Seismic scattering and absorption mapping from intermediate-depth earthquakes reveals complex tectonic interactions acting in the Vrancea region and surroundings (Romania)

The present study was performed during a stay at the University of Münster financed by a grant awarded by the German Academic Exchange Service (DAAD) in 2014. Data used in the present study were provided by the National Institute for Earth Physics (Romania) and processed within the National Data Centre in Magurele. Seismic Analysis Code (SAC) (Goldstein and Snoke, 2005) and GMT (Wessel et al., 2013) codes were used. We thank the College of Physical Sciences (University of Aberdeen) and the Santander Mobility Award for providing travel grant to LDS to complete this manuscript. We are grateful as well to the anonymous reviewer for his useful remarks which helped us to improve the paper.Peer reviewedPostprin

Quantum Groups, Coherent States, Squeezing and Lattice Quantum Mechanics

By resorting to the Fock--Bargmann representation, we incorporate the quantum Weyl--Heisenberg ($q$-WH) algebra into the theory of entire analytic functions. The main tool is the realization of the $q$--WH algebra in terms of finite difference operators. The physical relevance of our study relies on the fact that coherent states (CS) are indeed formulated in the space of entire analytic functions where they can be rigorously expressed in terms of theta functions on the von Neumann lattice. The r\^ole played by the finite difference operators and the relevance of the lattice structure in the completeness of the CS system suggest that the $q$--deformation of the WH algebra is an essential tool in the physics of discretized (periodic) systems. In this latter context we define a quantum mechanics formalism for lattice systems.Comment: 22 pages, TEX file, DFF188/9/93 Firenz

Influence of trapping potentials on the phase diagram of bosonic atoms in optical lattices

We study the effect of external trapping potentials on the phase diagram of bosonic atoms in optical lattices. We introduce a generalized Bose-Hubbard Hamiltonian that includes the structure of the energy levels of the trapping potential, and show that these levels are in general populated both at finite and zero temperature. We characterize the properties of the superfluid transition for this situation and compare them with those of the standard Bose-Hubbard description. We briefly discuss similar behaviors for fermionic systems.Comment: 4 pages, 3 figures; final version, to be published in Phys. Rev.

Determination of ground state properties in quantum spin systems by single qubit unitary operations and entanglement excitation energies

We introduce a method for analyzing ground state properties of quantum many body systems, based on the characterization of separability and entanglement by single subsystem unitary operations. We apply the method to the study of the ground state structure of several interacting spin-1/2 models, described by Hamiltonians with different degrees of symmetry. We show that the approach based on single qubit unitary operations allows to introduce {\it ``entanglement excitation energies''}, a set of observables that can characterize ground state properties, including the quantification of single-site entanglement and the determination of quantum critical points. The formalism allows to identify the existence and location of factorization points, and a purely quantum {\it ``transition of entanglement''} that occurs at the approach of factorization. This kind of quantum transition is characterized by a diverging ratio of excitation energies associated to single-qubit unitary operations.Comment: To appear in Phys. Rev.

The Importance of Place Names in the Sustainable Tourist Development of the Inland Areas of Tuscany : Toponyms along the Via Francigena

The study of place names, through appropriate both linguistic and geographical tools (topographic I.G.M. maps; Environmental Information System of Regione Toscana, etc.) makes come up hidden identities in geographical areas that can be exploited because of their cultural heritage or their landscape. Sometimes the discovery of old linguistic remains is essential to understand the meaning and the role of places and of buildings linked to a past living of some ethnic groups who unconsciously let somewhere their marks. The Italian Peninsula is rich in particular place names, due to the passage of people both from the North and from the Mediterranean Sea in different periods and for different purposes. In Tuscany, too, some areas do exist which have a cultural heritage depending on ancestral presences that can be still revealed: the study of toponyms, in fact, is an effective way to understand the origins and the role of places, the interaction between man and the territories where he lived, the historical and geographical changes. Toponyms are able to let us understand the identity and the uniqueness of a place, reveal us the sense of place and build a cultural base in order to make local institutions awere of it, bringing them to apply for a valorization of economically weak regions. In particular we will deal with the path of Via Francigena in Tuscany, between Lunigiana and Val d’Orcia, where we find some economic important areas since their origins, rich in resources and cultural quality; some other ones considered “minor” but vital enough thanks to the new rural policy; and, at last, some other marginal areas

The Experience-Oriented Tourism in Tuscan Rural Areas

Despite the present scenario of general economic uncertainty, Tuscan rural spaces are still appealing to tourists from Italy and abroad. The changes which took place in the early 1990’s are still evolving in these rural places, where farmers are adapting their supply to the demand of this changing market. In fact, nowadays, there still is a tourist demand for an old-style holiday in rural spaces which is based on the attraction towards natural places and genuine food, while a demand for a more stunning lamorous-style holiday is increasing. The widespread presence of farms involved in tourism is sizable, with more than 4,000 farms (and about 52,000 beds) recorded in 2011, which were dispersed around places with valued cultural landscape and places with valued cultural landscape and linked to apreciated and certified products which in some areas are the pivotal resources. Rethinking rural tourism and agritourism through a wider range of integrated and customized services and looking at rural areas from a different perspective represent two important strategies in order to implement the experience-oriented tourism in the countryside too

Space-weighted seismic attenuation mapping of the aseismic source of Campi Flegrei 1983-84 unrest

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Decoherence of number states in phase-sensitive reservoirs

The non-unitary evolution of initial number states in general Gaussian environments is solved analytically. Decoherence in the channels is quantified by determining explicitly the purity of the state at any time. The influence of the squeezing of the bath on decoherence is discussed. The behavior of coherent superpositions of number states is addressed as well.Comment: 5 pages, 2 figures, minor changes, references adde

Can Fiscal Budget-Neutral Reforms Stimulate Growth? Model-Based Results

This paper focuses on growth enhancing budget-neutral fiscal reforms, i.e. changes in the composition of government revenues and spending that stimulate GDP growth while keeping the ratio of the fiscal budget to GDP constant. To this aim, we present simulation results using a multi-country DSGE model with three large economic regions, the US, the euro area and the rest of the world. The model features constrained and unconstrained non-Ricardian households and a detailed government sector; its multi-country nature allows investigating cross-country spillovers. The paper focuses on the most growth-friendly budget-neutral fiscal measures: (i) an incomplete fiscal devaluation (ii) a rise in government investment compensated by a fall in government consumption and (iii) a rise in government investment compensated by a rise in consumption and labor taxes. Dampening or amplifying effects due to coordination across policies (monetary and fiscal) and across economic regions are also considered. Three main results stand out. First, an increase in government investment financed by rising less distortionary taxes appears to be an effective growth-friendly budget-neutral reform in the sense that it generates both short- and long-run GDP growth and improves fiscal sustainability. Second, benefits and costs of budget-neutral reforms are not equally distributed across agents, giving rise to a policy trade-off between growth and distributional consequences. Third, budget-neutral reforms do not have large cross-border trade spillovers; however, reforms coordinated across all countries in periods of accommodative monetary policy do have amplified domestic effects