Search results for "CASI"
showing 10 items of 203 documents
Dispersion Interaction between Two Hydrogen Atoms in a Static Electric Field
2019
We consider the dispersion interaction between two ground-state hydrogen atoms, interacting with the quantum electromagnetic field in the vacuum state, in the presence of an external static electric field, both in the nonretarded and in the retarded Casimir-Polder regime. We show that the presence of the external field strongly modifies the dispersion interaction between the atoms, changing its space dependence. Moreover, we find that, for specific geometrical configurations of the two atoms with respect to the external field and/or the relative orientation of the fields acting on the two atoms, it is possible to change the character of the dispersion force, turning it from attractive to re…
Vacuum local and global electromagnetic self-energies for a point-like and an extended field source
2013
We consider the electric and magnetic energy densities (or equivalently field fluctuations) in the space around a point-like field source in its ground state, after having subtracted the spatially uniform zero-point energy terms, and discuss the problem of their singular behavior at the source's position. We show that the assumption of a point-like source leads, for a simple Hamiltonian model of the interaction of the source with the electromagnetic radiation field, to a divergence of the renormalized electric and magnetic energy density at the position of the source. We analyze in detail the mathematical structure of such singularity in terms of a delta function and its derivatives. We als…
Spatial correlations of field observables in two half-spaces separated by a movable perfect mirror
2023
We consider a system of two cavities separated by a reflecting boundary of finite mass that is free to move, and bounded to its equilibrium position by a harmonic potential. This yields an effective mirror-field interaction, as well as an effective interaction between the field modes mediated by the movable boundary. Two massless scalar fields are defined in each cavity. We consider the second-order interacting ground state of the system, that contains virtual excitations of both mirror's degrees of freedom and of the scalar fields. We investigate the correlation functions between field observables in the two cavities, and find that the squared scalar fields in the two cavities, in the inte…
Usi pubblici e politici di Dante Alighieri
2022
The commemorations of Dante Alighieri ‘s 700th death anniversary saw in 2021 a ‘national’ and even a ‘nationalist ‘ Dante cropping up once again in the Italian public discourse. This article summarises the history of the public and political uses of the poet of the Divina Commedia: from the end of the 18th century, when his modern cult was born, to the Risorgimento, from the First World War to Fascism, up to the more recent ‘pop’ Dante.
Mitigating-casi: relation between propositional content and discourse units
2018
El aproximativo casi entraña la inversión polar de su proposición, sin embargo, los usos considerados expletivos presentan valores atenuantes. Este trabajo complementa con un estudio de corpus la descripción teórica del uso expletivo-atenuante en relación con la unidad discursiva de casi en el habla coloquial. La unidad que ocupa en el discurso determina su uso atenuante y supone una prueba efectiva de su naturaleza semántica, al tiempo que aclara ciertas cuestiones de la bibliografía deductiva. This paper explores the mitigating function of Spanish casi and its relation to the discourse units casi fulfills in spoken language. Casi can either entail a polar inversion of the proposition it h…
Bundle generation for last-mile delivery with occasional drivers
2022
In this paper, we present the vehicle routing problem (VRP) with occasional drivers (OD) and order bundles (OB). The problem VRP-OD-OB is an extension of the VRP-OD, where instead of assigning one customer per driver, drivers are assigned bundles of customers. To deal with the bundle-to-driver assignment, a bidding system is exploited, in which a company offers a set of bundles and the drivers raise their bids. These bids depend on features such as the drivers’ destination, flexibility in deviating from the shortest path, and willingness to offer service. To generate valuable bundles of customers, we propose two strategies: (i) an innovative approach based on the creation of corridors, and …
Nota a Cass. 12 dicembre 2019, n. 50340, S., in materia di lancio di materiale pericoloso in occasione di manifestazioni sportive, concorso morale e …
2020
La sentenza in epigrafe si segnala all'attenzione per aver precisato i criteri che consentono di distinguere le fattispecie di attentato alla sicurezza pubblica di cui all'art. 6 l. n. 895 del 1967, così come novellata dall'art. 13 l. n. 497 del 1974, e quella di «lancio di materiale pericoloso, scavalcamento ed invasione di campo in occasione di manifestazioni sportive», disciplinata dall'art. 6 bis l. n. 401 del 1989. Con essa, inoltre, la Suprema Corte torna a fare il punto, rispettivamente, sul tema del concorso morale e sui presupposti della continuazione.
Des lieux et des liens : du décentrement à l’engagement dans la poésie de Laura Casielles
2023
Laura Casielles (Pola de Siero, Asturies, 1986) est une poétesse, traductrice et journaliste espagnole. Cartes, paysages, territoires peuplent son écriture poétique qui affiche un souci de l’autre lieu et de l’autre langue. Cet article s’intéresse plus particulièrement aux recueils Los idiomas comunes et Las señales que hacemos en los mapas. Deux ouvrages qui invitent à « aller voir ailleurs » : dans le premier recueil, un « ailleurs » qui est un au-delà de soi, pour explorer ainsi les espaces des « communs » ; et, dans le deuxième recueil, un « ailleurs » vers d’autres territoires pour penser la question de l’enclosure identitaire et des enracinements. La notion d’« ailleurs » est égalemen…
Discrete KP Equation and Momentum Mapping of Toda System
2003
Abstract A new approach to discrete KP equation is considered, starting from the Gelfand-Zakhharevich theory for the research of Casimir function for Toda Poisson pencil. The link between the usual approach through the use of discrete Lax operators, is emphasized. We show that these two different formulations of the discrete KP equation are equivalent and they are different representations of the same equations. The relation between the two approaches to the KP equation is obtained by a change of frame in the space of upper truncated Laurent series and translated into the space of shift operators.
Navigare a vela, tra storia e contemporaneità, in una città di luce
2015
Il contributo mette a confronto Lisbona e Palermo, analizzando le trasformazioni della citta' portoghese e le occasioni perdute della "capitale" siciliana. A partire da alcune analogie, infatti, le due città hanno vissuto stagioni assai differenti, a Lisbona sono state condotte politiche tese a rendere la città competitiva e a dotarla di servizi di eccellenza nonché di progetti di architettura contemporanea; a Palermo la situazione, analizzata sulla scorta delle ultime vicende politiche, appare assai diversa.