270 research outputs found

    Dark energy, cosmological constant and neutrino mixing

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    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

    Understanding flavor mixing in Quantum Field Theory

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    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

    Group theoretical aspects of neutrino mixing in Quantum Field Theory

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    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

    A new perspective in the dark energy puzzle from particle mixing phenomenon

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    We report on recent results on particle mixing and oscillations in quantum field theory. We discuss the role played in cosmology by the vacuum condensate induced by the neutrino mixing phenomenon. We show that it can contribute to the dark energy of the universe.Comment: 11 pages, to be published on the review book "Dark Energy-Current Advances and Ideas

    Terraced landscapes located in areas of great value for touristic purposes as an irreversible practice

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    Since Neolithic, terraced landscapes have been an essential element for moulding mountain or steep slope into habitable arable areas. Over the last decades, they have been subjected to a quick abandonment because of their inadequate economic competitiveness causing a gap in their maintenance and, consequently, incrementing the hydrogeological instability of those areas. Minori is a small municipality (256 ha), protected by UNESCO, located in Amalfi Coast. That area is well known not only for the beauty of its territory but also for some catastrophic raining events, like in 1954 when a rain shower of 500 mm topped up to 24 hours. The current research work intends to analyse the landscape changes in Minori over sixty year period (1956 - 2017) for assessing the new values taken on the land use and the agricultural sites. A detailed orthophoto and a high resolution Digital Elevation Model (DEM) of the study area have been reconstructed using the historical photogrammetric photos of 1954, acquired by the Italian Military Geographic Institute (IGM), and the aerial photogrammetric pictures of 2017, obtained by an own flight. DEM and orthophoto have been reconstructed applying Agisoft Photoscan Professional. The resolution of the generated DEM is equal to 0.48 and 0.1 m for 1956 and 2017, respectively. The orthophoto resolution is of 0.24 and 0.07 for 1956 and 2017, respectively. Comparing the generated products of the two periods, it is pointed out that terraces extension has not been amended, while the amount of human constructions have increased of about 800%. To give a first idea of the most vulnerable areas to be investigated more in depth through simulation procedures, a first proposal of an expeditious index of vulnerability (EVI) has been introduced and tested. It is based on the ratio between the amount of surface occupied by buildings and the amount of areas subjected to a debris flow event. The increase of the vulnerability, exposure values and probability of accident occurring involve a risk rise

    Geometric phase and gauge theory structure in quantum computing

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    We discuss the presence of a geometrical phase in the evolution of a qubit state and its gauge structure. The time evolution operator is found to be the free energy operator, rather than the Hamiltonian operator.Comment: 5 pages, presented at Fifth International Workshop DICE2010: Space-Time-Matter - current issues in quantum mechanics and beyond, Castiglioncello (Tuscany), September 13-17, 201

    Dark energy induced by neutrino mixing

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    The energy content of the vacuum condensate induced by the neutrino mixing is interpreted as dynamically evolving dark energy.Comment: 5 pages, Presented at 3nd International Workshop DICE 2006: Quantum Mechanics between Decoherence and Determinism: new aspects from particle physics to cosmology, September 11-15, 200

    Probing quantum field theory particle mixing and dark-matter-like effects with Rydberg atoms

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    Abstract We analyze the oscillations of Rydberg atoms in the framework of quantum field theory and analyze the analogy with flavor mixing and oscillations. We reveal a non trivial vacuum energy which has the equation of state analogous to that of cold dark matter. This energy is formally similar to that expected for mixed neutrinos and affects the thermal capacity of the gas. Therefore, deflection of the thermal capacity of Rydberg atoms could prove the condensate structure of vacuum for mixing fermions and open new scenarios in the study of the dark components of the universe. We also derive new Rabi oscillation formulae which are, in principle, testable experimentally

    Flavor states of mixed neutrinos

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    By resorting to previous results on flavor mixing in Quantum Field Theory, we show how to consistently define flavor states of mixed neutrinos as eigenstates of the flavor charge operators.Comment: 4 pages, presented at 13th International Symposium on Particles, Strings and Cosmology, PASCOS-07, 2-7 July 2007, Imperial College Londo
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