Understanding flavor mixing in Quantum Field Theory

We report on recent results showing that a rich non-perturbative vacuum structure is associated with flavor mixing in Quantum Field Theory. We treat explicitly the case of mixing among three generations of Dirac fermions. Exact oscillation formulas are presented exhibiting new features with respect to the usual ones. CP and T violation are also discussed.Comment: 9 pages. Presented at the "International Conference on Flavor Physics", Zhang-Jia-Jie, China, May 31 - June 6 200

Dark energy, cosmological constant and neutrino mixing

The today estimated value of dark energy can be achieved by the vacuum condensate induced by neutrino mixing phenomenon. Such a tiny value is recovered for a cut-off of the order of Planck scale and it is linked to the sub eV neutrino mass scale. Contributions to dark energy from auxiliary fields or mechanisms are not necessary in this approach.Comment: 10 pages, 2 figure

Quantization of scalar fields in curved background, deformed Hopf algebra and entanglement

A suitable deformation of the Hopf algebra of the creation and annihilation operators for a complex scalar field, initially quantized in Minkowski space--time, induces the canonical quantization of the same field in a generic gravitational background. The deformation parameter q turns out to be related to the gravitational field. The entanglement of the quantum vacuum appears to be robust against interaction with the environment.Comment: 4 pages, to appear in Proceedings of the XXIV International Colloquium on Group Theoretical Methods in Physics, Paris, 14-21 July 200

Interoperable services based on activity monitoring in ambient assisted living environments

Ambient Assisted Living (AAL) is considered as the main technological solution that will enable the aged and people in recovery to maintain their independence and a consequent high quality of life for a longer period of time than would otherwise be the case. This goal is achieved by monitoring human’s activities and deploying the appropriate collection of services to set environmental features and satisfy user preferences in a given context. However, both human monitoring and services deployment are particularly hard to accomplish due to the uncertainty and ambiguity characterising human actions, and heterogeneity of hardware devices composed in an AAL system. This research addresses both the aforementioned challenges by introducing 1) an innovative system, based on Self Organising Feature Map (SOFM), for automatically classifying the resting location of a moving object in an indoor environment and 2) a strategy able to generate context-aware based Fuzzy Markup Language (FML) services in order to maximize the users’ comfort and hardware interoperability level. The overall system runs on a distributed embedded platform with a specialised ceiling- mounted video sensor for intelligent activity monitoring. The system has the ability to learn resting locations, to measure overall activity levels, to detect specific events such as potential falls and to deploy the right sequence of fuzzy services modelled through FML for supporting people in that particular context. Experimental results show less than 20% classification error in monitoring human activities and providing the right set of services, showing the robustness of our approach over others in literature with minimal power consumption

Group theoretical aspects of neutrino mixing in Quantum Field Theory

By resorting to recent results on the Quantum Field Theory of mixed particles, we discuss some aspects of three flavor neutrino mixing. Particular emphasis is given to the related algebraic structures and their deformation in the presence of CP violation. A novel geometric phase related to CP violation is introduced.Comment: 10 pages, 2 figures. Presented at the XII International Baksan School "Particles and Cosmology", Baksan Valley, Kabardino-Balkaria, Russian Federation - April 21 - 26, 200

QUANTUM DISSIPATION AND QUANTUM NOISE

We derive the exact action for a damped mechanical system ( and the special case of the linear oscillator) from the path integral formulation of the quantum Brownian motion problem developed by Schwinger and by Feynman and Vernon. The doubling of the phase-space degrees of freedom for dissipative systems and thermal field theories is discussed and the initial values of the doubled variables are related to quantum noise effects.Comment: This is a Tex file; To be published in Annals of Phys. (N.Y.) 238, 200 (1995

Green's Functions for Neutrino Mixing

The Green's function formalism for neutrino mixing is presented and the exact oscillation formula is obtained. The usual Pontecorvo formula is recovered in the relativistic limit.Comment: 4 pages, LaTeX (need sprocl.sty). To appear in the Proceedings of the 6th International Symposium on Particles, Strings and Cosmology (PASCOS 98), Boston, 22-27 March 199