Replica Symmetry Breaking in Cold Atoms and Spin Glasses

We consider a system composed by N atoms trapped within a multimode cavity, whose theoretical description is captured by a disordered multimode Dicke model. We show that in the resonant, zero field limit the system exactly realizes the Sherrington-Kirkpatrick model. Upon a redefinition of the temperature, the same dynamics is realized in the dispersive, strong field limit. This regime also gives access to spin-glass observables which can be used to detect Replica Symmetry Breaking.Comment: 6 pages, 3 figure

On the Topology of the Inflaton Field in Minimal Supergravity Models

We consider global issues in minimal supergravity models where a single field inflaton potential emerges. In a particular case we reproduce the Starobinsky model and its description dual to a certain formulation of R+R^2 supergravity. For definiteness we confine our analysis to spaces at constant curvature, either vanishing or negative. Five distinct models arise, two flat models with respectively a quadratic and a quartic potential and three based on the SU(1,1)/U(1) space where its distinct isometries, elliptic, hyperbolic and parabolic are gauged. Fayet-Iliopoulos terms are introduced in a geometric way and they turn out to be a crucial ingredient in order to describe the de Sitter inflationary phase of the Starobinsky model.Comment: 31 pages, LaTex, 7 eps figures, 2 table

Current quantization and fractal hierarchy in a driven repulsive lattice gas

Driven lattice gases are widely regarded as the paradigm of collective phenomena out of equilibrium. While such models are usually studied with nearest-neighbor interactions, many empirical driven systems are dominated by slowly decaying interactions such as dipole-dipole and Van der Waals forces. Motivated by this gap, we study the non-equilibrium stationary state of a driven lattice gas with slow-decayed repulsive interactions at zero temperature. By numerical and analytical calculations of the particle current as a function of the density and of the driving field, we identify (i) an abrupt breakdown transition between insulating and conducting states, (ii) current quantization into discrete phases where a finite current flows with infinite differential resistivity, and (iii) a fractal hierarchy of excitations, related to the Farey sequences of number theory. We argue that the origin of these effects is the competition between scales, which also causes the counterintuitive phenomenon that crystalline states can melt by increasing the density

Meandering evolution and width variation, a physics-statistical based modeling approach

Many models have been proposed to simulate and understand the long-term evolution of meandering rivers. These models analyze the hydraulics of the in-channel flow and the river bank movement (erosion \u2013 accretion) process in different ways, but some gap still remain, e.g. the stability of long-term simulations when width variations are accounted for. Here we proposed a physics-statistical based approach to simulate the river bank evolution, that erosion and deposition processes act independently, with a specific shear stress threshold for each of them. In addition, we link the width evolution with a parametric probability distribution (PPD) based on a mean characteristic channel width. We are thus able to obtaining stable long-term simulations with realistic and reasonable spatio-temporal distribution of the along channel width

Non-technological barriers to the diffusion of energy-efficient HVAC&R solutions in the food retail sector

SuperSmart is an European Union (EU) project aiming at speeding up the uptake of energy-efficient re- frigeration, heating and cooling solutions for Europe\u2019s food retail sector, reducing its energy use, lowering its environmental footprint and increasing its economic benefits. The project pursues the removal of non- technological barriers to efficient heating & cooling in the European food retail sector and supports the introduction of a new EU Ecolabel for food retail stores. Non-technological barriers have been mapped and categorized by preliminary interviewing food re- tail sector stakeholders. While highlighting a general positive attitude towards energy efficiency of the sector stakeholders, the results of the survey reveal the need for specific actions focused on improving the knowledge level of technical staff, from the planning and design stage down to servicing and main- tenance. Raising awareness about available technology and financial support is also required. In general terms, barriers are always perceived as stronger when moving North to South, and West to East in Europe, thus emphasizing the need for homogenization of virtuous practices and attitudes throughout Europ

Real estate market and building energy performance: Data for a mass appraisal approach

Mass appraisal is widely considered an advanced frontier in the real estate valuation field. Performing mass appraisal entails the need to get access to base information conveyed by a large amount of transactions, such as prices and property features. Due to the lack of transparency of many Italian real estate market segments, our survey has been addressed to gather data from residential property advertisements. The dataset specifically focuses on property offer prices and dwelling energy efficiency. The latter refers to the label expressed and exhibited by the energy performance certificate. Moreover, data are georeferenced with the highest possible accuracy: at the neighborhood level for a 76.8% of cases, at street or building number level for the remaining 232%. Data are related to the analysis performed in Bonifaci and Copiello [1] about the relationship between house prices and building energy performance, that is to say, the willingness to pay in order to benefit from more efficient dwellings

A novel on-board Unit to accelerate the penetration of ITS services

In-vehicle connectivity has experienced a big expansion in recent years. Car manufacturers have mainly proposed OBU-based solutions, but these solutions do not take full advantage of the opportunities of inter-vehicle peer-to-peer communications. In this paper we introduce GRCBox, a novel architecture that allows OEM user-devices to directly communicate when located in neighboring vehicles. In this paper we also describe EYES, an application we developed to illustrate the type of novel applications that can be implemented on top of the GRCBox. EYES is an ITS overtaking assistance system that provides the driver with real-time video fed from the vehicle located in front. Finally, we evaluated the GRCbox and the EYES application and showed that, for device-to-device communication, the performance of the GRCBox architecture is comparable to an infrastructure network, introducing a negligible impact

Messiah: An ITS drive safety application

This article describes a novel safety application based on the open source navigation software OsmAnd, which runs on the Android platform. The application offers vehicles with "smart navigation", and maintains a network of the vehicles that use our application. The process of network creation and maintenance is important as our application enables vehicles to communicate with one another to exchange useful information. The main function of the application is to inform vehicles of relevant vehicles approaching, termed as "administrative vehicles" in this article, and include ambulances, police cars and fire brigades. Based on the received information, our application notifies the driver, who can now take navigation decisions based on it. While developing the application, problems were found when attempting to create an Ad-hoc network. A solution to the problem of managing the Ad-hoc network has been proposed and is under development