Search results for " witnesses"
showing 8 items of 8 documents
Two-qubit entanglement dynamics for two different non-Markovian environments
2009
We study the time behavior of entanglement between two noninteracting qubits each immersed in its own environment for two different non-Markovian conditions: a high-$Q$ cavity slightly off-resonant with the qubit transition frequency and a nonperfect photonic band-gap, respectively. We find that revivals and retardation of entanglement loss may occur by adjusting the cavity-qubit detuning, in the first case, while partial entanglement trapping occurs in non-ideal photonic-band gap.
Krytyka wybranych aspektów chrystologii świadków Jehowy w świetle książki Josepfa Ratzingera: Jezus z Nazaretu, cz. I: Od chrztu w Jordanie do Przemi…
2018
Pytanie Chrystusa zawarte we wszystkich ewangeliach synoptycznych: za kogo uważają Go ludzie i kim On jest dla apostołów, wydaje się być wciąż aktualne. Papież Benedykt XVI określa je jako „kamień milowy na drodze Jezusa”. Mimo rozwoju nauk humanistycznych, odpowiedzi jest wiele, a często są one sprzeczne. Niniejsza praca stanowi próbę krytyki wybranych elementów chrystologii świadków Jehowy w świetle obrazu Chrystusa ujętego w książce Josepha Ratzingera Jezus z Nazaretu, cz. I: Od chrztu w Jordanie do Przemienienia. Powyższe zestawienie wykazało, jak liczne i poważne są rozbieżności w postrzeganiu Jezusa przez organizację oraz Jego przedstawieniu w Biblii. Fakty te przemawiają za konieczno…
Entanglement dynamics in superconducting qubits affected by local bistable impurities
2012
We study the entanglement dynamics for two independent superconducting qubits each affected by a bistable impurity generating random telegraph noise (RTN) at pure dephasing. The relevant parameter is the ratio $g$ between qubit-RTN coupling strength and RTN switching rate, that captures the physics of the crossover between Markovian and non-Markovian features of the dynamics. For identical qubit-RTN subsystems, a threshold value $g_\mathrm{th}$ of the crossover parameter separates exponential decay and onset of revivals; different qualitative behaviors also show up by changing the initial conditions of the RTN. We moreover show that, for different qubit-RTN subsystems, when both qubits are …
Dynamics of correlations due to a phase noisy laser
2012
We analyze the dynamics of various kinds of correlations present between two initially entangled independent qubits, each one subject to a local phase noisy laser. We give explicit expressions of the relevant quantifiers of correlations for the general case of single-qubit unital evolution, which includes the case of a phase noisy laser. Although the light field is treated as classical, we find that this model can describe revivals of quantum correlations. Two different dynamical regimes of decay of correlations occur, a Markovian one (exponential decay) and a non-Markovian one (oscillatory decay with revivals) depending on the values of system parameters. In particular, in the non-Markovia…
Hierarchy and dynamics of trace distance correlations
2013
We define and analyze measures of correlations for bipartite states based on trace distance. For Bell diagonal states of two qubits, in addition to the known expression for quantum correlations using this metric, we provide analytic expressions for the classical and total correlations. The ensuing hierarchy of correlations based on trace distance is compared to the ones based on relative entropy and Hilbert-Schmidt norm. Although some common features can be found, the trace distance measure is shown to differentiate from the others in that the closest uncorrelated state to a given bipartite quantum state is not given by the product of the marginals, and further, the total correlations are s…
Mafiosi, politici, pentiti
2007
La ricerca sociologica in tema di criminalità organizzata di tipo mafioso, si caratterizza per un vuoto teorico che riguarda la figura dei collaboratori di giustizia. Personaggi ingombranti per tutti – per i magistrati, per i politici, per i mafiosi irriducibili, per i loro stessi familiari – sembra che per gli ex-uomini d’onore non vi siano possibilità di reinserimento in una condizione di vita normale. Nonostante la loro riconosciuta utilità, difficilmente si riesce a non considerarli ancora come mafiosi e a non nutrire nei loro confronti perplessità e sospetti. Questo, e altro, emerge dai risultati di una indagine sulla percezione sociale dei collaboratori di giustizia in Sicilia, che me…
L’innovazione tecnologica e il Faculty Development.
2023
La crisi pandemica ha accelerato la diffusione di ambienti di apprendimento caratterizzati dall'uso intensivo della tecnologia. Questa novità rappresenta un obiettivo trasversale della professionalizzazione del docente universitario, con una particolare declinazione sul versante pedagogico-didattico-valutativo quale questione strategica per lo sviluppo dell’alta formazione. Il contributo illustra i risultati di una ricerca condotta con 119 docenti universitari neoassunti e 20 Direttori di dipartimento. La finalità della ricerca è stata, da una parte, rilevare la percezione dei docenti neoassunti relativa alle proprie competenze didattiche, metacognitive e valutative, con riferimento alla di…
Dan v. Moldavia 2: la rinnovazione in appello tra itinerari sperimentati e cedimenti silenziosi
2020
After several years, the European Court of Human Rights comes back on the case of Dan v. Moldova: a judgment that has had a significant impact on our appeal process. The key question is whether a new shock wave is to be expected by this further ruling.