensamiento clásico en la contemporaneidad.

The relation between geometry and matter in classical and quantum gravity and cosmology

The present thesis is divided into two main research areas: Classical Cosmology and (Loop) Quantum Gravity. The first part concerns cosmological models with one phantom and one scalar field, that provide the `super-accelerated' scenario not excluded by observations, thus exploring alternatives to the standard LambdaCDM scenario. The second part concerns the spinfoam approach to (Loop) Quantum Gravity, which is an attempt to provide a `sum-over-histories' formulation of gravitational quantum transition amplitudes. The research here presented focuses on the face amplitude of a generic spinfoam model for Quantum Gravity.

Inverse problems in classical and quantum physics

The subject of this thesis is in the area of Applied Mathematics known as Inverse Problems. Inverse problems are those where a set of measured data is analysed in order to get as much information as possible on a model which is assumed to represent a system in the real world. We study two inverse problems in the fields of classical and quantum physics: QCD condensates from tau-decay data and the inverse conductivity problem. Despite a concentrated effort by physicists extending over many years, an understanding of QCD from first principles continues to be elusive. Fortunately, data continues to appear which provide a rather direct probe of the inner workings of the strong interactions. We use a functional method which allows us to extract within rather general assumptions phenomenological parameters of QCD (the condensates) from a comparison of the time-like experimental data with asymptotic space-like results from theory. The price to be paid for the generality of assumptions is relatively large errors in the values of the extracted parameters. Although we do not claim that our method is superior to other approaches, we hope that our results lend additional confidence to the numerical results obtained with the help of methods based on QCD sum rules. EIT is a technology developed to image the electrical conductivity distribution of a conductive medium. The technique works by performing simultaneous measurements of direct or alternating electric currents and voltages on the boundary of an object. These are the data used by an image reconstruction algorithm to determine the electrical conductivity distribution within the object. In this thesis, two approaches of EIT image reconstruction are proposed. The first is based on reformulating the inverse problem in terms of integral equations. This method uses only a single set of measurements for the reconstruction. The second approach is an algorithm based on linearisation which uses more then one set of measurements. A promising result is that one can qualitatively reconstruct the conductivity inside the cross-section of a human chest. Even though the human volunteer is neither two-dimensional nor circular, such reconstructions can be useful in medical applications: monitoring for lung problems such as accumulating fluid or a collapsed lung and noninvasive monitoring of heart function and blood flow.

Classical limit of the Nelson model

Since the development of quantum mechanics it has been natural to analyze the connection between classical and quantum mechanical descriptions of physical systems. In particular one should expect that in some sense when quantum mechanical effects becomes negligible the system will behave like it is dictated by classical mechanics. One famous relation between classical and quantum theory is due to Ehrenfest. This result was later developed and put on firm mathematical foundations by Hepp. He proved that matrix elements of bounded functions of quantum observables between suitable coherents states (that depend on Planck's constant h) converge to classical values evolving according to the expected classical equations when h goes to zero. His results were later generalized by Ginibre and Velo to bosonic systems with infinite degrees of freedom and scattering theory. In this thesis we study the classical limit of Nelson model, that describes non relativistic particles, whose evolution is dictated by Schrödinger equation, interacting with a scalar relativistic field, whose evolution is dictated by Klein-Gordon equation, by means of a Yukawa-type potential. The classical limit is a mean field and weak coupling limit. We proved that the transition amplitude of a creation or annihilation operator, between suitable coherent states, converges in the classical limit to the solution of the system of differential equations that describes the classical evolution of the theory. The quantum evolution operator converges to the evolution operator of fluctuations around the classical solution. Transition amplitudes of normal ordered products of creation and annihilation operators between coherent states converge to suitable products of the classical solutions. Transition amplitudes of normal ordered products of creation and annihilation operators between fixed particle states converge to an average of products of classical solutions, corresponding to different initial conditions.

Studies on the dual in Mycenaean, in the Homeric poetry and in the Attic Theatre of the 5th century — morphological, dialectal and stylistical variations

The present dissertation focuses on the dual number in Ancient Greek in a diachronical lapse stretching from the Mycenaean age to the Attic Drama and Comedy of the 5th century BC. In the first chapter morphological issues are addressed, chiefly in a comparative perspective. The Indo European evidence on the dual is hence gathered in order to sketch patterns of grammaticalisation and paradigmatisation of specific grams, growing increasingly functional within the Greek domain. In the second chapter syntactical problems are tackled. After a survey of scholarly literature on the Greek dual, we engage in a functional and typological approach, in order to disentangle some biased assessments on the dual, namely its alleged lack of regularity and intermittent agreement. Some recent frameworks in General Linguistics provide useful grounds for casting new light on the subject. Internal Reconstruction, for instance, supports the facultativity of the dual in each and every stage of its development; Typology and the Animacy Hierarcy add precious cross linguistical insight on the behaviour of the dual toward agreement. Glaring differences also arise as to the adoption — or avoidance — of the dual by different authors. Idiolectal varieties prove in fact conditioned by stylistical and register necessity. By means of a comparison among Epics, Tragedy and Comedy it is possible to enhance differences in the evaluation of the dual, which led sometimes to forms of ‘censure’ — thus triggering the onset of competing strategies to express duality. The last two chapters delve into the tantalising variety of the Homeric evidence, first of all in an account of the notorious issue of the Embassy of Iliad IX, and last in a commentary of all significant Homeric duals — mostly represented by archaisms, formulae, and ad hoc coinages.

