Building flat space-time from information exchange between quantum fluctuations

We consider a hypothesis in which classical space-time emerges from information exchange (interactions) between quantum fluctuations in the gravity theory. In this picture, a line element would arise as a statistical average of how frequently particles interact, through an individual rate $dt\sim 1/f_t$ and spatially interconnecting rates $dl\sim c/f$. The question is if space-time can be modelled consistently in this way. The ansatz would be opposite to the standard treatment of space-time as insensitive to altered physics at event horizons (disrupted propagation of information) but by extension relate to the connection of space-time to entanglement (interactions) through the gauge/gravity duality. We make a first, rough analysis of the implications this type of quantization would have on the classical structure of flat space-time, and of what would be required of the interactions. Seeing no obvious reason for why the origin would be unrealistic, we comment on expected effects in the presence of curvature.Comment: 22 pages. v3: extended introductio

Cultural accessible pedestrian ways. The case of Faro historic centre

In a historic city the existence of accessible pedestrian routes constitutes an essential feature to a true access to culture heritage, contributing for processes of social inclusion. It is necessary to create accessible pedestrian infrastructures network to hold a set of attributes that guarantee usability for all citizens. The creation and design of an accessible physical environment should be considered as a criterion of urban quality, which will make walking more pleasant not only for the elderly and people with disabilities but, also, for the entire resident population and tourists. In this case study it is ascertainable whether the physical characteristics of pedestrian infrastructures of cultural interest, located in the Historical Centre of Faro (Portugal), comply with the requirements of the National Law of Accessibility. There has, therefore, been created a methodology for evaluating the accessibility of pedestrian infrastructure through the construction of performance indicators. The analysis is achieved through a model of evaluation of the degree of conformity of the spaces, and presented, spatially, with appeal to a Geographical Information System, which is a tool to support the decision taking in the processes of urban rehabilitation, thus contributing to the choice of priority areas of intervention in the field of accessibility. The diagnosis confirms the existence of inaccessible pedestrian infrastructure and concludes the need to trigger processes of urban renovation.info:eu-repo/semantics/publishedVersio

Emergent behaviors in the Internet of things: The ultimate ultra-large-scale system

To reach its potential, the Internet of Things (IoT) must break down the silos that limit applications' interoperability and hinder their manageability. Doing so leads to the building of ultra-large-scale systems (ULSS) in several areas, including autonomous vehicles, smart cities, and smart grids. The scope of ULSS is both large and complex. Thus, the authors propose Hierarchical Emergent Behaviors (HEB), a paradigm that builds on the concepts of emergent behavior and hierarchical organization. Rather than explicitly programming all possible decisions in the vast space of ULSS scenarios, HEB relies on the emergent behaviors induced by local rules at each level of the hierarchy. The authors discuss the modifications to classical IoT architectures required by HEB, as well as the new challenges. They also illustrate the HEB concepts in reference to autonomous vehicles. This use case paves the way to the discussion of new lines of research.Damian Roca work was supported by a Doctoral Scholarship provided by Fundación La Caixa. This work has been supported by the Spanish Government (Severo Ochoa grants SEV2015-0493) and by the Spanish Ministry of Science and Innovation (contracts TIN2015-65316-P).Peer ReviewedPostprint (author's final draft

Dynamics of polymers: classic results and recent developments

In this chapter we review concepts and theories of polymer dynamics. We think of it as an introduction to the topic for scientists specializing in other subfields of statistical mechanics and condensed matter theory, so, for the readers reference, we start with a short review of the equilibrium static properties of polymer systems. Most attention is paid to the dynamics of unentangled polymer systems, where apart from classical Rouse and Zimm models we review some recent scaling and analytical generalizations. The dynamics of systems with entanglements is also briefly reviewed. Special attention is paid to the discussion of comparatively weakly understood topological states of polymer systems and possible approaches to the description of their dynamics

Spatial networks with wireless applications

Many networks have nodes located in physical space, with links more common between closely spaced pairs of nodes. For example, the nodes could be wireless devices and links communication channels in a wireless mesh network. We describe recent work involving such networks, considering effects due to the geometry (convex,non-convex, and fractal), node distribution, distance-dependent link probability, mobility, directivity and interference.Comment: Review article- an amended version with a new title from the origina