Coarse-graining and quantum-classical adaptive coupling in soft matter

Die vorliegende Arbeit untersucht den Zusammenhang zwischen Skalen in Systemen weicher Materie, der für Multiskalen-Simulationen eine wichtige Rolle spielt. Zu diesem Zweck wurde eine Methode entwickelt, die die Approximation der Separierbarkeit von Variablen für die Molekulardynamik und ähnliche Anwendungen bewertet. Der zweite und größere Teil dieser Arbeit beschäftigt sich mit der konzeptionellen und technischen Erweiterung des Adaptive Resolution Scheme'' (AdResS), einer Methode zur gleichzeitigen Simulation von Systemen mit mehreren Auflösungsebenen. Diese Methode wurde auf Systeme erweitert, in denen klassische und quantenmechanische Effekte eine Rolle spielen.rnrnDie oben genannte erste Methode benötigt nur die analytische Form der Potentiale, wie sie die meisten Molekulardynamik-Programme zur Verfügung stellen. Die Anwendung der Methode auf ein spezielles Problem gibt bei erfolgreichem Ausgang einen numerischen Hinweis auf die Gültigkeit der Variablenseparation. Bei nicht erfolgreichem Ausgang garantiert sie, dass keine Separation der Variablen möglich ist. Die Methode wird exemplarisch auf ein zweiatomiges Molekül auf einer Oberfläche und für die zweidimensionale Version des Rotational Isomer State (RIS) Modells einer Polymerkette angewandt.rnrnDer zweite Teil der Arbeit behandelt die Entwicklung eines Algorithmus zur adaptiven Simulation von Systemen, in denen Quanteneffekte berücksichtigt werden. Die Quantennatur von Atomen wird dabei in der Pfadintegral-Methode durch einen klassischen Polymerring repräsentiert. Die adaptive Pfadintegral-Methode wird zunächst für einatomige Flüssigkeiten und tetraedrische Moleküle unter normalen thermodynamischen Bedingungen getestet. Schließlich wird die Stabilität der Methode durch ihre Anwendung auf flüssigen para-Wasserstoff bei niedrigen Temperaturen geprüft.

The Bible in Medieval Love Lyrics: A Fundamental Element of European Poetry Books

The focus of this study is the relationship among three different manuscripts (Modena, Bibl. Estense, MS α.R.4.4; Firenze, Bibl. Laurenziana MS Rediano 9; and London, BL, MS Harley, 2253) and the poetry they transmit. The aim of this research is to show the ways that the Bible was used in the transmission of the lyric poetry in the three literatures that they represent: Occitan (primarily through Marcabru’s songs), Italian (through the love poetry of Guittone d’Arezzo), and Middle English (through the Harley love lyrics and the MS.’s primary scribe), in a medieval European context.

L'immagine di Roma nella cultura russa tra fine XVIII secolo e inizio XIX secolo

Nella tesi si osserva come nella cultura russa cambiava l’immagine di Roma. Se ancora alla fine del settecento l’antichità romana poteva risultare solamente uno strumento retorico-filologico da utilizzare per fare il proprio discorso più convincente, la generazione dei decabristi la stessa antica romanità la accostava alla cultura e storia russe tramite gli elevati ideali civici. La romanità ora risultava uno strumento di analisi della esperienza storica e politica della Russia anche nel contesto europeo. Da qui nasceva una serie di modelli russi legati all’antica Roma: il Catone di Radiscev, il Bruto dei decabristi, ecc. Vi attingeva generosamente anche una corrente di lirica russo-antica con i suoi ricchi riferimenti agli autori classici, Ovidio, Tacito, Orazio. Nasceva così una specie di Roma antica russa che viveva secondo le sue regole etiche ed estetiche. Con il fallimento dell’esperienza decabrista cambia anche l’approccio alle antichità: ci si distacca dalla visione storico-morale dell’antico, Roma non è più una categoria da emulare, ma una storia a sé stante e chiusa in sé stessa come ogni periodo storico. Essa smette di essere un criterio universale di giudizio etico e morale. Allo stesso tempo, una parte integrante della cultura russa all’epoca era il viaggio a Roma. I russi cresciuti con interesse e amore verso la Roma antica, impazienti ed emozionati, desideravano ora di vedere quella patria dei classici. Era come se fosse un appuntamento fra gli amici di vecchia data. Si affrettava a verificare di persona le muse di storia e di poesia. E con tutto questo si imparavano ad amare tutti i defetti della Roma reale, spesso inospitale, la Roma del dolore e della fatica. La voce importante nel racconto romano dei russi era anche la Roma del cristianesimo, dove ritrovare e ricoprire la propria “anima cristiana”.

Classical and quantum aspects of black hole dynamics

Il contenuto fisico della Relatività Generale è espresso dal Principio di Equivalenza, che sancisce l'equivalenza di geometria e gravitazione. La teoria predice l'esistenza dei buchi neri, i più semplici oggetti macroscopici esistenti in natura: essi sono infatti descritti da pochi parametri, le cui variazioni obbediscono a leggi analoghe a quelle della termodinamica. La termodinamica dei buchi neri è posta su basi solide dalla meccanica quantistica, mediante il fenomeno noto come radiazione di Hawking. Questi risultati gettano una luce su una possibile teoria quantistica della gravitazione, ma ad oggi una simile teoria è ancora lontana. In questa tesi ci proponiamo di studiare i buchi neri nei loro aspetti sia classici che quantistici. I primi due capitoli sono dedicati all'esposizione dei principali risultati raggiunti in ambito teorico: in particolare ci soffermeremo sui singularity theorems, le leggi della meccanica dei buchi neri e la radiazione di Hawking. Il terzo capitolo, che estende la discussione sulle singolarità, espone la teoria dei buchi neri non singolari, pensati come un modello effettivo di rimozione delle singolarità. Infine il quarto capitolo esplora le ulteriori conseguenze della meccanica quantistica sulla dinamica dei buchi neri, mediante l'uso della nozione di entropia di entanglement.

Soundward: Analisi e traduzione di una selezione di brani della jazz poetry

La letteratura e la musica hanno da sempre condiviso molti aspetti del processo creativo. Questa affinità intellettuale si è più volte espressa attraverso la produzione di opere che si incontrano a metà strada tra le due arti. All'interno di queste occorrenze si è delineata una frangia letteraria, la Jazz Poetry, che trova nel jazz e nei suoi esponenti le proprie muse. Questo lavoro analizza il fenomeno della Jazz Poetry e propone le traduzioni dall'inglese all'italiano di alcune opere esemplificative. Per essere in grado di affrontare questa sfida adeguatamente, la prima parte della tesi verte sullo studio di alcuni punti cardine della traduzione poetica e sulla costruzione di una cornice storico-culturale. All'interno di questa cornice viene analizzato il ruolo del jazz e della Jazz Poetry all'interno della società, con particolare focus sulla sua posizione rispetto ad alcune tematiche di rilievo del Novecento. Vengono evidenziati i principali autori e le distinte genesi storico-letterarie che hanno contribuito alla formazione di questo movimento. Nella seconda parte viene presentata al lettore la traduzione e la successiva analisi dei brani scelti. I sei testi sono stati divisi in due sottocategorie: la poetica di Kaufman e i Coltrane Poems. In entrambe le categorie un breve capitolo introduttivo evidenzia le tematiche affrontate e la rilevanza della cornice storico-sociale all'interno dei testi. Dopo ogni traduzione viene fornita un'analisi approfondita del testo e delle scelte operate a livello traduttivo, comprensiva di un'esegesi del brano. In linea di massima si è cercato di riprodurre il continuo dialogo tra il poeta e il soggetto poetico, sia esso musica o musicista, mantenendo un equilibrio costante tra la potenzialità orale e la realtà scritta del testo.

Computed tomography (CT) virtual autopsy and classical autopsy discrepancies: radiologist's error or a demonstration of post-mortem multi-detector computed tomography (MDCT) limitation?

Modern imaging technologies, such as computed tomography (CT) techniques, represent a great challenge in forensic pathology. The field of forensics has experienced a rapid increase in the use of these new techniques to support investigations on critical cases, as indicated by the implementation of CT scanning by different forensic institutions worldwide. Advances in CT imaging techniques over the past few decades have finally led some authors to propose that virtual autopsy, a radiological method applied to post-mortem analysis, is a reliable alternative to traditional autopsy, at least in certain cases. The authors investigate the occurrence and the causes of errors and mistakes in diagnostic imaging applied to virtual autopsy. A case of suicide by a gunshot wound was submitted to full-body CT scanning before autopsy. We compared the first examination of sectional images with the autopsy findings and found a preliminary misdiagnosis in detecting a peritoneal lesion by gunshot wound that was due to radiologist's error. Then we discuss a new emerging issue related to the risk of diagnostic failure in virtual autopsy due to radiologist's error that is similar to what occurs in clinical radiology practice.